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User's Guide for the Draft Overhaul AERMOD
Meteorological Preprocessor (AERMET)
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EPA-454/D-21-001
December 2021
User's Guide for the Draft Overhaul AERMOD Meteorological Preprocessor (AERMET)
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Air Quality Assessment Division
Research Triangle Park, North Carolina
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Disclaimer
This report has been reviewed by the Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, and has been approved for publication. Mention of trade
names or commercial products does not constitute endorsement or recommendation for use. The
following trademarks appear in this guide:
Microsoft is a registered trademark of Microsoft Corp
IBM is a registered trademark of International Business Machines
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Preface
AERMET provides a general-purpose meteorological preprocessor for organizing
available meteorological data into a format suitable for use by the AERMOD air quality
dispersion model. This user's guide provides instructions for setting up and running the draft
overhauled version (21DRF) of the AERMET preprocess for which the Fortran source code has
been rewritten to take advantage of features included in more recent versions of the Fortran
coding standards. Note, this draft version of AERMET is being released for public review,
comment, and testing. This version is not a replacement of the current regulatory version
(21112) and should not be used for regulatory modeling applications
Hourly surface observations from the National Weather Service (WVS). Federal
Aviation Administration (FAA) or other sources. NW S twice-daily upper air soundings, data
from a site-specific meteorological measurement program, and data from prognostic
meteorological models can be processed in AI-RMI-T This draft version includes two stages for
processing the data The first stage extracts meteorological data from archive data files and
processes the data through \ arious quality assessment checks The second stage reads the
processed meteorological data from stage I and estimates the necessary boundary layer
parameters lor use In AI-RMOI). AI-RMI-T generates two meteorological output files for input
to AERMOI) a file of hourly boundary layer parameter estimates and a file of multiple-level
obsen ations of wind speed and direction, temperature, and standard deviation of the fluctuating
components of the wind
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Acknowledgments
The AERMET User's Guide was originally prepared by James O. Paumier and Roger W.
Brode of MACTEC, Research Triangle Park, North Carolina. This effort was funded by the
U.S. Environmental Protection Agency under Contract No. 68D70069, with Warren D. Peters as
Work Assignment Manager.
The Agency wishes to acknowledge AERMIC (the American Meteorological
Society/Environmental Protection Agency Regulatory Model lmpro\ ement Committee),
members of which have given a considerable amount of time, energy, and dedication over the
last 10 years to develop the AERMOD air dispersion modeling system
J. C. Weil, Cooperative Institute for Research in I ji\ ironmenlal Sciences, University of
Colorado
A. Venkatram, College of I jigineering. I ni\eisily of California at Riverside
R. B. Wilson, U.S. I\n\ironmenlal Protection Agency. Region X
R. J. Paine. IASR Corporation
S.G. Perry1. Atmospheric Sciences Modeling l)i\ision, Air Resources Laboratory, EPA/NOAA
R. F. Lee. Consultant, Meteorologist
A. J. Cimorelli. I S Environmental Protection Agency, Region III
W.D. Peters, U.S. I-n\ ironmenlal Protection Agency, OAQPS, EMAD, AQMG
1 On assignment to the Atmospheric Research and Exposure Assessment Laboratory, U.S.
Environmental Protection Agency.
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Contents
1.0 Introduction 1-1
1.1 Overview of AERMET 1-1
1.1.1 Stage 1 - extraction and quality assessment 1-4
1.1.2 Stage 2- PBL calculations and create model input files 1-6
1.2 Output files 1-7
1.3 Document Overview 1-7
1.4 Differences with older versions of AERMI-T 1-8
1.4.1 Control file differences 1-8
1.4.2 Other differences 1-9
2.0 Running AERMET 2-1
2.1 AERMET execution 2-1
2.2 Control file 2-2
2.2.1 Control file setup 2-3
3.0 Keyword reference ... 3-1
3 I Definitions and control 11 le processing 3-1
3 2 JOU Pathway 3-2
3 : I MUSS AC lis 3-2
3 : : Rl-PORT 3-2
3.2.3 CI IK SYYI'.W 3-3
3.2.4 NOPRIXT 3-4
3.2.5 DEBUG 3-4
3.3 SURFACE pathway 3-5
3.3.1 DATA 3-6
3.3.1.1 CD-144 and SCRAM formats 3-7
3.3.1.2 SAMSON format 3-9
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3.3.2 EXTRACT 3-10
3.3.3 XDATES 3-10
3.3.4 LOCATION 3-12
3.3.5 QAOUT 3-13
3.3.6 AUDIT 3-15
3.3.7 RANGE 3-16
3.3.8 NO MISSING 3-17
3.4 UPPERAIR 3-18
3.4.1 DATA 3-18
3.4.2 EXTRACT 3-20
3.4.3 XDATES 3-20
3.4.4 LOCATION 3-22
3.4.5 QAOIT 3-23
3.4.6 Al 1)11 3-25
3.4.7 RANGi: 3-25
3 4 S NO MISSING ... 3-26
3 4 ^ MODII Y 3-27
3.5 ON SHE or PROG . 3-28
3.5 I DATA 3-29
3.5.2 EXTRACT 3-30
3.5.3 READ and FORMAT 3-30
3.5.4 XDATES 3-36
3.5.5 LOCATION 3-37
3.5.6 QAOUT 3-38
3.5.7 AUDIT 3-40
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3.5.8 RANGE 3-41
3.5.9 NO MISSING 3-42
3.5.10 OSHEIGHTS 3-42
3.5.11 DELTATEMP 3-43
3.5.12 THRESHOLD 3-44
3.5.13 OBS/HOUR 3-45
3.6 MERGE 3-46
3 .7 METPREP 3-46
3.7.1 DATA 3-46
3.7.2 MODEL 3-47
3.7.3 A SOS 1VI IN 3-47
3.7.4 I IIRI1SII 1VIIN 3-49
3.7.5 LOCATION 3-50
3.7.6 NWS I Ki l 3-52
3.7.7 XI)ATi:s 3-52
3 7S Mi l l l()l) ... 3-54
3 7 WIND l)IK . .. 3-55
3 7 10 KI1I1J A I 1 3-56
3.7 I I ASOS AD.I 3-56
3.7.12 sr.\m.i:m 3-57
3.7.12.1 BULKRN 3-57
3.7.12.2 ADJU* 3-58
3.7.13 CCVR and TEMP 3-59
3.7.14 SUNRISE 3-60
3.7.15 UAWINDOW 3-63
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3.7.16 Surface characteristics 3-64
3.7.16.1 Frequency and number of sectors: FREQSECT or FREQSECT2... 3-65
3.7.16.2 Defining sectors: SECTOR or SECTOR2 3-67
3.7.16.3 Specification of surface characteristics: SITE CHAR or
SITE CIIAR2 3-68
3.7.16.4 Optional keywords AERSURF and AI-RSI RI 2 3-72
3.7.16.5 Optional yearly assignment of surface characteristics 3-73
3.8 Output from Stage 2: OUTPUT and PROI II I ¦ 3-76
4.0 Example AERMET runs 4-1
4.1 National Weather Service data 4-1
4.1.1 Surface data extraction 4-1
4.1 2 Upper air data 4-11
4.1 3 Data merger and boundary layer calculations 4-22
4.2 Site-specific example 4-32
4.2 I Site-specific data extraction 4-32
4.2 2 Data merge and boundary layer calculations 4-42
5 i) Technical Notes 5-1
5 I (Quality assessment procedures 5-1
5.2 Identifying ASOS observations 5-3
5.3 Validation of MVS surface format by active data range 5-4
5.3.1 Validation of WBAN between Stage 1 control file and NWS surface data file5-
5
5.3.2 ASOS cloud cover from SCRAM and SAMSON set to missing 5-6
5.4 Site-specific data - averaging sub-hourly values 5-6
5.5 Station elevations 5-7
5.6 Boundary layer parameter estimates 5-10
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5.6.1 Reference wind and temperature 5-10
5.6.2 Surface characteristics 5-11
5.6.2.1 Choice of sector-dependent surface characteristics 5-12
6.0 References 6-1
Appendix A. Functional keyword/parameter reference A-l
Appendix B. Variable names and default OA values B-l
Appendix C. Data File Formats C-l
C. 1. EXTRACT/QAOl T files C-l
C. 2. OUTPUT and I'ROI II .K outputs C-5
Appendix D. Messages D-l
D. 1. Error inessages D-2
D. 2. Warning messages D-5
D. 3 Tnformalional messages D-8
D. 4 Oualilx assurance messages.. D-10
Appendix E AI-RVTF.T modules and subroutines E-l
Appendix l;. Com pari son of 21DRF AERMET to 21112 AERMET F-l
I ' I Meteorological data differences F-3
I' 2 AI-RMOI) e\aluations F-9
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Figures
Figure 1-1. AERMET processing steps 1-3
Figure 3-1. Time Zone Boundaries (with preferred sounding time across top) 3-62
Figure 3-2. Preferred sounding time by time zone 3-62
Figure 4-1. Control file to extract and QA NWS surface data 4-2
Figure 4-2. Processing steps for NWS surface data extraction 4-3
Figure 4-3. Contents of the SURFACE extraction message file 4-6
Figure 4-4. Input summary contents of the SI RI'ACI- extraction report file 4-7
Figure 4-5. QA summary contents of the SX RI'ACI- extraction report file 4-8
Figure 4-6. Message summary contents of the SURFACE extraction report file 4-9
Figure 4-7. Format of the SURFACE EXTRACT and QAOLT liles 4-10
Figure 4-8. Control file to extract and QA NWS upper air data 4-11
Figure 4-9. Processing steps for MVS upper air data extraction 4-12
Figure 4-10. Contents of the I 'PPI-RATR extraction message file 4-15
Figure 4-11. Input summary contents of the I PPERAIR extraction report file 4-16
Figure 4-12. Initial OA summary contents of the UPPLRA1R extraction report file. ..4-17
Figure 4-13. OA summary contents of the I PIM-RA1R extraction report file 4-18
Figure 4-14 I'inal OA summay contents of the IFPPERAIR extraction report file 4-19
I 'iuure 4-1 5 M essaue summary contents of the IJPPERAIR extraction report file 4-19
I 'iuure 4-16 l-orm.it of the I'PPERAIR i:\TRACTfile 4-20
I 'iuure 4-17. Format of the I 'I'PI-RAIR QAOUT file 4-21
Figure 4-1S Control file lor boundary layer calculations in METPREP 4-22
Figure 4-1 ^ IVocessi nu steps for boundary layer calculations 4-24
Figure 4-20. Initial contents of the stage 2 message file 4-25
Figure 4-21. Final contents of the stage 2 message file 4-26
Figure 4-22. Input summary contents of the stage 2 report file 4-28
Figure 4-23. METPREP summary contents of the stage 2 report file 4-29
Figure 4-24. Message summary contents of the stage 2 report file 4-30
Figure 4-25. Partial contents of the EX01_NWS.SFC file 4-31
Figure 4-26. Partial contents of the EX01_NWS.PFL file 4-32
Figure 4-27. Partial contents of the site-specific data file ONSITE.MET 4-33
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Figure 4-28. Control file to extract and QA site-specific data 4-34
Figure 4-29. Control file to extract and QA site-specific data 4-35
Figure 4-30. Contents of the ONSITE_Sl_MESSAGE.TXT message file 4-36
Figure 4-31. Input summary contents of the ONSITE extraction report file 4-38
Figure 4-32. QA summary contents of the ONSITE extraction report file 4-39
Figure 4-33. Message summary contents of the ONSITE extraction report file 4-40
Figure 4-34. Partial contents of the ONSITE QAOFT file 4-41
Figure 4-35. Control file for boundary layer calculations in METPREP 4-44
Figure 4-36. Processing steps for the boundary layer calculations 4-45
Figure 4-37. Initial contents of the slaue 2 message file ONSITF. S2_MESSAGE.TXT 4-
46
Figure 4-38. Partial contents of the stage 2 message file
ONSITE S2 MESSAGE.TXT 4-47
Figure 4-39.
48
Figure 4-40.
Figure 4-41.
Figure 4-42
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I 'iuiii e 4-43
I 'iuiii e 4-44.
Figure 4-45
Final contents of the stage 2 message 11 le ONSITE S2_MESSAGE.TXT. 4-
Tnpiit summary contents of ONSITI! S2 RI!PORT TXT 4-50
Ml: IPRI P summary contents of ONSITI-! S2 RI!l>ORT.TXT 4-51
Surface characteristics summary contents of ONSITE_S2_REPORT.TXT 4-
Message summary contents of ONSITE_S2_REPORT.TXT 4-53
Partial contents ofONSITI! NWS.SIC 4-54
Partial contents of ONSITE NWS.PFL 4-55
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Tables
Table 3-1. Albedo of Ground Covers by Land Use and Season 3-69
Table 3-2. Daytime Bowen Ratio by Land Use and Season - Dry Conditions 3-70
Table 3-3. Daytime Bowen Ration by Land Use and Season - Average Moisture Conditions. 3-70
Table 3-4. Daytime Bowen Ratio by Land Use and Season - Wet Conditions 3-71
Table 3-5. Surface Roughness Length, in Meters, by Land Use and Season 3-71
Table 5-1. Format Active Dates 5-5
Table A-l. Description of Job Pathway Keywords A-3
Table A-2. Description of Keyword Parameters for l Ik- JOIJ Pathway A-4
Table A-3. Description of SURFACE Pathway'keywords A-5
Table A-4. Description of Keyword Parameters lor the SURF ACL Palhw ay A-6
Table A-5. Description of UPPERAIR Keywords A-10
Table A-6. Description of Keyword Parameters for the I 'PPIiR.UR Pathway A-l 1
Table A-7. Description of ONSITI- PROG Pathway keywords A-15
Table A-8. Description of Keyword Parameters for the OlSSITI- PROG Pathway A-17
Table A-9. Description of MI-TPRI-P Pathway keywords A-22
Table A-10. Description of keyword Parameters for the METPREP Pathway A-25
Table B-l. Variable and OA Defaults for SI RFACE Variables B-3
Table B-2 Variable and OA Defaults for I PPI-RALR Variables B-5
Table B-3 Variable and OA Defaults for ONSITE or PROG Single Level and Date/Time
Variables .. B-6
Table B-4 Variable and OA Defaults for ONSITE or PROG Multi-level Variables B-8
Table C-l. SURI-'ACI- I-XTRACT and QAOUT file header format and data format C-2
Table C-2. UPPI-RAIR l-XTRACT and QAOUT file header format and data format C-3
Table C-3. ONSITE/PROG l-XTRACT and QAOUT file header format and data format C-4
Table C-4. OUTPUT file format C-6
Table C-5. PROFILE file format C-8
Table E-l. List of subroutines and functions in module MAIN1 E-l
Table E-2. Subroutines and functions in module MISC E-3
Table E-3. Subroutines and functions in module ONSITE E-4
Table E-4. Subroutines and functions in module PBL E-6
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Table E-5. Subroutines and functions in module SURFACE E-8
Table E-6. Subroutines and functions in module READINPUT E-10
Table E-7. Subroutines and functions in module REPORTS E-10
Table E-8. Subroutines and functions in module UPPERAIR E-l 1
Table F-l. AERMOD evaluation databases F-2
Table F-2. Meteorological variables for comparison with tolerances F-3
Table F-3. Observed and modeled robust highest concentrations for databases not subject to the
EPA protocol for determining best performing model F-l 1
Table F-4. Composite Performance Measure (CPM) lor databases subject to the EPA protocol
for determining best performing model F-12
Table F-5. Model Comparison Measure (MCM). standard error (SI-) and MCM/SE ratios for
databases subject to the EPA protocol for determining best performing model F-12
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1.0 Introduction
The U. S. Environmental Protection Agency (EPA), in conjunction with the American
Meteorological Society (AMS), developed the AMS/EPA Regulatory Model (AERMOD),
promulgated by the EPA in 2005 as the preferred regulatory air dispersion model for predicting
near-surface pollutant concentrations within 50 kilometers (km) of an emission source.
AERMET, the subject of this user's guide, is the meteorological preprocessor for AERMOD
and estimates the atmospheric boundary layer (BL), also called the planetary boundary layer
(PBL), parameters used in the dispersion calculations in AERMOD
The version of AERMET discussed in this user's guide, version 21 l)RF, is a draft
version of AERMET that represents a complete o\ eihaul of the computer code of AERMET.
The source code for AERMET was rewritten from AI-RMI-!T \ersion 19191 and 21112 and
reflects updated Fortran coding practices Differences between AERMET 21112 and 21DRF
are discussed below in Section 1 4 At this time, the draft \ersion of AERMET is for testing
purposes only and should not he used for regulatory applications involving AERMET.
AERMET 21112 should he used lor regulatory applications at this time.
1.1 Overview of AKU.MKT
AI-RMI-T processes four types of data: 1) hourly surface observations that are typically,
but not e\clusi\ ely. collected at airports by the National Weather Service (NWS) and/or the
Federal Aviation Administration (IAA); 2) twice-daily upper air soundings collected by the
NWS; 3) data collected from an on-site or site-specific measurement program; and 4) prognostic
meteorological data processed through a processor such as the Mesoscale Model Interface
(MMIF) (EPA, 2018; Ramboll, 2021)2. Data processing occurs in two distinct stages that are
unrelated to the type of data being processed. These stages can be run separately or together in
2 Throughout this document, site-specific references will also apply to the processing of MMIF output,
which is processed in the PROG pathway in AERMET and uses the same processing as ONSITE data.
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one AERMET run; the stages are illustrated in
Figure 1-1. The first stage extracts the surface and upper air data from files in which the
data are stored in specific archive formats. The quality of the surface, upper air, and site-
specific or prognostic data is also assessed during Stage 1. The second stage reads the output
from stage 1, calculates the boundary layer parameters required by AERMOD, and generates
two AERMOD-ready meteorological data files.
Note in
Figure 1-1 that the extraction phase of the raw site-specific data or processed prognostic
data is not included in Stage 1, though the data are QA'd in Stage 1. Unlike the surface and
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upper air data, site-specific and processed prognostic data are not stored (archived) in any
particular format. Therefore, the data are not "extracted" from an archive file and only need to
be QA'd. This is explained in more detail in Section 3.5. Another important point to mention
with respect to Figure 1-1 is the input of 1-minute Automated Surface Observing Systems
(ASOS) data into Stage 2, referred to in the figure as 'Hourly averaged 1-minute ASOS winds.'
1-minute ASOS data are surface wind data collected by the NWS/FAA with ASOS, stored as 1-
minute averages, and archived separately from the hourly NWS/FAA surface data. These
higher resolution wind data can be processed separately with the AERMINUTE program (EPA,
2015) to produce 1-hour averages that are more representative than the surface wind data in the
standard hourly archive formats (see Section 3.3). For more recent years (the year 2000 and
later), the hourly wind data in the standard archive formats can be replaced with the hourly
values derived from AERMINUTE output when those data are available. Refer to Section 3.7.3
for a detailed discussion on the use of 1-minute ASOS wind data. From here on, this user's
guide refers to all surface data collected by the NWS and/or the FAA, including the 1-minute
ASOS data, as NWS data. Surface characteristics are also input to Stage 2 and can be calculated
from processors such as AERSURFACE (EPA, 2020) for observed data and from the prognostic
model when processing prognostic data.
Figure 1-1. AERMET processing steps
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The AERMET program is designed to read a plain text file (a.k.a., the control file) which
contains the processing instructions such as user-specified options and the names and locations
of the input and output data files. Prior to version 18081 of AERMET, the control filename was
hardcoded as 'AERMET.INP'. Beginning with version 18081, the user can specify the control
filename on the command line when running AERMET. The input file can be in a different
directory than the directory in which the user is working, and the full pathname or relative
pathname can be entered. If no input file is provided, the hardcoded default 'AERMET.INP' is
assumed and must be in the directory in which the user i s u orki ng Note that all AERMET
output filenames are user-specified, which is created automatically by AERMET during
processing.
Prior to version 21DRF, AERMET was configured to be run in three stages (extraction
and QA, data merger, and PBL calculations) with each stage run separately. Ik'uinning with
21DRF, AERMET has been configured that only two stages are executed (extraction and QA
and PBL calculations) and both stages can he executed in the same AERMET run. It is no
longer necessary to run each stage separately¦. and the data merger stage has been eliminated.
Therefore, existing AI-R\II-!T control files must he re\ ised More details on the differences
between the 21DRF \ ersion and earlier \ ersions can he found in Section 1.4.
In a typical application AI-RMI-T can he executed two ways: 1) two times, once for
stage I processing (extraction and quality assurance (OA) of the surface, upper air, and site-
specific data or prognostic data combined in a single run) and a second time for stage 2
processing (boundary layer calculations and output); 2) alternatively AERMET can be executed
once, running both stage 1 and 2 in the same AERMET run (see Section 1.4.1 for information
on combined stage control files). Since stage 1 processing is designed to support QA of raw
input data, stage 1 may in\ ol\ e multiple iterations if data problems are encountered. Prior to
running AERMET, the user should review the instructions in the control file and, as necessary,
replace them with instructions appropriate to the specific application and stage of processing. If
running each stage separately, a separate control file would be required for each stage and each
given a unique name to avoid conflicts when the files are stored in the same directory.
1.1.1 Stage 1 - extraction and quality assessment
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Stage 1 comprises the extraction/retrieval of data and assessment of the quality of the
data. Data extraction is generally a one-time activity, while the quality assessment (QA) may be
performed several times if the QA identifies problems with the data.
In the past, the NWS upper air and surface data are available from the National Oceanic
and Atmospheric Administration (NOAA) in a compact format. These formats are designed to
minimize the amount of space required to store the data and are not readily interpreted.
Therefore, the data that are stored in archive files are first extracted (i.e., retrieved) from the
archive file.
AERMET can extract upper air sounding data from three formats including: TD-6201,
the former Forecast Systems Laboratory (FSI.) format, and beginning with 21 DRF, the
Integrated Global Radiosonde Archive (IGRA). While TI)-(->2<)| is no longer in use, global
upper air data in FSL format is available online from the NOAA Larth System Research
Laboratory (ESRL) Radiosonde Database at m tbs/ and the IGRA format is
available from the NOAA National Centers lor I-n\ ironmental Information (NCEI) at
ftp: //ftp. n cei. n oaa. /r"1h/A
AERMET can extract surface hourly weather observations from several standard formats
thatha\e been used by NOAA's National ( enters for 1'iivironmental Information (NCEI)
including Card Deck 144 (CD-144). Solar And Meteorological Surface Observation Network
(SAMSON). I lonrly Surface Weather Observations (HUSWO), and the Integrated Surface
Hourly Database (ISHD a.k.a ISI I, 1SD and DSI-3505), which are time-based formats (i.e., by
hour). Prior to \ ersion 21DRI-. Al vRMET could also process the TD-3280 format, which is
element-based (i.e., by variable), originally stored on magnetic tape. Beginning with version
21DRF, AERMET no longer supports the TD-3280 format due to its age. While data stored in
some of the older formats (CD-144, SAMSON, and HUSWO) may be part of users' personal
archives and some formats may be available for purchase from the NCEI, recent U.S. and global
data are available for download via File Transfer Protocol (FTP) free of charge from the NCEI
at: https://wwwl.ncdc.noaa.eov/piib/data/noaa (web browser) or
ftp://ftp.ncei.noaa.gov/pub/data/noaa (ftp client, anonymous access).
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AERMET also processes an hourly surface data format available from the EPA Office of
Air Quality Planning and Standards (OAQPS). This format is a reduced form (fewer variables)
of the CD-144 format and is available for 1984-1992 from the Support Center for Regulatory
Air Models (SCRAM) website (https://www.epa.gov/scram).
There is no standard format or content for site-specific or processed prognostic
meteorological data. These data most likely will include ohser\ at ions made at one or more
levels on an instrumented tower or from remote sensing instrumentation or modeled vertical
grid for prognostic data. Additionally, near-surface measurements such as insolation, net
radiation, and temperature difference may be included. The non-stand a idi/ed formats preclude
storing these data in a predefined archive formal: lluis, AERMET does nol 'extract' site-specific
data. However, AERMET can read site-specific or processed prognostic data stored in an
ASCII3 file with a structure that can he described by the user with standard Fortran format
statements. Additional restrictions and specification of site-specific and prognostic data are
discussed in more detail in Section 3 53 5
Quality assessment (OA) is performed on all the data types except the 1-minute ASOS
wind data. The QA process identi lies occurrences of missing data, values that are outside a
range of \ allies, and inconsistences between selected variables within an observation period.
Default \ allies are defined lor the upper and low/er bounds and for missing values. The values
can be modified through the control file created by the user. Some variables are checked by
default (as noted in the tables in Appendix B) and the user can specify additional variables to be
checked.
If AERMET delects anomalous data, a message is written to a file informing the user of
the violation. At present there are no provisions for AERMET to automatically replace missing
data or correct "suspect" values. The user should review the QA messages and determine if the
value(s) require modification or if they are acceptable.
3 American Standard Code for Information Interchange
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If the data require modification, the output files from Stage 1 can be edited using a text
editor. However, any changes should be based on sound meteorological principles and comply
with any relevant regulatory guidance. Modifications should only be done on extracted data, and
not on the archive or raw data file. The archived or row data should never be altered but should
be maintained as delivered. Whenever changes are made, the modified data should be
reprocessed through the QA process a second time. This stepwise procedure may identify new
problems that, in turn, need to be addressed. When the user is satisfied that the quality of the
extracted data cannot be improved further, the data arc ready lor the next stage.
1.1.2 Stage 2- PBL calculations and create model inpm files
The second stage of processing reads the output generated in Stage I. computes the
boundary layer scaling parameters (e.g . surface friction \ elocity, mixing height, and Monin-
Obukhov length), and produces two input files for AI-RMOI) The first file contains the
computed boundary layer paramelers. as well as the observed surface parameters (e.g.,
temperature, wind speed, and wind direction) The second file contains one or more levels (a
profile) of winds, temperature, and the standard de\ iation of the lluctuating components of the
wind if provided. Site-specific monitoring programs commonly collect temperature and wind
measurements at multiple le\ els The prognostic data are also commonly multilevel as well.
These multile\ el data are w riling to profile file In the absence of multilevel site-specific data, a
single le\ el from site-specific or NW S hourly surface observations are written to this file.
1.2 Output llles
AERMET creates se\ eral llles during each stage of processing. These include a report
file that summarizes user options and QA results, a message file that stores errors, warnings, and
detailed QA messages generated during processing, separate extraction files for the NWS
surface and upper air data, and separate data quality assessment files for NWS surface, upper
air, and site-specific or prognostic data. The extraction files contain the data that are extracted
from archive formats during Stage 1 and subsequently QA'd. The assessment files contain the
QA'd data and are nearly identical in structure and content to the extraction files. The
assessment files are input to into Stage 2. As mentioned previously, site-specific (prognostic)
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data, processed via the ONSITE (PROG) pathway, are read and QA'd directly from the user-
supplied file.
The structure and contents of the summary and message files are discussed in the
examples discussed in Section 4.0. The structure and content of the extraction and assessment
files are provided in Appendix C. It is important that the user not alter any of the header records
in the assessment files since they are input into Stage 2. otherwise the data could be processed in
an undesirable way or cause AERMET to fail with a proccssi ng error.
1.3 Document Overview
Section 2.0 describes the running of AI-RMI-T Section 3.0 describes the keywords for
each pathway in detail and Section Error! Reference source not found, presents a basic
tutorial of AERMET. Section 0 presents technical notes about AliRMET. Appendix A through
Appendix D present more information about keywords ( Appendix A), meteorological variables
(Appendix B), file formats ( Appendix ('). and \arions messages (Appendix D). Appendix E
provides a summary of the different AI-RMI-T modules and subroutines, and Appendix F
summarizes AERMOI) e\alnations using AI-RMI-T 21DRF and 21112.
1.4 Differences with older versions of AKUMT'T
As part of the update process to AI-RMET, there are several differences between version
21DRF of AI-RMI-T and pre\ ions \ ersions (21 112 and earlier). This section describes some of
the changes, including control file changes, user options, and programming changes that will
result in differences betw een 21 l)RF AERMET and earlier versions (21112 and earlier).
1.4.1 Control file differences
As part of the update process to AERMET, changes were made to AERMET that will
require the user to modify existing AERMET control files. The first such change is that the
XDATES keyword for each path now requires the years to be entered as 4-digit years.
Previously AERMET allowed for 2-digit or 4-digit years. Use of 4-digit years makes
1-8
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processing for years spanning a century crossover i.e., 1999-2004, easier. See Sections 3.3.3,
3.4.3, 3.5.2, and 3.7.7 for further information for date extractions for SURFACE, UPPERAIR,
ONSITE or PROG, and METPREP processing.
As discussed in Section 1.1, beginning with version 21DRF, AERMET is now a two-
stage process, instead of a three-stage process. To facilitate the use of existing AERMET input
control files, AERMET 21DRF will read existing control files and ignore paths and keywords
that are no longer needed. To run an existing stage 1 control file, the only change that is needed
by the user is to make sure the years associated with XDATI-S are 4-digit years. To run stage 2
(old stage 3) by itself, the user can combine an existing stage 2 and stage 3 control file into one
control file and remove the old stage 3 JOB pathway and keywords. \l- RVfET will ignore the
older MERGE pathway and DATA keyword associated with the METPRI-P path Also, the user
should ensure all years associated with XDATES are 4-digit years. To run a new combined
stage 1 and 2 AERMET run, the user can combine existing stage 1, 2, and 3 control files into
one control file and as previously staled. AI-RMI-T will ignore the MERGE pathway and
DATA keyword associated with the MI-TI'RI-P path Again, the user should ensure all years
associated with XDATI-S are 4-digit years and remo\ e the stage 2 and stage 3 JOB pathway and
keywords.
1.4.2 Other differences
The foil owing is a list of differences between 21DRF AERMET and previous versions
of AERMI-T The list includes the topics discussed above in Section 1.4.1. For some
differences, the user can expect to see differences in output between 21DRF AERMET and
previous versions. Those expected differences are also explained when applicable.
AERMET is now a two-stage process instead of a three-stage process. The merge stage,
stage 2 in previous versions of AERMET has been eliminated and the previous Stage 3
is now Stage 2. If the MERGE pathway (Section 3.6) is found in the AERMET control
file, AERMET will ignore the associated keywords. Likewise, if AERMET encounters
the DATA keyword (Section 3.7.1) with the METPREP pathway (Section 3.7),
AERMET will ignore the DATA keyword and associated file (old Stage 2 output).
1-9
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Years associated with XDATES must be 4-digit years.
AERMET will now preserve the case (lower or upper case) of any input or output files,
instead of assuming all uppercase for filenames. This makes the code more portable for
Linux operating systems as Linux systems are case sensitive while Microsoft Windows
DOS systems are case insensitive.
Stage 1 EXTRACT and QAOUT files have different formats between AERMET 21DRF
and previous versions. The ONSITE QAOUT file now has a consistent format whereas
before the QAOUT file followed the formal of the raw input file.
A new averaging option for vector averaging of winds has been added to Stage 1 for
sub-hourly site-specific data. The user in\ okes the option by specilying the word
VECTOR after the number of obser\ alions per hour with the OBS HOUR keyword.
The default averaging is a scalar a\ erage
A new upper air data source, the Integrated Global Radiosonde Archive (IGRA), has
been added in addition to the (On I and I SI. formats
The ->2S() format for SI RI 'ACI- data has been dropped and will no longer be supported
by future \ ersions of AliRMI-T
Addition ofa new pathway, PROG for prognostic data. The PROG pathway is
analogous to the 0\SITI- pathway and uses the same keywords. The PROG pathway is
utilized for prognostic data to allow for processing of certain variables when the
application is overwaler versus overland (Section 3.5.1). When using the PROG
pathway, AERMET will output a text string to the AERMET OUTPUT file (Section 3.8)
in the header and for each hour denoting that the data are prognostic. This allows
AERMOD to know the data are prognostic.
In conjunction with the new PROG pathway, AERMET has additional ONSITE or
PROG variables that can be used for overwater applications. See Appendix B, Tables B-
1-10
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3 and B-4. See Section 3.5.1 for details on the overland or overwater assignments and
treatment of variables.
Also, in conjunction with the overland or overwater applications, if Monin-Obukhov
length is an input variable and used for overwater applications, AERMET will use
Monin-Obukhov length to determine the stability of the hour (convective or stable)
instead of the solar angle approach currently used The solar angle approach is used
when Monin-Obukhov length is not available.
AERMET now allows for the specification of year specific surface characteristics via the
FREQSECT, FREQ SECT2, AERSl IU. and AERSURF2 keywords. This allows for
a multi-year AERMET run for stage 2 in one AERMET run instead of separate annual
AERMET runs when surface characteristics change on an annual basis. See Section
3.7.16.5 for more details.
For seasonal surface characteristics only. .\I-R\II-T uses the primary and secondary
station coordinates to determine the hemisphere of the respective station. This is used to
allocate the seasonal characteristics to the appropriate months based on the hemisphere.
I or example. Ibr winter characteristics, if the station is in the northern hemisphere, the
winter characteristics are assigned to January. I'ebruary, and December. If the station is
in the southern hemisphere, then the winter characteristics are assigned to June-August.
This feature allows the user to enter seasonal characteristics that represent the season for
the hemisphere That is. for applications in the southern hemisphere, the user does not
need to assign representing e summer surface characteristics to winter so that AERMET
will assign the characteristics to the correct months. See Section 3.7.16 for more details.
The no persistence keyword, NOPERS, used for cloud cover and temperature
substitution for hours 23 and 24 in METPREP are now obsolete. These keywords were
present because previous versions of AERMET processed each day separately within the
program and previous versions could not read ahead to the next day to allow for hours
23 and 24 interpolation. Based on the recoding of AERMET, AERMET can now read
1-11
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the next day's observations so hours 23 and 24 can be interpolated in the same manner
as other hours in the day.
In previous versions of AERMET, when processing NWS data, if hour 24 was
completely missing from the stage 2 output, i.e., the hour was not in the raw data file in
stage 1, AERMET would copy hour 23 (if available) to hour 24 for the day. This is no
longer done in 21DRF AERMET so hour 24 may be missing in the final AERMET
output or temperature and cloud cover may be suhsli Uilecl from hour 23 of the same day
and hour 1 or 2 of the next day. This change could result in differences for hours 24, 1,
and 2 when comparing 21DRF AERJVII-T to pic\ ious -versions of AERMET.
Hourly precipitation values may differ between 21DRT7 AERMI-T and previous
versions. Previous versions of AERMET do not reset hourly precipitation to zero in
METPREP before reading the precipitation from the MI-RGED output. This can result
in precipitation values for hours that are missing in the MI-RGE output because previous
versions of AERMET do not reinitialize the precipitation, so the previous day's value of
precipitation is used lor an hour 211)RI¦" AhRMhT corrects this issue.
Tor applications in\ ol\ ing site-specific or prognostic mixing heights, AERMET 21DRF
smooths the mixing height based on the pre\ions hour's mixing height in similar fashion
as when AI-RMI-T calculates mechanical mixing heights. Previous versions of
AI-RMI-T did not smooth the mechanical mixing heights read from the site-specific or
prognostic data
As part of the overhaul of AERMET, the variables that are type real in FORTRAN are
now double precision in AERMET. Previous versions of AERMET treated these
variables as real. Due to the differences between double precision and real, some
variables may have slightly different values due to rounding, and other variables may
have more differences as logic code within AERMET may have different output, even
though the numbers used in the logic are slightly different. This could result in different
processing based on the logic, leading to different output values.
1-12
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NWS wind speeds associated with variable wind directions are not corrected for
truncation in Stage 2 as done in previous versions of AERMET
1-13
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2.0 Running AERMET
This section is designed to provide the user with a basic understanding of the
requirements to run AERMET. This section will explain the pathway and keyword approach
and associated syntax rules for processing meteorological data in AERMET.
2.1 AERMET execution
AERMET is a DOS-based program and is run IV0111 the command prompt on computers
running a version of Microsoft Windows. AERMET can also be compiled and executed on
Unix or Linux systems. On Windows systems, the syntax for running A I - RMET for a single
stage or combined stages is:
path-to-AERh II. I.1 .XE A ERA 11 ¦ T
path-to-AERMLl.l.XI'. AERMET input filename
On Linux or Unix systems, the syntax is
iKiih-i(>-.\i:i{\u:i.i:xi: aermet
paih-lo-MJ\.\ II. I .I'.XEIAERMET inputJilename
whuivpaili-to- I/.R.\ 11.1.1 .XE is the directory path to the AERMET executable file. The
first example is applicable to all \ ersions of AERMET and assumes the input filename is
'aermet.inp' for each stage and the file resides in the current working folder or directory. The
second example is applicable to versions of AERMET beginning with version 18081 in which
the user can specify the input filename, which can include a full directory pathname for the file.
When running AERMET with no input filename as an argument, each stage's input file should
be copied to a file named aermet.inp (case insensitive on DOS and case sensitive on Unix or
Linux systems). Examples following in the rest of this document are for the latest version of
AERMET.
2-1
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As AERMET runs, the progress is displayed on the screen, unless the option NOPRINT
(Section 3.2.4) is specified on the JOB pathway (Section 3.2). In addition to the output data
files, each run will produce a message file and report file if specified. Note: the filenames and
extensions are all user-defined, i.e., there are no default names or extensions.
A word of caution for this example and for all AERMET runs: all output files are opened
with the Fortran file OPEN specifier of STATUS = 'UNKNOWN" With this specifier, if the file
already exists, the contents will be overwritten without any opportunity to save it.
More details and examples about running AI-RMI-T arc a\ ailahle in Section 4.0.
2.2 Control file
Processing meteorological data with the AERMI-T preprocessor is divided into two
stages as shown in Figure 1-1. Each stage can lx- run separately or in a combined run. A file
containing a sequence of control statements is required to define the actions that AERMET is to
perform and how to perform them This file is referred to as the input control file. There can be
a separate control file for stage of processing or a control file that runs both stages in one run. The
user can enter the unique name of the control file on the command line when executing
AERMI-T from the command line as discussed in Section 2.1.
The statements in the control file are divided into six functional groups, or pathways:
JOB for specifying information pertaining to the entire run;
UPPER.\IR for extracting and QA'ing NWS upper air sounding data;
SURFACE for extracting and QA'ing NWS hourly surface observations;
ONSITE for QA'ing user-supplied, site-specific meteorological data;
PROG for QA'ing user-supplied, prognostic meteorological data; and
METPREP for estimating boundary layer parameters for AERMOD.
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The pathway identifier appears on a line by itself and identifies the beginning of a
contiguous block of statements that apply only to that pathway. Depending on the stage of
processing and the type of data that are being processed, there will be from two to five pathways
specified in a single AERMET control file. A seventh pathway, MERGE, is a legacy of
AERMET prior to the 21DRF version (AERMET version 21112 and earlier). If AERMET
(21DRF and later) detects the MERGE pathway, it is ignored.
The records within a pathway make use of a key w oi cl and parameter approach for
specifying the input to AERMET. The keywords and parameters that make up this file can be
thought of as a command language through which the user directs AI-RMET. It is the
combinations of keywords and parameters thai direct AERMET how to process the data.
However, there are several rules of syntax thai must he obser\ ed for Al-RMI-T lo correctly
process the data.
2.2.1 Control file setup
While the control file has been designed lo pro\ ide the user with flexibility in the way it
is structured, there are some hasic syntax rules thai must be followed. These rules standardize
the formal of the control file These rules are
The pathway identifier appears on a line by itself followed by all the input records
lor that pathway In other words, all the records for a particular pathway must be
contiguous without any intervening keywords for other pathways.
l-ach record in the control file cannot exceed 500 characters in length. Prior to
Al-RMI-T 211)RIthe limit was 132 characters in length. The record can begin in
any column, so long as the entire length of the record, including leading blanks,
does not exceed 500 characters. For example, records starting with keywords can
be indented for readability (as is done throughout this user's guide). Each field on
a record must be separated by one or more spaces or a comma and must appear in a
particular order (with a few exceptions as noted later in the user's guide).
Blank records can be included anywhere in the control file to improve readability.
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If asterisks appear in columns 1 and 2 (**), AERMET ignores the statement. By
using the asterisks, the statement acts as a comment, which can be used to identify
the purpose of the control file, clarify the content of an individual keyword, or
ignore a keyword if the user edits a control file but wants to preserve the prior
content.
Alphabetical characters can appear in either upper or lower-case letters.
AERMET converts these characters to upper case (which is why any information
echoed to an output file is all upper case) lo insure exact matches on keywords and
parameters. However, beginning with version 21 l)RI\ AERMET retains the
original case of character strings associated with filenames. This is to allow
AERMET to work more efficiently with I .inux or I AIX. which are case sensitive.
Some keywords are mandatory, u hi le others are optional A keyword is
mandatory to the extent that there are data to process for the pathway and without
the keyword, the eventual product from .\I-R\II-T (the output files from Stage 2)
could not be generated. Optional keywords are used to include or extend data
processing actions. Most of the keywords used in the tutorial are mandatory. Some
keywords are repeatable. such as the keywords to specify the format of any site-
specific data, while others may only appear once These terms are discussed in
more detail in Section 3.0. Keywords In pathway are provided in Appendix A and
are identified as mandatory or optional. repealaMe or nonrepeatable.
Tn general, the order of keywords within a pathway is not important, though there
are a lew exceptions for the ONSITI- (PROG) and METPREP pathways. These
keywords pertain to the \ ariables and format of the site-specific (prognostic) data
in Stage I and the surface characteristics on the METPREP pathway in Stage 2.
I 'ilenames must conform to the naming conventions appropriate to the computing
platform and cannot exceed 300 characters in length. Prior to version 21DRF, the
filenames could not exceed 96 characters in length.
2-4
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3.0 Keyword reference
3.1 Definitions and control file processing
The terms "mandatory" and "optional" indicate whether the keyword for a particular
pathway is required to run AERMET (mandatory) or if it enhances or modifies the processing
(optional). Several keywords may be mandatory or optional depending on the point they are
used in the processing and the data. For example, QAOTT ser\ es two purposes: to define the
output file for Stage 1 QA and to define the input file lor Stage 2 calculations. While data QA is
optional in Stage 1, the keyword is mandatory if the Al-R\ll-T run is not a combined Stage 1
and 2 run. A distinction will be made when the keyword type may he ambiguous. For the
discussions in sections below, the stages to w liich the keyword refers will be in parentheses
following the terms "mandatory" and "optional" If'All' is specified, then the keyword applies
to all stages of processing.
The terms "icpealaMe" and "noniepealaMc" refer to whether the keyword can appear
only once (nonrepealaMe) or more than once (icpealaMe) for the same pathway in a control file.
For example, the Ml-SS.Uil-S keyword can appear only once on the JOB pathway, thus it is
nonrepeatable. Ho\\e\ er. the R.\\(.il- keyword for assessing the validity of the data can appear
multiple limes on a pathway, thus it is rcpealaMe A nonrepeatable keyword may appear
multiple times in a control file, but only once per pathway. For example, the QAOUT keyword
defines the input file lor each pathway for Stage 2 (merging data). It can appear only once for
each pathway, but it will appear two or three times in the control file because there is usually
more than one type of data to use in Stage 2.
Except for a few keywords, there are no special requirements for the order of the
keywords within each pathway, but it is recommended that a logical order be maintained to be
able to understand the processing defined by each control file.
The syntax descriptions in the following sections use certain conventions. The keywords
are all uppercase and the parameters are all lower case. Square brackets around a parameter
indicate that the parameter is optional, and a default value may be used if it is omitted.
3-1
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A word of caution that deserves repeating: for an AERMET run, all output files are
opened with STATUS = 'UNKNOWN'. With this specifier, if the file already exists, AERMET
will open it without providing any opportunity to save it. With the first write action to the file,
the contents of an existing file are erased. Before running AERMET. the user should be certain
that any output file name specified in a control file either does not exist or can be overwritten.
3.2 JOB Pathway
The JOB pathway appears in all AERMET control files The primary purpose of the
JOB pathway is to specify the file names for reporting all the preprocessor actions that are
performed for that particular run.
3.2.1 MESSAGES
All error, warning, informational, and OA messages issued by AERMET are written to
the file name specified with the MI-SS.\Cil-S keyword The contents of this file are discussed
throughout the tutorial in Section 4 n This keyword is mandatory because the program later
uses this file to summarize the processing The syntax and type are:
Syntax:
MISS ACil
'.S iiics.
-------
such as surface characteristics. The contents of a run summary are discussed throughout the
tutorial in Section 4.0. The syntax and type for this keyword are:
Syntax:
REPORT summary filename
Type:
Optional (All), Nonrepeatable
The summaryJilename must conform to the naming coin unions appropriate to the computing
platform. The maximum length of this file name is 300 characters
This keyword is optional. If it is omitted. then the summary is written to the output
control device connected to logical unit 6. On a personal computer, this unit is normally the
video monitor. This information can be captured using redirection (as discussed in
Section 4.0Error! No bookmark nnmc given.).
3.2.3 CHK SYNTAX
AERMET processes all the slalemenls in a control lile prior to processing any data.
Incomplete information on a keyword or the omission of a keyword will cause AERMET to
terminate the run The CI IK SYYI'.W keyword directs AERMET to process the control file
and report any problems without performing any data processing. The user can review the
summary and message files and correct any errors or make any changes to the control file prior
to processing data The syntax and type of the CHKSYNTAX keyword are:
Syntax:
CI IK SYNTAX
Type:
Optional (All), Nonrepeatable
No parameters accompany this keyword.
The user gets a full report of the processing of the control file, i.e., the MESSAGES file
and REPORT file are generated and can be reviewed. In the REPORT file, the following
appears near the top of the file:
3-3
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THIS RUN ONLY CHECKS THE RUNSTREAM INPUT
3 .2.4 NOPRINT
Beginning with version 21DRF, AERMET will suppress output to the screen. This
usually is the progression of operations through each day The synlax and type of the
NOPRINT keyword are:
Syntax:
NOPRINT
Type:
Optional (All), Nonrepealahle
No parameters accompany this keyword
3.2.5 DEBUG
Beginning with \ ersion 21 DRI\ AI-RMI-T lias a debug option that will output certain
calculations and messages from Stage I and most calculations in Stage 2 to a debug file. The
syntax and type lor this keyword arc
Syntax:
1)1 Mil Ci
Or
1)1.IH (> debugJilename
Type:
Optional (All), Nonrepeatable
Note that the DEBUG keyword can be followed by an optional filename. If the filename
is not listed, the default filename is aermet_debug.txt. When the debug keyword is used for
Stage 1 processing, the following is output to the debug file:
3-4
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When calculated upper air variables, speed shear, direction shear, and lapse rate
are audited, AERMET outputs the variables and calculations for those variables.
When reading ISHD data, AERMET will output messages to the message file
regarding replacement of observations with report type.
When reading sub-hourly site-specific data, AERMET will output the values
used for hourly averaging of sub-hourly variables.
When the DEBUG keyword is used with stage 2 processing, AERMET will output the
following to the debug file:
Upper air sounding used for each day
Value and source of key obsen ed \ ariables such as winds, temperature, pressure,
cloud cover, precipitation, etc.
Values are used for temperature and cloud co\ er substitution
Solar angle, critical undo, and resulting coin ecti\ e'stable assignment for each
hour
Calculations lor \ ariahles such as surface friction velocity, convective velocity
scale, mechanical and convecti\e mixing heights, etc.
The debug option will output for each day and hour designated by the XDATES
keyword The debug file can become quite large so the debug option should be used with care.
3.3 SI Ul A( I. pathway
The SI RI'ACI- pathway defines all the necessary information for processing NWS
hourly surface weather ohser\ ations or surrogate data that complies with an established format.
These data provide information on temperature, winds, and cloud cover (particularly important)
that can be used in estimating dispersion parameters. The data generally come from first order
observation stations (observations 24 hours per day) located at or near airports. AERMET can
read and process a variety of formats, each discussed below with the DATA keyword.
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3.3.1 DATA
Hourly NWS surface observations are stored in a variety of compact formats. Data
stored in one of these formats is referred to as archived data. One of AERMET's functions is to
read and interpret the archived data and to write the results in another format for later
processing. The DATA keyword is used to specify the file name and define the archive file
format for AERMET. The syntax and type for the DATA key w oi d are:
Syntax:
DATA archive filename file J or nun /. I.V )S/
Type:
Mandatory* (Stage 1 only; Stage 1 and 2 combined), Nonrepeatable
The archiveJilename must conform to the naming conventions appropriate to the computing
platform. The maximum length of the archive filename is 3<><> characters. The keyword is
mandatory under certain conditions and is optional under other conditions. The keyword is
mandatory if performing Stage 1 processing (separately or in a combined Stage 1 and 2
AERMET run) and the EXTRACT keyword (Section 3 3 2) is not used or the file associated
with the EXTRACT keyword is empty The DATA keyword is optional if the EXTRACT
keyword is present and the file associated with the EXTRACT keyword is not empty. In that
case, the data in the file associated with the l-XTRACT keyword is the input data.
I or processing archi\ e data, the file Jormat must be specified as one of the following:
CD144. l-XTRACT. SCRAM. SAMSOY HUSWO, or ISHD. Each of these formats is
discussed in more detail below beginning with version 21DRF, a new format, EXTRACT can
be used This can be used to read in NWS data in the format of the EXTRACT or QAOUT file
generated by AERMET Also beginning with AERMET version 21DRF, two formats, 3280VB
and 3280FB are no longer supported due to their age.
AERMET includes a table of ASOS commissions dates used to identify whether NWS
surface data input to AERMET are from an ASOS site. The ASOS parameter is applicable only
for the ISHD format and is used to identify the data as having originated from an ASOS site for
stations that are not included in the table of ASOS commission dates. The optional ASOS
parameter should only be used if the data are known to be from an ASOS site that is not
3-6
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included in the table of ASOS commission dates. Wind speeds collected at ASOS sites,
archived in the ISHD format, are truncated rather than rounded to whole notes (NOAA, 2008).
This introduces a bias in the data toward lower wind speeds. To compensate, AERMET adds V2
knot (0.26 m/s) to all ASOS-based wind speeds. A more detailed discussion of this adjustment
to ASOS wind speeds is in Section 3.7.11Error! Reference source not found..
NOTE: In earlier versions of AERMET, the DATA keyword included the blocking factor and
data type (ASCII or EBCDIC) parameters. These are 110 longer supported by AERMET,
beginning with version 11059. The default values for these parameters are 1 for blocking factor
and ASCII for data type. AERMET will issue a warning message iI"these parameters are
included with the DATA keyword.
3.3.1.1 CD-144 and SCRAM formats
The CD144 format is an older standard format previously used by the NCEI for
archiving surface obser\ ations Alphanumeric characters are used to represent various weather
elements. All the cut her elements for one hour are stored 011 one logical record and the length
of each logical record is 7l) characters
The SCRAM format is a reduced \ ersion of the CD144 format and is available from the
EPA's Support Center lor Regulatory Air Models (SCRAM) website. Fewer weather elements
are reported luich logical record is 2K characters and includes data for cloud ceiling height, dry
bulb temperature, wind speed and direction, and opaque sky cover. AERMET requires surface
station pressure lor some of its computations (e.g., density of air). The SCRAM format does not
include station pressure and sea le\ el pressure in a standard atmosphere (1013.25 millibars) is
assumed when this formal is used.
AERMET operates on a 01 - 24 clock but these two formats report data on the 00 - 23
clock. Hour 00 is hour 24 of the previous day. In previous versions of AERMET, when data
were retrieved from an archive file for a specific period, the first hour was discarded since it was
prior to the beginning time. Likewise, since the data for a day end with hour 23, the last day in
the extracted data file would only have 23 hours. This has been changed with AERMET 21DRF
3-7
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in that the conversion from 00 - 23 to 01 - 24 takes place before comparing the data's dates
against the processing dates.
AERMET reads several of the columns in the CD-144 format as character since numbers
or letters could appear in those columns. AERMET then attempts to decipher/decode these
columns by comparing the character it has read with a list of valid characters. If there is no
match, then AERMET issues a warning on which oveipunch position could not be deciphered.
The following table lists the correspondence between the o\ eipunch character and column in the
CD-144 format. Note: The term 'overpunch' refers to the "old" da\ s when 80-column computer
cards were used and the amount of information on a single card was limited. Overpunches
conserved space and were produced by pressing the overpunch key and pressing a numeric
value (0-9) and another key, usually the sign of the number This overpunch technique
generated a character rather than a numeric value, w liieh is u hat AERMET is trying to decode.
OveiDunch
CD-144
CD-144 element
1-3
14-16
Ceiling height
4
17
First sky cover layer
5
IS
Second sky cover layer
o
N
Third sky cover layer
7
20
Fourth sky cover layer
S
3o
Sign of the dew point (X i dew
9
41
1st digit of wind speed (Xi speed
1(1
47
Sign of the dry bulb (X i dry bulb
11
50
Sign of the wet bulb (X i wet bulb <
12
56
Total sky cover
13-34
57-78
Cloud data by layer
35
79
Opaque sky cover
The data associated with overpunches 9, 10, 12, and 35 (in bold above) may be used by
AERMET, depending on the availability of other (e.g., site-specific) data. The other fields are
decoded, but the weather information contained in them currently are not used by AERMET.
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3.3.1.2 SAMSON format
As storage technology and capacity improved, larger amounts of data can be stored in
smaller amounts of space. The NCEI made available solar and meteorological data for the first
order stations in the United States for the period 1961-1990 on a set of three CD-ROMs,
collectively referred to as the Solar and Meteorological Surface Observational Network
(SAMSON) dataset. This disc set is still available from the \CT.I. and AERMET can process
the data retrieved from these CD-ROMs.
> AERMET cannot access the data directly on a SAMSON CD-ROM.
Rather, the user must run the software provided with the data to retrieve the slation(s), period(s)
of time and variables for the site and period to be modeled. The software is a DOS-based,
interactive graphical interface. The oiiipul files are u lillen as an ASCII file on the user's local
drive. It is this output that AERMI - T processes
Retrieving the meteorological data lYom the CD-ROM is completely under the control of
the user, i.e., the user specifics u liich meteorological elements to retrieve from a list of 21
elements stored for each station When processing SAMSON data with AERMET, the
following elements should he rcliic\ cd ceiling height, wind direction and speed, dry bulb
temperature, opaque cloud co\cr. total sky co\er. and station pressure. These elements result in
an ASCJI file of about 450 Kb lor one year of meteorological data. If all 21 variables are
retrieved, then a file size of about I 2 Mb is created, although the file size will vary because
precipitation data (in field 21) are reported only if there was precipitation for the hour, making
some records longer than others
When the data are retrieved from the CD-ROM, two records are written at the beginning
of the file that identify the station (first record) and the variables retrieved (second record).
These two initial records, or headers, begin with the tilde character (~). AERMET processes
both records to obtain information about the station (e.g., station WBAN number) and to
determine how to process the data that follow. It is imperative that the user not alter or delete
these records.
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If more than one year of data are retrieved from the CD-ROM, then two records
beginning with the tilde appear before each year in the file. When the second set of headers is
encountered, AERMET will print a warning in the message file and continue processing data. It
is recommended that the user restrict data retrieved from CD-ROM to one station and one year
per file or edit a multi-year file such that there is only one year per file.
The header records are followed by the data records There is one record for each hour
of the period the user retrieved. Unlike the CD-144 formal u liich reports the hour on the 00-23
clock, the hour is reported on the 01-24 clock, which is consistent with AERMET data
processing.
3 .3 .2 EXTRACT
The EXTRACT keyword specifics the file name to u liich the data retrieved from the
archive file are written. The syntax and type are
Syntsix:
|-.\TR.\( I extracted data filename
Mandatory(Stage 1 only). Nonrepeatable
Type:
Or
Optional (Stage 1 and 2 combined), Nonrepeatable
The extracted data filename must conform to the naming conventions appropriate to the
computing platlbrm The maximum length of this file name is 300 characters. Note that when
running AERMET lor stage I only, the EXTRACT keyword is mandatory. However, if
performing a combined Stage I and 2 AERMET run, the EXTRACT keyword is optional as
stage 2 will use the internal .UiRMET arrays to read extracted data from Stage 1.
3.3.3 XDATES
The amount of data extracted from an archive file can be limited by using the XDATES
keyword to specify the beginning and ending dates of the data to be extracted. The syntax and
type are:
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XDATES YB/MB/DB [TO] YE/ME/DE
Syntax:
Or
XDATES YB/MB/DB [-] YE/ME/DE
Mandatory (Stage 1 only), Nonrepeatable
Type:
Or
Optional (Stage 1 and 2 combined), Nonrepeatable
YB, MB and DB are the beginning year, month, and day. rcspccli\ cly, of the data to extract and
YE, ME, and DE are the ending year month and day, rcspccli\ cly Beginning with version
21DRF, the year must be entered as a four-digit integer (e g . 1l^2) The month is a one- or
two-digit integer corresponding to the month of the year and the day is the one- or two-digit day
of the month. The dates can be entered in various ways. The individual components of start
date or end date can be separated by spaces or the " " character or no separator at all. However,
the start date cannot be separated In spaces and the end date separated by or vice-versa.
Both dates must use the same delimiter The complete start date and end date can be separated
by a space, '-', or 1 lie word "TO" The case of the word "TO" can he upper, lower, or a mix of
cases. The following are \ alid methods to enter the dates, using January 1, 2020 and December
31, 2020 as the dates:
2<)2<) o| o| 2<)2<) 12 3 I
2<)2<) 01/01 TO 2<)2<) 12 I
2ii2ii ()I ()1-2020/12 31
2020 HI 01 TO 2I12D 12 31
2020 m HI 2I12D 12 31
2020 01 01 202D 12 31
20200101 20201231
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The following are invalid methods to enter dates, again using January 1, 2020 and December 31,
2020 as the dates:
2020/01/01 2020 12 31
2020 01 01 2020/12/31
2020/01/01 -2020 12 31
2020 01 01 -2020/12/31
2020/01/01 TO 2020 12 31
2020 01 01 TO 2020/12/31
The keyword is mandatory if performing stage 1 processing only They keyword is
optional if performing combined Stage 1 and 2 processing and XDATI-S is present for the
METPREP pathway. If XDATES is present for the MITPRI.P pathway, AL-RMI-T will use
those dates for extraction of surface data
3.3.4 LOCATION
The LOCATION keyword identities the meteorological station by the station's identifier,
latitude and longitude of the station, and a time adjustment factor used to adjust the data to local
standard time The syntax and type are.
Synlsix:
LOCATION sue id MI'S lat/long NWS long/lat \tadjust\ \elevation]
Type:
Mandatory (Stage 1). Nonrepeatable, Reprocessed
Order:
1 .allHide (lat) and longitude (long) can appear in either order
The site id is a five-to-eight-character alphanumeric specifier that identifies the station
for which data are to be extracted. For the standard formats listed on the DATA keyword, these
identifiers are five-digit WBAN (Weather Bureau Army Navy) numbers. Prior to version
21DRF, the site id must be specified with leading zeros to fill a minimum of five characters
(e.g., 03928 must be entered as 03928) since the field was read as a type character and not an
integer. This is no longer true beginning with 21DRF so 3928 can be entered as 3928, not
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03928. However, all characters of the site id should be numeric as AERMOD expects a
numeric value in the AERMOD control file which should match the ID of the SURFACE
station identifier in the surface file generated by AERMET. A master list of WBAN numbers
for stations throughout the world can be obtained from the NCEI.
The NWS station latitude (Iat) and longitude (long) can be entered in either order
because AERMET distinguishes between the two by the suffix on each: an N or S with the
latitude and W or E with the longitude. For example, "38 4\ SI lAV" would be interpreted the
same as "81.9W 38.4N" in AERMET. AERMET cannot use. nor does it recognize, "+" or
to discriminate between north and south and east and west Therefore, the latitude and longitude
should always be specified as positive numbers.
The parameter, tadjust, is an optional adjustment factor that is subtracted from the
reported hour to convert the time to local standard time The delimit value is zero if omitted
from the LOCATION keyword on the SI RI'ACI- pathway Though optional, it should be
included when the offset to local standard time is non-zero and u hen the last parameter,
elevation, is specified, which is also optional I or stations west of Greenwich, tadjust should be
specified as a positi \ e number A purl from ISIII). the standard NWS surface data formats
processed by AF.RMI-T report the time as local standard time. Therefore, tadjust is zero for all
standard NW S formats processed by AERMI-T. apart from the ISHD format, unless the data are
known to be reported for a time /.one that is not local standard.
The final parameter, elevation, refers to the station elevation above mean sea-level
(MSL), in meters, and is also optional with a default value of zero meters. Station elevation
should be included, howe\ er. when the actual station elevation is non-zero because it will be
used in the substitution hierarchy for missing station pressure (see Section 5.5 ).
3.3.5 OAOUT
One purpose of AERMET is to contribute to the quality assurance process by identifying
data that are out of range or suspect such that the user can determine appropriate steps to accept,
modify, or reject the data. The quality assessment (QA) is performed by including the QAOUT
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keyword in the control file. This keyword is also used to specify the input file to Stage 2. The
syntax and type for the QAOUT keyword are:
Syntax:
EXTRACT extracted dataJilename
Optional (Stage 1 only; Stage 1 and 2 combined),
Type:
Nonrepeatable
Mandatory (Stage 2 only) if reading SURFACE data,
Nonrepeatable
The qa outputJilename must conform to the naming coin entions appropriate to the
computing platform. The maximum length of this file name is 3<)() characters.
Quality assessment is an optional process and the user does not ha\ e lo perform a QA
prior to using the data in PBL calculations. However, this step is recommended to identify
possible errors in the data that are used lo derive the boundary layer parameters. Note that when
running AERMET for stage 1 only or a combined stage I and 2 run. the QAOUT keyword is
optional. For a combined stage 1 and 2 run. stage 2 will use the internal AERMET arrays to
read extracted data from Stage I I louder, if running AI-RMI-T lor stage 2 only, the QAOUT
keyword is mandatory for stage 2 to read the Q.Vd output.
.\i:kmi:t's().\ pn icedures include \ eiilying that the values of the weather elements are
not outside a range of 'acceptable' \ allies and keeping track of the number of missing values.
These checks operate on one obser\ ation period at a time, i.e., temporal variations of the data
are not checked
On the SURFACE pathway, when a quality assessment is performed, several of the
weather elements are automatically tracked (audited) and included in a summary of the QA
process. These elements are dry bulb temperature, wind speed, and wind direction. The hourly
value of each variable is compared to a missing value indicator and if the value is not missing,
then the value is compared to an upper and lower bound that define the range of acceptable
values. Each time a value is missing or violates one of the bounds, a message is written to the
message file defined by the MESSAGES keyword. The message includes the value, the
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violation, and the date and time of the meteorological record where the violation occurred. The
date is reported in the first field in the message. The number of times the weather element is
missing, exceeds the upper bound and exceeds the lower bound is tallied and reported in the
summary file defined on the REPORT keyword.
In the current version of AERMET there are no provisions for automatically replacing
missing values or adjusting values that are outside the range of acceptable values. It is up to the
user to review the QA summary information and, using sound meteorological principles and any
regulatory guidance, either retain or replace the value in question
There are default upper and lower bounds in AERMET, as well as a default missing
value indicator. These values can be changed In the user using the RAMil- keyword, as
described below. Also, the user can QA additional weather elements by using the AUDIT
keyword.
3 .3 .6 AUDIT
As mentioned in the pie\ ions section, there are only three weather elements that are
tracked by default (lin ing a OA The user can track additional weather elements for a particular
AERJVII-T run In specifying the element name with the AUDIT keyword. The syntax and type
for this keyword are
All)1T sfname 1 ... sfnamen
Sy ill six:
or
AUDIT ALL
Type:
Optional (Stage 1 or Stage 1 and 2 combined),
Repeatable
where sjhame 1, ..., sfname n are the internal AERMET names of the weather elements as defined
in Error! Reference source not found.Table B-l of Appendix B. As many names can be
specified on a single keyword that will fit within the 500-character limitation of a line. Since
this keyword is repeatable, more than one AUDIT keyword can be used to define all the
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additional elements to track. Beginning with version 21DRF, if the user wishes to audit all
variables, the user would enter the word ALL after the keyword AUDIT. The case of the word
ALL is case insensitive
While the AUDIT keyword can add weather elements to the QA, there is no method to
remove any of the default weather elements from the QA. They are always reported.
3 .3 .7 RANGE
The user can modify the upper or lower bound limits for the OA if the values are not
appropriate for the data. The missing value indicator can be changed as well and is the most
likely reason this keyword is used. These changes are accomplished using the RANGE
keyword. The syntax and type for the RANGE keyword arc
Syntax:
RANGE sfnamc low er hound <[ J upper hound missing indicator
Type:
Optional (Stage 1 or Stage 1 and 2 combined). Repeatable,
Reprocessed
where sjhame is the internal AI-RMI-T name of I lie weather element as defined in Table B-l of
Appendix li. low er hound and upper hound are the new lower and upper bounds to be used in
the QA. and missing indicator is a new missing \ a I Lie code. The special symbol "<" and the
optional " " indicate whether to exclude (' c) or include (<=) the lower and upper bound values
in the OA. i e . exclude or include the endpoints of the acceptable range of values. All
parameters must he specified lor this keyword; if a parameter is not changing, the default value
should he specified
Prior to version 21DRF, data for the SURFACE pathway were written as integers with
some variables having been multiplied by 10 when extracted to retain significant digits. Table
B-l provides information on which variables use a multiplier. The default upper and lower
bounds are multiplied also, therefore, the user must multiply any new upper and lower bounds
by the same multiplier when entering the data on the RANGE keyword. However, the
multiplier is not applied to the missing indicator. Beginning with version 21DRF, the data are
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written out as their actual values, i.e., recorded temperature in the EXTRACT or QAOUT file is
the actual temperature, not temperature multiplied by 10.
Several weather elements have been concatenated to form a single variable in the
extracted data Jile. These variables are noted in Table B-l and are related to cloud cover,
weather type and height (locate the double slash (//) in the descriptions). If the user wants to
modify the bounds and the missing value indicator through a RANGE keyword, these values
must be concatenated, also.
3.3.8 NO MISSING
Every time a bound is violated or a value is missing, a message is u rilien to the message
file (defined with the MESSAGES keyword). If one weal her element that is Hacked for
reporting (either by default or defined 011 an AUDIT keyword) is missing most of the time (e.g.,
station pressure in a SCRAM archi\e iile). the message file could heeome very large. To reduce
the number of missing \ akie messages and the size of the message Iile, the NOMISSING
keyword can be included lor the OA The syntax and type are
\() MISSING sjnumc 1 . sfnamen
Syntax:
Or
NO MISSING ALL
Type:
Optional (Stage 1 or Stage 1 and 2 combined), Repeatable
where sjhame 1, .. . sjnumew are the internal AERMET names of the weather elements to omit
from the message file liegi nni ng with version 21DRF, if the user wishes to suppress messaging
for all variables, then the w ord ALL can follow the keyword NO MISSING. Though the
NO_MISSING keyword suppresses messages written to the message file, a count of missing
values for audited variables are still tallied and included in the summary report file.
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3.4 UPPERAIR
The UPPERAIR pathway defines all the necessary information for processing NWS
rawinsonde (sounding) data. These data provide information on the vertical structure of the
atmosphere and are used to calculate convective mixing heights in Stage 2. The height,
pressure, dry bulb temperature, relative humidity (which is used to obtain dew point
temperature) and winds are reported. There are aboul 5<~> stations around the United States, and
most countries in the world have an upper air observation program The data are generally
collected twice daily, at 0000 GMT and 1200 GMT (these times are also referred to as 00Z and
12Z, respectively).
AERMET can read and process three formats, as discussed below with the DATA
keyword. However, surrogate data can be used il" the user can reformat data i nto a format that is
ready for Stage 1 QA (i.e., skip the extraction process). AI-RMI-T has been designed to accept
24 soundings per day. Note though, for AI-RMI-T to correctly read the file, the format should
follow the format described in Table (-2 in Appendix ('
3.4.1 DATA
WVS rawinsonde data are stored in a \ariety of formats. However, AERMET is
designed to read only three of those formats, plus data in the format of the EXTRACT file for
upper air data As with hourly surface observations, data stored in this format is referred to as
archived data AI-RMI-T reads and interprets the sounding data and writes it to a separate file
for later processing The DATA keyword is used to specify the file name and define the archive
file format for AERMI-T The syntax and type for the DATA keyword are:
Syntax:
DATA archive filename file format
Type:
Mandatory* (Stage 1 only; Stage 1 and 2 combined), Nonrepeatable
The archive Jilename must conform to the naming conventions appropriate to the computing
platform. The maximum length of the archive file is 300 characters. The keyword is mandatory
if performing Stage 1 processing (separately or in a combined Stage 1 and 2 AERMET run) and
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the EXTRACT keyword (Section 3.3.2) is not used or the file associated with the EXTRACT
keyword is empty. The DATA keyword is optional if the EXTRACT keyword is present and
the file associated with the EXTRACT keyword is not empty. In that case, the data in the file
associated with the EXTRACT keyword are the input data.
AERMET can process upper air data in the TD-6201, FSL, and new to version 21DRF,
the IGRA formats in addition to the EXTRACT format TD-6201 is now obsolete, though
historical data may exist in corporate and personal archi\ es Neither format is available from
the NCEI; however, historical and current upper air dala in I he I SI. format is available for
download, free of charge, from the online NOAA T.SRI. Radiosonde Database
(http://esrl.noaa.gov/raobs/). The format specifications are also available at that same web
address. IGRA data can be downloaded free of charge from the NCEI ftp scr\ cr
(ftp://ftp.ncei.noaa.gov/pub/data/i ) TD-6201 dala are stored either as fixed-length or variable
length records, and the file formal should he specified as either 6201FB or 6201VB,
respectively, file formal for upper air data in the I"SI.. IGRA. or EXTRACT format should be
specified as FS1.. IGRA. or EXTRACT respecli\ely
Note that hcuinninu with \ ersion 1 105'). the blocking factor and data type (ASCII or
EBCDIC) parameters ha\e Ixvn rcmo\ed from the DATA keyword specifications, and
AERMI-T no longer supports their use if specified In the user. A value of'1' for
blocking factor and 'ASCI I' lor data type have been coded into AERMET. AERMET will issue
a warning message if these parameters are included on the DATA keyword.
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3 .4.2 EXTRACT
The EXTRACT keyword specifies the file name to which the data retrieved from the
archive file are written. The syntax and type are:
Syntax:
EXTRACT extracted data filename
Mandatory (Stage 1 only). Nonrepeatable
Type:
Or
Optional (Stage 1 and 2 combined). Nonrepeatable
The extracted data Jilename must conform lo I lie naming conventions appropriate to the
computing platform. The maximum length of lhis file name is 300 characters Note that when
running AERMET for stage 1 only, the EXTRACT keyword is mandatory. I low ever, if
performing a combined Stage 1 and 2 AI-RMET run. the EXTRACT keyword is optional as
stage 2 will use the internal AERMI-T arrays lo read extracted data from Stage 1.
3.4.3 XDATES
The amounl of data extracted from an archi\ e file can be limited by using the XDATES
keyword to specify the beginning and ending dates of the data to be extracted. The syntax and
type are
\l) \Ti :s ) i> \ IB/DB [TO] YE/ME/DE
Svnlsix:
Or
XDATES YB/MB/DB [-] YE/ME/DE
Mandatory (Stage 1 only), Nonrepeatable
Type:
Or
Optional (Stage 1 and 2 combined), Nonrepeatable
YB, MB and DB are the beginning year, month, and day, respectively, of the data to extract and
YE, ME, and DE are the ending year month and day, respectively. Beginning with version
21DRF, the year must be entered as a four-digit integer (e.g., 1992). The month is a one- or
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two-digit integer corresponding to the month of the year and the day is the one- or two-digit day
of the month. The dates can be entered in various ways. The individual components of start
date or end date can be separated by spaces or the '/' character or no separator at all. However,
the start date cannot be separated by spaces and the end date separated by '/' or vice-versa.
Both dates must use the same delimiter. The complete start date and end date can be separated
by a space, '-', or the word "TO". The case of the word "TO" can be upper, lower, or a mix of
cases. The following are valid methods to enter the dates, using January 1, 2020 and December
31, 2020 as the dates:
2020/01/01 2020/12/31
2020/01/01 TO 2020/12/31
2020/01/01 -2020/12/31
2020 01 01 TO 2020 12 31
2020 01 01 -2020 12 31
2020 01 01 2020 12 31
20200101 202D123 I
The following are invalid methods lo enter dates, again using January 1, 2020 and December 31,
2020 as the dates
2<)2<) "I "I 2<)2<) 12 3 I
2<)2<) "I "I 2<)2<) 12 3 I
2<)2<) "I "I - 2<)2<) 12 3 I
2<)2<) "I "I - 2<)2<) 12 3 I
2020/01/01 TO 2<)2<) 12 31
2020 01 01 TO 2020/12/31
The keyword is mandatory if performing stage 1 processing only. They keyword is
optional if performing combined Stage 1 and 2 processing and XDATES is present for the
METPREP pathway. If XDATES is present for the METPREP pathway, AERMET will use
those dates for extraction of upper air data.
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3.4.4 LOCATION
The LOCATION keyword identifies the meteorological station by the station's identifier,
latitude and longitude of the station, and a time adjustment factor used to adjust the data to local
standard time. The syntax and type are:
Syntax:
LOCATION site id NWS lat/long .VIYS long lat [tadjust\
Type:
Mandatory (Stage 1 only; Stage 1 and 2 combined). Nonrepeatable,
Reprocessed
Order:
Latitude (lat) and longitude (long) can appear in either order
The site id is a five-to-eight-character alphanumeric specifier thai identifies the station
for which data are to be extracted. For the standard formats listed on the DATA keyword, these
identifiers are five-digit WBAN (Weather Bureau Army \a\ y) numbers. Prior to version
21DRF, the site id must be specified with leading zeros to lill a minimum of five characters
(e.g., 03928 must be entered as 03928) since the field was read as a type character and not an
integer. This is no longer true beginning with 21 l)RI so 3l)2S can be entered as 3928, not
03928. However, all characters of the site id should he numeric as AERMOD expects a
numeric value in the AI-RMOD control file which should match the ID of the UPPERIAR
station identifier in the surface 11 le generated l\\ ALRMLT. A master list of WBAN numbers
for stalions throughout the world can he obtained from theNCEI.
The NW S station latitude (/at) and longitude (long) can be entered in either order
because AERMI-T distinguishes between the two by the suffix on each: an N or S with the
latitude and W orE with the longitude. For example, "38.4N 81.9W" would be interpreted the
same as "81.9W 38.4N" in ALRMET. AERMET cannot use, nor does it recognize, "+" or
to discriminate between north and south and east and west. Therefore, the latitude and longitude
should always be specified as positive numbers.
The parameter, tadjust, is an optional adjustment factor that is subtracted from the
reported hour to convert the time to local standard time. The default value is zero if omitted
from the LOCATION keyword on the SURFACE pathway. Though optional, it should be
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included when the offset to local standard time is non-zero. For stations west of Greenwich,
tadjust should be specified as a positive number. Apart from EXTRACT, the standard NWS
upperair data formats processed by AERMET report the time as GMT. Therefore, tadjust should
be non-zero for all standard NWS formats processed by AERMET, apart from the EXTRACT
format, unless the data are known to be reported for a time zone that is not local standard.
Note that beginning with version 11059, AERMET 110 longer supports the user-specified
station elevation as a parameter on the UPPERAIR LOC ATION keyword. AERMET will issue
a warning message if the elevation field is included The user-specified elevation will be
ignored, and processing will continue.
3.4.5 OAOUT
One purpose of AERMET is 10 contribute to the quality assurance process by identifying
data that are out of range or suspect such thai the user can determine appropriate steps to accept,
modify, or reject the data The quality assessment (OA) is performed by including the QAOUT
keyword in the conlrol file This keyword is also used to specify the input file to Stage 2. The
syntax and type for the QAOl T keyword are
Synlsix:
O AOl T exti'aciei/ data filename
Optional (Stage 1 only; Stage 1 and 2 combined),
\0111cpcalaMc
Type:
Mandatory (Stage 2 only) if reading UPPERAIR
data. Nonrepeatable
The qa output filename must conform to the naming conventions appropriate to the
computing platform. The maximum length of this file name is 300 characters.
Quality assessment is an optional process and the user does not have to perform a QA
prior to using the data in PBL calculations. However, this step is recommended to identify
possible errors in the data that are used to derive the boundary layer parameters. Note that when
running AERMET for stage 1 only or a combined stage 1 and 2 run, the QAOUT keyword is
optional. For a combined stage 1 and 2 run, stage 2 will use the internal AERMET arrays to
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read extracted data from Stage 1. However, if running AERMET for stage 2 only, the QAOUT
keyword is mandatory for stage 2 to read the QA'd output.
AERMET's QA procedures include verifying that the values of the weather elements are
not outside a range of'acceptable' values and keeping track of the number of missing values.
These checks operate on one observation period at a time, i.e., temporal variations of the data
are not checked.
Unlike the SURFACE pathway, there are no variables that are tracked (audited)
automatically on the UPPERAIR pathway. The user musl specify \ ariables to QA through the
AUDIT keyword, as discussed below. For each of the specified variables, the value of each
variable at each level is compared to a missing \ alue indicator and if the \ al Lie is not missing,
then the value is compared to an upper and lower bound thai define the range of acceptable
values. Each time a value is missing or \ iolales one of the bounds, a message is written to the
message file containing the value, the \ iolalion. the dale and lime of occurrence and the
sounding level. The number of limes the \ ariable is missing, exceeds the upper bound and
exceeds the lower bound is tallied and reported in the summary lile (defined on the REPORT
keyword).
The number of le\ els in a sounding and the heights at which the data are recorded vary
from sounding to sounding It is imp radical to report on every level. AERMET divides the
atmosphere into I n layers in u hich to summarize the QA information for the soundings. These
layers are based on the thickness increment defined to be 500 meters (in the variable UPINC in
module UPPERAIR) Th ese layers are: surface (the first level in the sounding), every 500
meters up to 4000 meters and everything above 4000 meters. By changing the value of UPINC
(and recompiling the software), these regions could be increased or decreased.
In the current version of AERMET there are no provisions for automatically replacing
missing values or adjusting values that are outside the range of acceptable values. It is up to the
user to review the QA summary information and, using sound meteorological principles and any
regulatory guidance, either retain or replace the value in question.
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There are default upper and lower bounds in AERMET, as well as a default missing
value indicator. These values can be changed by the user using the RANGE keyword, as
described below. Also, the user can QA additional weather elements by using the AUDIT
keyword.
3.4.6 AUDIT
As mentioned in the previous section, there are 110 upper air variables that are tracked by
default during a QA. The user can track some or all variables lor a particular AERMET run by
specifying the element name with the AUDIT key w oi cl The syntax and type for this keyword
are:
AUDIT umamc\ . uivninicn
Syntax: or
AUDIT Al l.
T Optional (Sta<>e I or Staue I and 2 combined),
yP°: RepeataMc
where uaname 1, ..., uunamc 11 are the internal AI-RMI-T names of the weather elements as
defined in Table TJ-2 in Appendix li As many names can be specified on a single keyword that
will lit within the 5<)()-characler limitation of a line Since this keyword is repeatable, more than
one Al l)IT keyword can be used to define all the additional elements to track. Beginning with
version 2IDIU. if th e user w ishes to audit all variables, the user would enter the word ALL after
the keyword Al DIT The case of the word ALL is case insensitive
3.4.7 RANGE
The user can modify the upper or lower bound limits for the QA if the values are not
appropriate for the data. The missing value indicator can be changed as well and is the most
likely reason this keyword is used. These changes are accomplished using the RANGE
keyword. The syntax and type for the RANGE keyword are:
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Syntax: RANGE uaname lower bound <[=] upper bound missing indicator
Type: Optional (Stage 1 or Stage 1 and 2 combined), Repeatable, Reprocessed
where uaname is the internal AERMET name of the weather element as defined in Table B-2 in
Appendix B, lower bound and upper bound are the new lower and upper bounds to be used in
the QA, and missing indicator is a new missing value code. The special symbol "<" and the
optional "=" indicate whether to exclude (<) or include ( ) the lower and upper bound values
in the QA, i.e., exclude or include the endpoints of the acceptable range of values. All
parameters must be specified for this keyword; if a parameter is not changing, the default value
should be specified.
Prior to version 21DRF, data for the \ PIM-R ATR pathway were w rilien as integers with
some variables having been multiplied by 10 when extracted to retain significant digits. Table
B-2 provides information on which \ ariaMes use a multiplier The default upper and lower
bounds are multiplied also, therefore, the user must multiply any new upper and lower bounds
by the same multiplier when entering the data on the R.Wil- keyword. However, the
multiplier is not applied to the missing iinhcaior. lieuinninu with \ ersion 21DRF, the data are
written out as their actual \ allies, i e . recorded temperature in the EXTRACT or QAOUT file is
the actual temperature, not temperature multiplied l\\ l<>
3.4.8 NO MISSIMi
Every time a hound is \ iolated or a value is missing, a message is written to the message
file (defined with the \ ll-SS.\(il-S keyword). If one weather element that is tracked for
reporting (either by default or defined on an AUDIT keyword) is missing most of the time (e.g.,
station pressure in a SCRAM archive file), the message file could become very large. To reduce
the number of missing value messages and the size of the message file, the NO MISSING
keyword can be included for the QA. The syntax and type are:
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NO MISSING umamel ... umamen
Syntax:
Or
NO MISSING ALL
Type:
Optional (Stage 1 or Stage 1 and 2 combined), Repeatable
where uaname 1, uanamen are the internal AERMET names of llie weather elements to omit
from the message file. Beginning with version 21DRL. if ihe user wishes to suppress messaging
for all variables, then the word ALL can follow the keyword NO MISSING. Though the
NOMISSING keyword suppresses messages w rillen to the message file, a count of missing
values for audited variables are still tallied and included in the summary report file.
3.4.9 MODIFY
AERMET has been designed to check for oilier problems with the upper air data and
correct them if the MODIFY keyword is used. The MODIFY keyword directs AERMET to
'turn on' the process and perform some preliminary quality control as the data are extracted. The
syntax and type of llie keyword arc
MODIFY
Syntax:
MODIFY ALL
MODIFY actionl..action3
'I'vpc:
Optional (Stage 1; Stage 1 and 2 combined),
Repeatable
By specifying this keyword, the following actions occur:
- DELMAND: Some mandatory levels are deleted from the sounding;
CALMDIR: A nonzero wind direction is set to 0 if the wind speed is 0;
SUB TTDD: Missing ambient and dew point temperatures are replaced by
interpolated values.
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If a mandatory sounding level is within one percent of a significant level (with respect to
pressure) then the mandatory level is deleted. This modification is performed to reduce the
possibility of reporting large gradients during the quality assessment (if the user opts to QA
those gradients). There is little loss of information in the sounding since mandatory levels are
derived from significant levels. However, the deletion process takes place after the data are
extracted from the archive data and reduces the number of levels extracted. AERMET does not
attempt to read more levels after deleting a level.
The wind speed and wind direction at each le\ el arc checked to ensure that there are no
levels with a zero wind speed and a non-zero i ncl direction If one is found, the wind direction
is set to zero to represent calm conditions. The u i litis from the souiuli nus are not used in any
boundary layer parameter estimates.
If the dry-bulb or dew-point temperature is missing al some level, then an estimate for
the missing temperature is made by linearly interpolating lo the level in question. The data from
the level immediately below and above the le\ el in question are used [f the data that are
required for the interpolation are also missing, then 110 interpolation is performed.
Prior to \ ersion 21 l)RI\ this keyword had 110 parameters associated with it. When the
keyword was specified, all three of the actions described abo\e occurred. Beginning with
version 21 l)RI\ there are se\ eral options to specifying the keyword. To invoke all three
actions, the keyword can be specified without any parameters, listing the word ALL after the
MODIFY keyword, or specifying all three actions (DELMAND, CALMDIR, and SUB TTTD).
To specify one or two actions, those actions are specified after the MODIFY keyword.
3.5 ONSITE or PROG
The ONSITE pathway provides a means of including data recorded during an
observation program such as might be required for dispersion modeling for a facility. Such a
program may utilize an instrumented tower (with data from several levels), a remote sensing
device (such as lidar), and instrumentation at or near ground level (such as measuring fluxes).
Much of this type of data can be used in AERMET to provide better estimates of the boundary
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layer parameters than using NWS data alone. As previously noted, the ONSITE pathway is also
used to process prognostic data processed via MMIF output in AERMET. Beginning with
version 21DRF, a new data path, PROG was added to AERMET. The PROG pathway is used
when processing prognostic meteorological data. Prior to version 21DRF, prognostic data was
processed in AERMET via the ONSITE pathway. To facilitate the use of prognostic
meteorological data over water and to let AERMOD know prognostic data are being used, the
PROG pathway has been added to AERMET. The two path w ays. ONSITE and PROG use the
same keywords, so instructions and descriptions are applicable lo hoth pathways. Throughout
the remainder of this section, when referring to the ONSITI- pathway, it is understood it applies
to the PROG pathway as well. Note that if AI-RMI-T encounters both the SURFACE and
PROG pathways in a control file, AERMET will issue an error and ahum processing. The
SURFACE pathway can only be used in conjunction w ilh the ONSITE pathway The
UPPERAIR pathway can be used with cither the ONSITI- or PROG pathway
There are several keywords thai are nearly identical to those found on the SURFACE
and UPPERAIR pathways, and there are se\ era I keywords that are unique for this type of data.
The only additional statements that must he included lor site-specific data are those required to
describe the structure of the data and a minimum detectable wind speed. All other statements
are optional and could he omitted
3.5.1 DATA
The file containing the site-specific data is specified on the DATA keyword. Unlike the
SURFACE and I PIM-RAIR pathways, there is no standard format or content for site-specific
data. Thus, only the file name is specified on this keyword. The syntax and type for the DATA
keyword are:
Syntax:
DATA datafilename [land water flag]
Type:
Mandatory (Stage 1; Stage 1 and 2 Combined), Nonrepeatable
The dataJilename must conform to the naming conventions appropriate to the computing
platform. The maximum length of this file name is 300 characters.
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Beginning with version 21DRF, there is an optional land/water flag that can be used in
conjunction with the DATA keyword. This flag denotes if the data are land based (OL) or water
based (OW). If there is no flag present with the DATA keyword, the data are considered land
based. If the OW flag is indicated and the pathway is ONSITE, then AERMET will issue an
error and abort. The overwater flag can only be used with the PROG pathway. The OL flag can
be used with ONSITE or PROG.
The purpose of the overland or overwater flag is lor boundary layer calculations in Stage
2. Certain input variables such as Monin-Obukhov length. u potential temperature lapse rate,
hourly surface characteristics (zo, albedo, and Bow en ratio), sensible heat flux, and latent heat
flux are only used if the data are over water. I f the data are over land and these variables are
present in the prognostic input data, then they are ignored in Stage 2 and they are calculated as if
they were not present in the input data. AERMET will issne a message in Stage 1 that the
variables will be read but not used and Stage 2 will also do the same. See Table B-3 and Table
B-4 in Appendix B for a list of variables that are used o\ er water
This new feature of AI-RMI-T is used in conjunction with the Mesoscale Model
Interface, orMMIF (Ramholl. 2<>21) \ersion 4 n or later he\ious versions ofMMIF will not
output the \ariaMes that are used for o\ em liter
3.5.2 I M KACT
I illike SI RI'ACE and I PPERAIR data, site-specific data are not stored (archived) in
any particular format. Therefore, the data are not "extracted" from an archive file, and there is
no need for the EXTR ACT keyw ord. The processing can begin with the quality assessment.
Thus, the input file to the QA is defined on the DATA keyword.
3 .5.3 READ and FORMAT
One of the more difficult challenges for many users attempting to run the AERMET
meteorological processor is to specify the inputs necessary to read and process site-specific, or
ONSITE, meteorological data. Since the AERMOD dispersion model was designed to utilize a
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wide range of site-specific meteorological variables, including wind, temperature, and
turbulence data from a multi-level tower and/or SODAR, it is not practical to specify a standard
format for site-specific data being input to AERMET. Also, since AERMET was written using
the Fortran programming language, part of the challenge may be for users to understand some of
the basic rules and concepts for reading data based on the Fortran language. This section
describes the process for defining ONSITE meteorological inputs for AERMET, including
enhancements introduced with version 11059 of AERMET that may simplify this process, and
provide better error handling and reporting if problems are encountered.
The key to reading site-specific meteorological data correctly in AERMET is to define
what data variables are present and specify the formal lor reading the data This task is
accomplished with two related keywords on the ONSI IT. pathway: 1) the RI.AD keyword,
which defines the list and order of variables present on a data record; and 2) the FORMAT
keyword, which defines the format of the data on each record As noted above, these two
statements together operate much like leading or u riling data in a Tortran program. The syntax
and type of these two keywords are as follows
Synt:i\:
READ record index osname\ osname2 ... osnamen
Type:
Mandators (Slagc 1 or combined Stage 1 and 2 ONSITE
piilliwa>). RcpcataMc. Reprocessed
Sy nl six:
1ORMAT record index Fortran_format
Typo:
Mandator) (Stage 1 or combined Stage 1 and 2 ONSITE
path\\a\), Repeatable, Reprocessed
Each READ keyword is paired with a corresponding FORMAT keyword through the
record index field. This index refers to one "record" of data for an observation period, although
the READ can span multiple records within the data file. The indices are numbered sequentially
beginning with 1. There can be up to 50 variables on any one data record and up to 50
"records" (or READs) per observation period. There is no fixed limit on the record length for
each physical record within the data file; however, some of the error handling and reporting
performed by AERMET for ONSITE data is limited to the first 500 characters of a given data
record.
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The osname 1, osname2, ... osnamen fields on the READ keyword are the variable
names for the variables included in the ONSITE data file for a particular data record, in the
order in which they are to be read. The variable names available for ONSITE data are described
in Table B-3 for "scalar" (single-level) variables and Table B-4 for "vector" (multi-level)
variables. The Fortranformat field on the FORMAT keyword is normally the Fortran format
statement that will be used to read the data from the corresponding READ keyword. However,
beginning with version 11059, users can specify 'FREE" (without quotes and not case-sensitive)
for the Fortran Jormat to indicate that the variables for a parliciikii" data record should be read
as free-formatted data, in accordance with Fortran language standards. Free-formatted, also
called list-directed data, are read as a list of values u hich are separated by at least one blank
space or by a comma. The user has the option lo specify FREE formal lor some data records,
while specifying the Fortran FORMAT explicitly lor other data records. The I 'RI E format
option may simplify the process of specifying the RI- AI) and I 'OIIMAT inputs for some users,
but still requires an understanding of some basic rules to ensure that the data are input properly
to AERMET.
The structure and formal of the site-specific data is reasonably flexible, but subject to the
following restrictions
(1) The data lor one ohser\ ation period can be spread across several records (up to
5
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time information can be listed on subsequent records for the period indicated on
the first line of the observation as well.
(5) The (non-date) data variables on the READ keywords must be a subset of those
listed in Table B-3 and Table B-4 in Appendix B, and are read as REAL format
(Fortran "F" or "E" format or as FREE format).
(6) Using an "F" or "E" (REAL) Fortran formal specifier to read a date/time variable
will cause an AERMET runtime error; and using an "I" (INTEGER) format
specifier to read a data variable will also cause an AI-RMET runtime error.
When specifying the multi-level variables, such as wind or temperature observations
from an instrumented tower, the variable name is composed of a two-character prefix that
identifies the atmospheric quantity and a two-character (numeric) suffix that identifies the level.
For example, height, temperature, and wind speed from the lust level would appear as HT01,
TT01 and WS01 on the RF.AD keyword, as IIT02. IT<)2 and \VS<)2 for the second level, and so
on. The same variables do not ha\ e to appear lor each le\ el of data. For example, winds may
appear at three levels lint temperature only at two le\ els. However, multi-level data must be
entered in ascending height order The different methods available for specifying the
measurement heights for ONSITI- data processed through AERMET are discussed in detail in
Section .1 5 I <)
Unless I RIL formal is specified for a particular READ, the Fortranformat on the
corresponding FORMAT keyword is a character string that AERMET uses directly within the
program to read the data I lence. the string must comply with all the rules of Fortran for
creating a format statement. The format must begin with an open parenthesis and end with a
closing parenthesis. Any book on the Fortran programming language can provide guidance on
constructing a format statement, but here are some important points to remember:
The Fortran "I" format specifier for integer constants consists of "I" followed by
the width of the data field, such that a format of "14" will read a 4-character data
string as an integer number.
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A read error will be generated if a non-numeric character (other than a leading "+"
or including a decimal occurs within the date field being read with an "I"
format.
The Fortran "F" format specifier for real constants consists of "F" followed by the
width of the field and number of places after the decimal point (Fw.d), such that a
format of "F5.2" will read a 5-character data string, including the decimal, as a real
number, with 2 places after the decimal point.
Data being read as real constants using the "I " formal specifier are not required to
include decimal places within the data siring. howe\ or, users must be aware of the
rules for assigning values using the "F" formal specifier in such cases:
o If the data string includes a decimal place, then the \ alue assigned to the REAL
variable will reflect the number of decimal places specified, e.g., reading the
string "10.23" as F5.2, F5.1, or I 5 n will all assign the \ allie 10 23 to the
variable.
o However, if the data si ling does not include a decimal point the number of
decimal places assigned will he hased on the TM format specifier, such that
reading the string "M<)23" (where "/>" represents a blank) asF5.2, F5.1, orF5.0
will assign the \allies in 23. 1 <»2 3. and I<>23 lo the variable, respectively.
Data being read as RI-AI. constants using the TREE" format option will reflect the
values as specified in the data file, such that a string of "10.23" will be assigned a
value of 11) 23. w hereas a string of" I "23" will he assigned a value of 1023.
Reading dale \ ariahles as INTEGER constants using the "FREE" format option will
not result in a read error if a decimal (".") occurs within the data field being read, but
any data after the decimal point will be ignored, such that a data field of "4.8" will be
read as an INTEGER value of 4. However, any other non-numeric character in the
data lield (other than a leading "+" or "-") will result in a Fortran read error.
The fourth bullet aho\ e related to the number of decimal places reflected in the data
highlights one of the more significant problems that could arise with reading ONSITE data in
AERMET, since the value assigned to the variable may not be the value intended by the user.
This situation may arise if the ONSITE data file has been generated by exporting data from a
spreadsheet program. In such cases the data values for a particular parameter may have a
varying number of decimal places, including values with no decimal places for some records,
since the spreadsheet program may output a fixed number of significant digits rather than a
3-34
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fixed number of digits after the decimal. While this issue could occur with any ONSITE data
variables, it may be more likely for parameters that vary over a large range, such as solar
radiation data. Given the potential problems that could arise if the data values being read by
AERMET may not match the values intended, users are strongly encouraged to review the
QAOUT file for the ONSITE data to ensure that the data have been read properly by AERMET.
The QA audit statistics on values exceeding the upper and lower bounds for a given parameter
may also highlight potential problems with the data. For cases when the "raw" ONSITE data
include a variable number of decimal places, using the "l-'RI'l-" format option or using "Fw.O" as
the Fortran format specifier may avoid the issue described abo\ e
Another issue that may arise with processing ONSITE data is that the missing data code
used within the data file does not match the del an 11 missing code used In A I - RMET (shown in
Table B-3 and Table B-4 in Appendix B). AERMET will process the "missing" value as valid
data in such cases, which may produce errors or anomalous results. The user can specify
missing indicators that differ from the default using the R.WCil- keyword on the ONSITE
pathway, and the QA audit statistics 011 \ allies exceeding the upper and lower bounds may also
highlight if such a problem exists I11 addition. AI-RMI-T will issue warning messages, which
are included in the REPORT files, for cases w hen the upper and lower bounds are exceeded by
an amount larger than one half the range defined by I I'PER-LOWER, which may flag this issue
in some cases
It may be the case that not all the \ ariables present in the site-specific data file need to be
read. Any superfluous data can easily be skipped using the "X", "T", and "/" specifiers in the
Fortran FORM AT statement I lowever, the "FREE" format option does not allow for skipping
values within the data record and assigns values to the variables based on the order of variables
within the data file. Also, users should note that:
> the same format used to read the original site-specific data file is also used to write
the QA output (QAOUT) file.
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3.5.4 XDATES
The amount of data extracted from a file can be limited by using the XDATES keyword
to specify the beginning and ending dates of the data to be extracted. The syntax and type are:
Syntax:
XDATES YB/MB/DB [TO] YE/ME/DE
Or
XDATES YB/MB/DB [-] )/.'.W/
Mandatory (Stage 1 onlv). Nonrepeatable
Type:
Or
Optional (Stage 1 and 2 combined), Nonrepeatable
YB, MB and DB are the beginning year, month, and day. respectively, of the data lo extract and
YE, ME, and DE are the ending year nionlh and day, respect i\ el v. Beginning with version
21DRF, the year must be entered as a four-digit integer (e.g . 1l^>2). The month is a one- or
two-digit integer corresponding to the month of the year and the day is the one- or two-digit day
of the month. The dales can he entered in various ways The indi\ idual components of start
date or end date can he separated l\\ spaces or the " " character or no separator at all. However,
the start date cannot he separated In spaces and the end date separated by '/' or vice-versa.
Both dates must use the same delimiter The complete start date and end date can be separated
by a space. or the word "TO" The case of the word "TO" can be upper, lower, or a mix of
cases The following are \alid methods to enter the dates, using January 1, 2020 and December
31, 2020 as the dates
2020/01/01 2020,12 31
2020/01/01 TO 2u2u/12/31
2020/01/01 -2020/12/31
2020 01 01 TO 2020 12 31
2020 01 01 -2020 12 31
2020 01 01 2020 12 31
20200101 20201231
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The following are invalid methods to enter dates, again using January 1, 2020 and December 31,
2020 as the dates:
2020/01/01 2020 12 31
2020 01 01 2020/12/31
2020/01/01 -2020 12 31
2020 01 01 -2020/12/31
2020/01/01 TO 2020 12 31
2020 01 01 TO 2020/12/31
The keyword is mandatory if performing stage 1 processing only They keyword is
optional if performing combined Stage 1 and 2 processing and XDATES is present for the
METPREP pathway. If XDATES is present for the MITPRI.P pathway, AL.R\II:T will use
those dates for extraction of site-specific or prognostic data
3.5.5 LOCATION
The LOCATION keyword identifies the meteorological station by the station's identifier,
latitude and longitude of the station, and a time adjustment factor used to adjust the data to local
standard time The syntax and type are.
Synlsix:
LOCATION sue id MI'S lat/long NWS long/lat \tadjust\ \elevation]
Type:
Mandatory (Stage 1). Nonrepeatable, Reprocessed
Order:
1 .allHide (lat) and longitude (long) can appear in either order
The site id is a five to eight-character alphanumeric specifier that identifies the station
for which data are to be extracted. Since data are not extracted from archived data, this
identifier is used only to identify the site in the output files (reports and from Stage 2). Prior to
version 21DRF, the site id must be specified with leading zeros to fill a minimum of five
characters (e.g., 03928 must be entered as 03928) since the field was read as a type character
and not an integer. This is no longer true beginning with 21DRF so 3928 can be entered as
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3928, not 03928. However, all characters of the site id should be numeric as AERMOD
expects a numeric value in the AERMOD control file which should match the ID of the
ONSITE station identifier in the surface file generated by AERMET.
The measurement site or prognostic grid cell's latitude (lat) and longitude (long) can be
entered in either order because AERMET distinguishes between the two by the suffix on each:
an N or S with the latitude and W or E with the longitude For example, "38.4N 81.9W" would
be interpreted the same as "81.9W 38.4N" in AERMET AI-RMI-T cannot use, nor does it
recognize, "+" or to discriminate between north and south and east and west. Therefore, the
latitude and longitude should always be specified as positi\ e numbers
The parameter, tadjust, is an optional adjustment factor that is subtracted from the
reported hour to convert the time to local standard ti me The default value is zero if omitted
from the LOCATION keyword on the SI RI'ACE pathway Though optional, it should be
included when the offset to local standard time is non-zero and u hen the last parameter,
elevation, is specified, which is also optional For stations west of (ireenwich, tadjust should be
specified as a positi\ e number The adjustment factor is subtracted from the reported hour.
Since there is no standard format for site-specific data, the time reported could be relative to any
time frame Tor example, one time frame the user should verify is if the data are reported in
local da\ liuhl time If this is the case, then lad/nsi could be specified as 1 to return the data to
local standard time, assuming that daylight time was used throughout the entire data period.
The I Inul parameter, eleven ion, refers to the station elevation above mean sea-level
(MSL), in meters, and is also optional with a default value of zero meters. Station elevation
should be included, howe\ er. when the actual station elevation is non-zero because it will be
used in the substitution hierarchy for missing station pressure (see Section 5.5).
3.5.6 OAOUT
As with the UPPERAIR and SURFACE pathways, AERMET can assess the quality of
the site-specific data by including the QAOUT keyword in the control file. This keyword is also
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used to specify the input file name to Stage 2. The syntax and type for the QAOUT keyword
are:
Syntax:
QAOUT extracted dataJilename
Optional (Stage 1 only; Stage 1 and 2 combined),
Type:
Nonrepeatable
Mandatory (Stage 2 only) if reading ONSITE or
PROG data, Nonrepeatable
The qa outputJilename must conform to the naming coin unions appropriate to the computing
platform. The maximum length of this file name is 3(JU characters. Note that when running
AERMET for stage 1 only or a combined stage I and 2 run, the QAOUT keyword is optional.
For a combined stage 1 and 2 run, stage 2 will use the internal .YERMET arrays lo read
extracted data from Stage 1. Howe\ er. i I'm lining AI-RMI-T for stage 2 only, the QAOUT
keyword is mandatory for stage 2 to read the Q.Vd output
Quality assessment is an optional process, and the user does not have to perform a QA
prior to merging the site-specific data Howe\ er. this step is recommended to identify any
possible problems with the data that are used to deri\ e the boundary layer parameters.
Presently. AI-RMI-T's capabilities in this area are limited to verifying the values of the
site-specilic data are not outside a range of acceptable values and keeping track of the number of
missing values These checks operate one observation period at a time, i.e., variations over a
period are not checked
Site-specific data max be reported more frequently than once per hour (see the
OBS/HOUR keyword discussed below in Section 3.5.13). For observations more frequent than
once per hour, the QA procedures operate on the sub hourly data and the hourly averaged data
as well.
When a quality assessment is performed on the site-specific data, several of the variables
are automatically tracked (audited) and included in a summary of the QA process. These
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variables are temperature, wind speed and wind direction. The value of each variable at each
level is compared to a missing value indicator and if the value is not missing, then the value is
compared to an upper and lower bound that define the range of acceptable values. Each time a
value is missing or violates one of the bounds, a message is written to the message file defined
on the MESSAGES keyword, which identifies the variable, the violation, and data and time of
occurrence. The number of times the variable is missing, exceeds the upper bound and exceeds
the lower bound is tallied and reported in the summary file defined by the REPORT keyword.
There are no provisions for automatically replacing missing site-specific values in
AERMET or adjusting values that are outside the range of acceptable \ alues. It is up to the user
to review the QA summary information and, using sound meteorological principles and any
regulatory guidance, either replace the value in question or leave it alone
There are default upper and lower hounds in AL-RMI-T. as well as a default missing
value indicator for each variable. These \ alues can be changed In the user using the RANGE
keyword, as described below (Section 3 5 S) The user can QA additional variables by using the
AUDIT keyword.
3 .5.7 AT T)TT
As mentioned in the pie\ ions section, there are only three weather elements that are
tracked In default during a OA The user can track additional weather elements for a particular
AERJVII-T run In specifying the element name with the AUDIT keyword. The syntax and type
for this keyword are
AUDIT osnamel ... osnamen
Syntax:
or
AUDIT ALL
Type:
Optional (Stage 1 or Stage 1 and 2 combined),
Repeatable
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where osname 1, osname n are the internal AERMET names of the weather elements as
defined in Table B-3 and Table B-4 in Appendix B. For the multi-level variables (e.g.,
temperature) only the two leading alphabetic characters can be specified (e.g., TT) or with a
level such as TT01, otherwise AERMET will terminate with an error. Every level where the
variable appears will be QA'd. As many names can be specified on a single keyword that will
fit within the 500-character limitation of a line. Since this keyword is repeatable, more than one
AUDIT keyword can be used to define all the additional elements to track. Beginning with
version 21DRF, if the user wishes to audit all variables, the user u ould enter the word ALL after
the keyword AUDIT. The case of the word ALL is case insensili\ e
While the AUDIT keyword can add weather elements to the OA. there is no method to
remove any of the default weather elements from the QA. They are alw nvs reported.
3.5.8 RANGE
The user can modify the upper or lower hound limits lor the QA if the values are not
appropriate for the data The missing value indicator can he changed as well and is the most
likely reason this keyword is used. These changes are accomplished using the RANGE
keyword The syntax and type for the RAMil- keyword are:
Syntax:
R.WCil- osname lower bound [=] upper bound missing indicator
Type:
Optional (Stage 1 or Stage 1 and 2 combined), Repeatable,
Reprocessed
where osname is the internal AI-RMET name of the weather element as defined in Table B-3
and Tu Me 15-4 in Appendix li. lower bound and upper bound are the new lower and upper
bounds to be used in the QA, and missing indicator is a new missing value code. The special
symbol "<" and the optional "=" indicate whether to exclude (<) or include (<=) the lower and
upper bound values in the QA, i.e., exclude or include the endpoints of the acceptable range of
values. All parameters must be specified for this keyword; if a parameter is not changing, the
default value should be specified. For the multi-level variables (e.g., wind speed and
temperature), only the first two characters should be specified (e.g., WS and TT).
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The default upper and lower bounds are multiplied also, therefore, the user must
multiply any new upper and lower bounds by the same multiplier when entering the data on the
RANGE keyword. However, the multiplier is not applied to the missing indicator.
3.5.9 NO MISSING
Every time a bound is violated or a value is missing, a message is written to the message
file (defined with the MESSAGES keyword). If one weather element that is tracked for
reporting (either by default or defined on an AUDIT keyword) is missing most of the time (e.g.,
station pressure in a SCRAM archive file), the message file could Ix-come very large. To reduce
the number of missing value messages and the size of the message file, the NOMISSING
keyword can be included for the QA. The synui\ and type are:
NO MISSING osnunh-l ... osiiaiiicn
Syntax:
Or
NO MISSING ALL
Type:
Optional (Stage 1 or Stage 1 and 2 combined). Repeatable
where sjhame 1, ..., sjiuimcn are the internal ALRMLT names of the weather elements to omit
from the message lile Ik-ginning with \ersion 211 )RI". if the user wishes to suppress messaging
for all \ ariables. then the word Al.l. can follow the keyword NO MISSING. Though the
NO_\IISSI\G keyword suppresses messages written to the message file, a count of missing
values lor audited \ ariables are still tallied and included in the summary report file.
3.5.10 OSHEIGHTS
AERMET provides two options for specifying the measurement heights for the multi-
level profile data input through the ONSITE pathway. One option is to explicitly specify the
measurement heights within the input data file, using the 'HTnn' variable on the READ
keyword, where 'HT' refers to the height variable and 'nn' refers to the level at which the
observation was taken, beginning with '01' for the first (lowest) level, '02 for the next lowest
level, up to the highest level (see Table B-4). With this option the 'HTnn' variables would need
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to be included for each observation period within the data file. While AERMET allows the
measurement heights to vary from one observation to the next with the 'HTnn' option (which is
normally not the case), the number of levels must be the same for each data period, and the
heights must be defined in increasing order from lowest height (HT01) to the highest height.
Under this option, if measurement heights are found to decrease with height or be duplicated, all
multi-level data for that observation period will be set as missing.
The OSHEIHGTS keyword on the ONSITE pathway pro\ ides an alternative approach
for specifying measurement heights for multi-level profi le data The syntax and type for the
OSHEIGHTS keyword are as follows:
Syntax: OSHEIGHTS height 1 height2 ... heightn
Optional if height in formal ion is pio\ idcd in I lie data; otherwise,
mandatory (Staijc I or Siulv 1 and 2 combined). Rcpeatable. Reprocessed
The heightl. heightn \ ariahlcs are the measurement heights in meters,
ordered from lowest to highest. If the OSIII-Kil ITS keyword is specified and the 'HTnn'
variables are also defined on the REM) keywords. AI-RMET will use the heights based on the
OSHI-IGIITS keyword to o\ enide the height \ ariaMes that may be present in the data file. For
example, if the heights in the data file are 10.0, 50.0 and 100.0 meters, but the user knows that
the heights are really Of). 50 o and I mi 0 meters, rather than modify the data file, the
OSHEIGHTS keyword can be used to rectify the problem.
3.5.11 DELTA I IMP
In addition to measuring ambient temperature directly, a site-specific data program may
measure differences in temperature. These measurements can be either between the levels
where the ambient temperature is measured or independently of these levels. Temperature
difference near the surface can be used to infer sensible heat flux. Measured temperature
differences are not the same as the ambient temperature difference between two levels. A true
temperature difference utilizes an instrument, such as a thermocouple, that couples two levels of
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data, whereas ambient temperature at two levels most likely is measured by two independent
instruments.
The ONSITE data pathway has provisions for up to three temperature differences, which
are defined through the three variables DT01, DT02 and DT03 (see Table B-4). The heights
that define the temperature difference cannot be entered directly through the READ and
FORMAT keywords. The special keyword DELTATFATP dell lies the two levels that comprise
the temperature difference. The syntax and type are:
Syntax: DELTA TEMP index low er height upper height
T # Optional (Stage 1 or Stage 1 and 2 Combined). Repeatable,
Reprocessed
Each statement includes an index thai corresponds lo llie temperature difference represented by
the lower and upper heights. The mi/ex can range from one lo three. At present, only DT01 is
utilized in Stage 2.
3.5.12 THRESHOLD
The threshold wind speed, the minimum wind speed required to detect air flow varies,
from anemometer to anemometer The user must specify the minimum detectable (threshold)
wind speed of the site-sped lie anemometer. There is no default value. The THRESHOLD
keyword is used for this purpose The syntax and type for this keyword are:
Syntax:
Tl IRI .SI [OLD threshold wind speed
Type:
Mandatory (Stage 1 or Stage 1 and 2 combined),
Nonrepeutable, Reprocessed
The THRESHOLD keyword must be included when site-specific data are
processed.
The threshold can be no greater than 1.0 m/s. A value greater than 1.0 generates an error
condition and AERMET does not process any data. For threshold values above 0.5 m/s,
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AERMET writes a warning message. For applications involving prognostic data, the
recommended threshold is 0 m/s (EPA, 2018) and AERMET will issue a warning if the
threshold is not equal to the recommended value.
AERMET also imposes a minimum allowable wind speed for defining the wind speed to
use in estimating the boundary layer parameters. This minimum is independent of the threshold
wind speed and is defined as 2m * ovmin, where ovmin= 0 2 m's
3 .5 .13 OBS/HOUR
Site-specific data may be reported more frequently than once per hour. If the data
include more than one equally spaced observation period each hour, the keyword OBS/HOUR is
used to specify the number of observations that AI-RMI-T should expect each hour. AERMET
currently allows up to 12 observation periods per hour (i e . e\ ery 5 minutes) and will calculate
the average over all periods within the hour lo produce an hourly a\ erage. At least half the
observations for a \ ariahle must not he missing for AI-RMI-T lo compute the average, otherwise
the value for the hour is set lo missing A discussion on how the a\ erage is computed for each
variable is in Section 5.4 If there is one obser\ alion period per hour, this keyword is optional.
The syntax and type for this keyword arc
Sv ill six:
OliS 1IOI R ii ohs |average method]
Type:
Mandatory for data with more than 1 observation per hour (Stage 1 or
Stage 1 and 2 combined), Nonrepeatable
All variables specified on the READ keywords must be reported at the same number of
observations per hour, e g . one \ ariable cannot be reported once per hour and the remaining
variables reported four times per hour.
Each hour of data must contain the same number of observation periods per hour. For
example, if the user specifies 4 OBS/HOUR, but there are only two observation periods for one
hour in the middle of the file, AERMET will not detect this condition and will not correctly
compute the hourly averages for all subsequent hours.
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Beginning with version 21DRF, there is an optional parameter that can be specified for
wind speed and wind direction averaging, scalar averaging or vector averaging. The default
averaging when no averaging method is specified is scalar averaging. Another way to specify
scalar averaging, is for the user to enter SCALAR after the number observations per hour. To
specify vector averaging, the user can enter VECTOR after the number of observations per
hour. The vector averaging approach is based on that discussed in Section 6.2.2 in EPA (2000).
If vector averaging is used, the VECTORWS modeling option should be used in AERMOD.
3.6 MERGE
Prior to version 21DRF, the MERGE pathway merged the upper air. surface, and any site-
specific data prior to the final stage METPRIV Ik-ginning with version 211 )RF. this pathway is
now obsolete. While executing, if AERMET encounters the MT.RGE pathway and associated
keywords, AERMET will alert the user and ignore them The warning messages are meant to
allow easier transition to use AERMI -T i npuls thai u ere formatted for AERMET versions prior
to 21DRF.
3.7 METPREP
This pathway is also referred to as Stage 2. w hen the boundary layer parameters are
estimated that will he used In the dispersion model. This is the second and final step in the
sequence of steps that began with extracli ng data from archived data files. Several of the
keywords seen on the pre\ ions pathways are also used on this pathway in a nearly identical
manner. Prior to \ ersion 21 l)RI\ this was what was called stage 3.
3.7.1 DATA
Prior to version 21DRF, this keyword was a reference to the output of the MERGE pathway.
This keyword is now obsolete and AERMET will ignore the keyword and associated datafile if
present in the AERMET control file.
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3 .7.2 MODEL
Although AERMET currently only estimates parameters for the AERMOD dispersion
model, it is designed with the capability to estimate parameters for other dispersion models.
The MODEL keyword informs AERMET for which model to process the data. The syntax and
type are:
Syntax:
MODEL model name
Type:
Optional (Stage 2 or Stage 1 and 2 combined),
Nonrepeatable
where model name identifies the dispersion model The AERMOD model is the default model,
making this keyword optional.
3.7.3 ASOS1MIN
Beginning with \eision I se\eral modifications ha\e hceii made to AERMET
related to the processing of surface ohser\ alions from Automated Surface Observing Systems
(ASOS) used to collect weather measurements at airports located within the U. S. The U.S.
NWS and I ,\.\ hegan an effort in ll^2 to replace the traditional observer-based system for
collecting and reporting weather data with an automated system. As of 2010, there were over
900 ASOS stations located at airports across the U.S. The transition from the observer-based
system to ail automated system has presented both challenges and opportunities in relation of
the use of such data to support dispersion modeling applications (EPA, 1997). This section
describes several modifications to AERMET to address some of these challenges, as well as to
take advantage of the opportunities, and the most significant changes are related to processing of
ASOS wind data.
In addition to the standard archives of surface observations based on ASOS, the NCEI
began routinely archiving 1-minute ASOS wind data (TD-6405), beginning with data for
January 2000 for first-order NWS ASOS stations, and beginning with data for March 2005 for
all other ASOS stations. The 1-minute ASOS wind data files include the 2-minute average wind
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speed and direction reported every minute, i.e., the files consist of 60 overlapping 2-minute
averages for an hour. By contrast, the standard archives of surface observations based on ASOS
include a single 2-minute average wind speed, usually reported within 10 minutes before the
hour. The values included in the 1-minute ASOS wind data files are reported to the nearest
degree for wind direction and whole knots for wind speed. More importantly, whereas the
standard ASOS archives report any wind speed below 3 knots as 0 knots to represent a calm,
consistent with the METAR standard adopted in July 1 C)CH\ the 1 -minute ASOS wind data files
include values for 1 knot and 2 knots.
The use of hourly-averaged wind speed and direction pro\ ides a more appropriate input
for the AERMOD dispersion model than a single 2-niinule average. I tilizing wind data for the
full hour will typically result in a more complete data set since many hours classified as calm or
variable (with a non-missing wind speed up to 6 knots, hut missing wind direction) based on a
single 2-minute average will be filled in with hourly a\ eraues derived from the 1-min ASOS
wind data. Furthermore, the use of hourly a\ eraued wind direction, deiived from 2-minute
averages reported to the nearest degree, eliminates the need to randomize wind directions as
done for the standard ohser\ ations which are reported to the nearest in degrees.
Beginning with \ersion I I<)51>. Al-RMI-T was updated to accept hourly averages of
wind speed and wind direction domed from I-minute ASOS wind observations available from
the NCI-1 at ftp Hp ncei noaa uo\ puh data/asos-onemin/. The hourly-averaged wind speed
and wind direction files input to Al-RMI-T should be generated using EPA's 1-minute ASOS
wind data processor. AERMIM Tli (EPA, 2015). Hourly-averaged wind speed and direction
data derived from 1-minute ASOS wind data files using AERMINUTE will be referenced below
as "1-minute ASOS wind data ""
The 1-minute ASOS wind data are read by AERMET during the Stage 2 merge
processing. AERMET is instructed to include these data in the merged output by adding the
ASOS1MIN keyword followed by the filename of the 1-minute ASOS wind data file on the
SURFACE pathway in the Stage 2 control file using the following format:
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Syntax:
ASOS1MIN file name
Type:
Optional (Stage 2 or Stage 1 and 2 combined), Non-repeatable
Must be input on the SURFACE pathway
When provided, 1-minute ASOS wind data can be used to substitute for missing ONSITE wind
data or replace wind data from standard NWS or FAA SURFACE data formats when ONSITE
data are not included. To substitute for missing ONSITE winds or replace standard SURFACE
winds, the secondary keyword REFLEVEL (Section 0) musl be specified with the SUBNWS
parameter as a METHOD on the METPREP pathway in the Stage 2 control file.
When SUBNWS is specified, AERMI-T uses the following hierarchy, based on data
availability for each hour, to select the wind data used to calculate boundary layer scaling
parameters, and ultimately written to the surface li le (SIC) generated during Stage 2 processing:
1. ONSITE winds,
2. 1-min ASOS wiiuls. then
3. standard SI Rl ACI' winds
Neither NWS SI Ul-ACT. wind nor l-min ASOS wind data will be used to substitute
for missing ONSITK wind data if the Ul l MATI. SUBNWS' option under the METHOD
keyword is oniilled from (lie Stage 2 control Hie.
Wind speeds from I -minute ASOS wind data files are extracted and merged during
Stage 2 processi ng
3.7.4 THRESH 1MIN
In 2003, NWS began replacing the traditional cup and vane wind instruments at ASOS
stations with more sensitive sonic anemometers (NOAA, 2003). Unlike the standard cup
anemometer, which has a nominal starting threshold of about 2 knots, sonic anemometers have
virtually no starting threshold. As a result, the hourly-averaged winds processed through
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AERMINUTE based on sonic data will not include any calm hours (defined as wind speeds
below the starting threshold of the anemometer).
The THRESH1MIN keyword specifies a threshold wind speed for the 1-minute ASOS
data. This threshold value only applies to the hourly averaged winds derived from the 1-minute
ASOS data and does not apply to the standard hourly NWS weather observations. Since the
minimum acceptable wind speed threshold for site-specific meteorological monitoring is 0.5 m/s
under current EPA guidance (EPA, 2000), users may specify the same threshold wind speed for
winds derived from 1-minute ASOS data.to avoid imposing a more stringent requirement on
data derived from 1-minute ASOS data than would he required lor a site-specific monitoring
program,
The THRESH1MIN keyword uses the following syntax
Syntax: THRESH_1MIN threshold speed
1
Type: Optional (Si;hjc 2 or Sichjc I and 2 com limed). Non-repeatable
where thresholdspeci! is the threshold wind speed in m s. If the user specifies a threshold
speed greater than n 5 m s. a warning is issued In AI-RMET. If a threshold wind speed greater
than I i) m s is specified. ALRMLT considers this a fatal error, will issue an error message, and
will not process data through Stage 2 The Stage 2 report file documents whether the
THRLSII l\ll\ option has been used
3.7.5 LOCATION
Past versions of AERMET required the LOCATION keyword under the METPREP
pathway in Stage 3. The METPREP LOCATION keyword had been used as the location for
determining the time of sunrise which is needed for convective mixing height calculations.
Beginning with version 11059, AERMET was modified to use the location of the primary
surface station (i.e., the ONSITE station or the NWS surface station) specified in Stage 1 to
determine the time of sunrise for mixing height calculations. The METPREP LOCATION
keyword is now only needed when site-specific mixing heights are provided during Stage 1 and
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upper air sounding data are omitted from the processing. Otherwise, a warning message will be
generated if the LOCATION keyword is included under the METPREP pathway, and the
LOCATION parameters will be ignored. For applications with only site-specific mixing
heights, without upper air data, the METPREP LOCATION keyword is needed for the
conversion from GMT to LST, since the time zone specified on the ONSITE pathway is likely
referenced to local time.
For those applications of AERMET when the MI-TPRN' I .OCATION keyword is
needed, it is identical in all respects to its usage on other pathways the site identifier, latitude
and longitude, and a time adjustment factor. The synui\ and type arc
Syntax:
LOCATION site id source lat/long source I0111* lai \tadjust]
Type:
Conditional (Stage 2 or combined Stage 1 and 2), Nonrepeatable
Order:
Latitude (lai) and longitude (long) can appear in either order
The site id is an eight-character alphanumeric specifier llial identi lies the site. This field is
simply a means to identify the site and is not used otherwise
The latitude (hit) and longitude (/oii^) 011 the MLTPRLP pathway should reflect the
location of the source, i.e . the location where the dispersion model is to be applied. Latitude
and longitude can he entered in either order because AERMET distinguishes between the two
by the suffix 011 each: a N or S with the latitude and W or E with the longitude. For example,
"38.4N 81.9W" would he interpreted the same as "81.9W 38.4N". AERMET cannot use, nor
does it recognize, " " orto discriminate between north and south and east and west.
The final parameter for this keyword, tadjust, is required and is an adjustment factor to
convert GMT to LST. The value of this parameter should be entered as a positive number for
sites west of Greenwich such as in the U.S.
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3.7.6 NWS HGT
When various parameters are computed for the dispersion models, the height of the
instruments is usually required. With site-specific meteorological data, the heights of the
measurements are generally available and entered through the READ or OSHEIGHTS
keywords on the ONSITE pathway in the Stage 1 control file. If there are no site-specific data,
or for isolated hours when there are site-specific data, then NWS data may be substituted for the
computations. However, instrument height is not one of llie reported parameters. The
NWS HGT keyword is used to provide this information The synliix and type are:
Syntax:
NWS HGT variable name instrument height
Type:
Mandatory, Repeat able
The variable name specifies which meteorological instrument is being referenced and is
followed by the instrument height in the appropriale units Currently, there is only one variable
name: WIND. Prior to the com ersion loASOS. the height of the wind instrument
(anemometer) was about 2" I eel ((> 7 meters) or 3<) leet I meters). The height of wind
instrumentation at ASOS sites is typically 33 leet (I'M meters) or 26 feet (7.9 meters). Annual
local climatolouical data are mailable from the NCI-1 and contain a historical record of
instrumentation sites and heights for the stations The user should consult a reference such as
the annual summaries prior to running Stage 2 to obtain the correct height to use with this
keyword. Al-RVTF.T requires the anemometer height in meters.
3.7.7 XDATi :s
Like all previous pathways, the amount of data processed can be limited by using the
XDATES keyword to specify the beginning and ending dates of the data to be merged. The
syntax and type are:
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XDATES YB/MB/DB [TO] YE/ME/DE
Syntax: Or
XDATES YB/MB/DB [-] YE/ME/DE
T # Optional (Stage 2 or Stage 1 and 2 combined),
Nonrepeatable
YB, MB and DB are the beginning year, month, and day, respectively, of the data to extract and
YE, ME, and DE are the ending year month and day, rcspccli\ civ Beginning with version
21DRF, the year must be entered as a four-digit integer (eg. 1l^2). The month is a one- or
two-digit integer corresponding to the month of the year and the day is the one- or two-digit day
of the month. The dates can be entered in various ways. The individual components of start
date or end date can be separated by spaces or the " " character or no separator at all. However,
the start date cannot be separated by spaces and the end dale separated by '/" or \ ice-versa.
Both dates must use the same delimiter. The complete start date and end date can be separated
by a space, '-', or the word "TO". The case of the word "TO" can be upper, lower, or a mix of
cases. The following are valid methods to enter the dates, using January 1, 2020 and December
31, 2020 as the dates:
2020/01/01 2<)2<) 12 I
2<)2<) "I "I TO 2<)2<) 12 I
2<)2<) "I "I 2< )2<) 12 I
2<)2<) i)| i)| TO 2020 12 31
2<)2<) "I "I 2<)2<) 12 3 I
2020 01 i)| 2<)2<) 12 31
20200101 20201231
The following are invalid methods to enter dates, again using January 1, 2020 and December 31,
2020 as the dates:
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2020/01/01 2020 12 31
2020 01 01 2020/12/31
2020/01/01 -2020 12 31
2020 01 01 -2020/12/31
2020/01/01 TO 2020 12 31
2020 01 01 TO 2020/12/31
The keyword is optional and if omitted, AERMI-T will determine the period of
extraction based on the dates present for input data (upper air. surface, site-specific, or
prognostic).
3.7.8 METHOD
The METHOD keyword is used lo define processing methods for the input data
including data substitution, special treatment olWSOS wind data, stable boundary layer
treatment, and upper air sounding selection. This MI-TI l()l) keyword requires a secondary
keyword {process) to identify the meteorological \ ariables that are affected and the option
(parameter) to use The syntax and type are
Syntax:
MI-TI l()l) process parai/ielcr
Type:
Optional (Stage 2 only Stage 1 and 2 combined),
RcpealaMe
The following is a list of \ alid secondary keywords that will be discussed in the
subsections that follow: WL\D_DIR, REFLEVEL, ASOS ADJ, UASELECT, STABLEBL,
CCVR, and TEMP.
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3.7.9 WIND DIR.
National Weather Service wind directions are reported to the nearest 10°. The secondary
keyword WINDDIR is used to enable and disable a randomization procedure which adjusts
NWS wind directions to yield directions to the nearest degree. The randomization procedure is
enabled or disabled by specifying RANDOM or NORAND, respectively, after the WIND_DIR
keyword. Prior to version 16216, randomization was disabled by default if the secondary
keyword WIND DIR was not specified. Beginning with \ eision I (>216, AERMET's default
behavior is to randomize NWS wind directions when the W IND I)[R keyword is not specified.
However, if the user wants a reminder as to how the data were processed, the RANDOM
parameter can be specified. WIND DIR is included in the METPRI- P pathway using the
following format:
Syntax:
Mi l l l()l) WTND DIR RANDOM
or
NOR WD
Type:
Optional (Stage 2 or Stage 1 and 2 combined),
Non-repeatable
Randomization is accomplished by using a single-digit random number, with a separate
random number predefined lor each hour of the year. This array of numbers is static and is the
EPA standard set of random numbers used to randomize wind directions. The random number
is added to the wind direction and 4 is subtracted from the result to yield a direction to the
nearest degree. The array of random numbers is internal to AERMET; therefore, a separate file
of these standard random numbers is not necessary.
This keyword has no effect when site-specific data are available for the hour. It is
assumed that the site-specific wind direction is reported to the nearest degree and does not need
randomizing.
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3.7.10 REFLEVEL
The secondary keyword REFLEVEL directs AERMET to substitute NWS data in the
computations in the event site-specific data are missing for the hour. The only valid parameter
is SUBNWS which enables data substitution to estimate boundary layer parameters. If there are
no site-specific data in the data base, i.e., only NWS hourly observations and upper air
soundings were merged, this secondary keyword REFLFYFF becomes mandatory, and if it is
omitted, AERMET detects this condition (i.e., no site-specific dala and do not substitute NWS
data) as an error and will not process any data. If there are site-specific data in the data base,
but some of the variables required for the boundary layer coni|")iilalions are missing, then this
parameter directs AERMET to SUBstitute MVS dala so the boundary layer parameters can be
calculated. Also, if the site-specific profiles of u i nd and 'or temperature are missing for an hour,
this parameter directs AERMET to use MVS dala to create a single-level profile of wind and/or
temperature. The format for enabling MVS substitution using the METHOD keyword in the
METPREP pathway is as follows:
Sy ill six: Mill IOI) RI I I. I \ I: I. SlIiNWS
r|, ^ Optional (Stage 2 or combined Stage 1 and 2),
*'H° Non-repeataMc
3.7.11 ASPS AD.I
Beginning with version I I "59, AERMET was been modified to add Vi knot (0.26 m/s) to
all ASOS-based wind speeds to compensate for the bias introduced due to the wind speeds being
truncated, rather than rounded, to whole knots (NOAA, 2008). There are two sources of ASOS
wind data that can be input to AERMET: 1) NWS data in one of the standard NWS surface data
formats; and 2) hourly-averaged wind speed and direction derived from 1-minute ASOS wind
data files generated with AERMINUTE (EPA, 2010).
The '/2 knot ASOS wind speed adjustment is applied, by default, during Stage 2
processing to wind speeds substituted from 1-minute ASOS wind data as well as those
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substituted from standard NWS/FAA surface data determined to be ASOS winds based on the
ASOS commission date. The user can override the default truncation adjustment by adding the
ASOSADJ method and NOADJ keyword to the Stage 2 METPREP pathway using the
following format:
Syntax: METHOD ASOS ADJ NO ADJ
T # Optional (Stage 2 or combined Stage 1 and 2),
Non-repeatable
To document the source of the wind data in the Stage 2 Ol TIM FT file output by
AERMET, and identify whether the wind speed was adjusted, a two-pan code is appended to
the end of each record. The first part of the code indicates whether the wind speed was or was
not adjusted with either "ADJ" or "NAD," respecli\ ely The source of the wind data for each
record is encoded as either "OS", "SIC". or "Al" to indicate the use of ONS1TE, PROG,
SURFACE, or 1-minute ASOS winds, rcspecli\ ely The two pails of the code are separated by
a hyphen, and if no wind data are available lor a particular hour, the second part of the code is
blank.
3.7.12 st \m.i:m.
AI-RMI-T includes two options for stable boundary layer conditions, a Bulk Richardson
Number approach to calculate ir and u* and an approach to adjust u* under low wind stable
conditions. Each is detailed below
3.7.12.1 BULKRN
AERMET includes an option to calculate u* and 9* using a Bulk Richardson Number
approach using temperature differences between two heights for site-specific data using the
METHOD STABLEBL BULKRN keyword on the METPREP pathway in the Stage 2 input file.
To use the BULKRN approach, the temperature differences between the two heights are
included in the site-specific data using the DT01 variable in the Stage 1 inputs for ONSITE or
PROG pathway. Additionally, the two heights for the temperature differences are listed with
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the DELTATEMP keyword in the Stage 1 input file with the ONSITE or PROG pathway. See
Section 3.5.11 for more information about the temperature differences input to AERMET. The
syntax for the BULKRN option is:
Syntax:
METHOD STABLEBL BULKRN
Type:
Optional (Stage 2 or combined Stage 1 and 2), Non-repeatable
3.7.12.2 ADJ U*
AERMET includes an option in Stage 2 processing to adjust the surface friction velocity
(u* or ustar) for low wind speed stable conditions, based on ()iun and Venkalram (2011). The
option is selected by including the MI-TI l()l) STAIJLEBI. Al).l U* keyword on the METPREP
pathway in the Stage 2 input file. In addition. Al- RMI-T incorporated a new ADJU* option for
applications that utilize the Bulk Richardson Number (lil I ,KR\) option for estimating the
stable boundary layer ir using lo\\-le\ el temperature difference (delta-T) data based on Luhar
and Rayner (2009)) The syntax of the AD.I I * option is as follows:
Sy ill six:
mitiiod ST\m.i:m. adj u*
1
Type:
Optional (Stage 2 or combined Stage 1 and 2), Non-repeatable
There are ca\ eats with use of the ADJU* in AERMET. AERMET will perform the
adjust u* calculations regardless of the presence of turbulence variables in the input data.
However, as outlined in Appendix W (40 CFR Part 51), the use of adjusted u* is prohibited
when site-specific turbulence is input to AERMOD as well when AERMOD is run in
DEFAULT mode. AERMOD will issue an error and abort. The ADJ U* option is considered a
non-Default option in AERMOD when site-specific data that include turbulence are included.
There are options in AERMOD (added with version 21112) to allow the user to use
meteorological data that uses the ADJ U* option even if turbulence data are included in the
AERMOD inputs. There are options in AERMOD that essentially ignore the input turbulence
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parameters. See the AERMOD User's Guide Section 3.5.9 for details (EPA, 2021b). The use of
ADJU* and turbulence is subject to the alternative model provisions in Section 3.2 of
Appendix W (40 CFR Part 51). Users should coordinate with the appropriate reviewing
authority regarding the procedures and requirements for approval of using ADJ U* and
turbulence for regulatory modeling applications.
3.7.13 CCVR and TEMP
Beginning with version 13350, the AERMET program includes substitutions for missing
cloud cover and temperature data based on linear interpolation across gaps of one or two hours.
Linear interpolation across short gaps is a reasonable approach for these \ ariables since ambient
temperatures tend to follow a diurnal cycle and do not vary significant I \ from hour to hour, and
AERMOD is relatively insensitive to hourly fluctuations in cloud cover, especially during
convective hours since the heat flux is integrated across the day Furthermore, gaps of one or
two hours for these parameters near the early morning transition to a convective boundary layer
may result in all com ecti\ e hours for that day being missing
The cloud co\ er and temperature substitutions are applied In default unless the
application involves both WVS and ONSITF. surface data. Substitutions will be applied by
default if the parameter is only a\ ailaMe lor one type of data (NWS or ONSITE). For example,
for cases with ONSITE data that includes temperature data but no cloud cover data, the cloud
cover substitutions will be applied to the NWS data by default, but the temperature substitutions
will not be applied unless the user specifies the TEMP SUB TT option on the METHOD
keyword in Stage 2 Options ha\ e also been incorporated in AERMET during Stage 2 that
allow users to disable cloud co\ er and/or temperature substitutions, irrespective of the type(s) of
data being processed. These Stage 2 options also allow users to activate these substitutions for
cases with both NWS and ONSITE data; however, this could result in substitutions based on
interpolation between NWS and ONSITE values on either side of the gap.
As noted above, the substitutions are based on linear interpolation across gaps of one to
two hours. Interpolations are only made based on non-interpolated values on both sides of the
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data gap. In addition, substitutions for missing ONSITE temperature data are only applied for
values from the same measurement level, if multi-level temperature data are available.
The options for users to disable or activate the cloud cover (CCVR) and temperature
(TEMP) substitutions are included under the METHOD keyword in Stage 2. Unlike previous
versions of AERMET, version 21DRF can interpolate temperatures for hours 23 and 24 as
version 21DRF uses internal arrays so AERMET can "read ahead" for substitution. For this
reason, persistence is not used and the NOPERS option (no persistence) in previous versions of
AERMET is obsolete and is ignored by AERMET.
Syntax: METHOD CCVR SUBCC (activates CCVR substitutions)
or
METHOD CCVR XO SUB (disables CCVR substitutions)
METHOD TEMP SI Ii I T (aeti\ ales IT.MP substitutions)
or
MI'TIIOI) TI-VTP "NOTSl'IJ (disables Tl-VIP substitutions)
1
Type: Optional (Stage 2 only or Stage I and 2 combined), Non-repeatable
(lor a gi\ en option of CCVR of TEMP)
3.7.14 Sl NRISi:
The AERMET meteorological preprocessor was originally developed to work with NWS
upper air sounding data available in the United States and North America. Since that time,
AERMET has been increasingly applied in areas outside North America. If observed ONSITE
mixing heights are not available, AERMET requires a morning sounding to compute the hourly
convective mixing heights for AERMOD. The preferred sounding time is prior to sunrise,
before the convective mixed layer begins to develop. In North America, this generally means
the 1200 GMT sounding (also referred to as the 12Z sounding). In other parts of the world this
means the 0000 GMT (or 00Z) sounding. Originally, AERMET was designed to automatically
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select the 12Z sounding, consistent with the primary focus of the AERMOD model development
to support modeling applications within the U.S. Since the reported upper air observation time
is known to vary slightly, AERMET also defined a default "sounding window" of ±1 hour, i.e.,
AERMET accepted the 11Z, 12Z, or 13Z sounding. Beginning with version 11059, AERMET
was enhanced to select an upper air sounding that is more appropriate for the location where
AERMET is being applied.
The world is divided into 24 time zones, but most /ones do not follow a straight north-
south line of longitude (see Figure 3-1). As a result, the lime zone adjustment parameter on the
LOCATION keyword on the Stage 1 UPPER.\IR pathway is not a reliable indicator for
selecting the appropriate sounding time. Beginning with version 11
-------
Hau*i.
Sudan
+9'/z
Australia
2004 F.
www.fgLenr .com
Figure 3-1. Time Zone Boundaries (with preferred sounding time across top).
Time Zone
-12
-10
-9
-7
-6
-4
-2
-1
Sounding
-12
12
12
12
12
12
12
12
12
00
00
00
00
Time Zone
10
11
12
Sounding
00
00
00
00
00
00
00
-12
-12
-12
-12
-12
Figure
-2. Preferred sounding time
jy time zone.
AERMET has also been enhanced to include an optional method to search for the
morning sounding based on the local time of sunrise at the UPPER AIR station location. Using
the new method, SUNRISE, AERMET can search for the sounding nearest to sunrise rather than
looking for a 00Z or 12Z sounding. By default, when this option is specified, AERMET
attempts to find a sounding within 6 hours before sunrise, and if that search fails, it searches up
to 2 hours after sunrise. This search window, as well as the default search window when the
SUNRISE method is not enabled, can be extended in either direction using the new keyword
UAWINDOW, described below in Section 3.7.15. When search for a sounding using the
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SUNRISE method, priority is given to soundings prior to and including sunrise, such that a
sounding that is 4 hours before sunrise is preferred, and selected, over a sounding that is 1 hour
after sunrise.
To invoke this search, a new option for the METHOD keyword under the METPREP
pathway in Stage 2 has been defined: UASELECT. The syntax of the new UASELECT option
is as follows:
Syntax: METHOD UASELECT SUNRISdi)
1
Type: Optional (Stage 2 only or Stage I and 2 combined). Xon-repeatable
Note that the 'E' on 'SUNRISE' is optional and can be omitted
3.7.15 UAWINDOW
By default, AI-RMI-T uses a I-hour window before and afler the preferred sounding
time as the search window lo locale a sounding to use Beginning with version 11059, the user
can expand (or contract) this window by using the optional UAWINDOW key word under the
METPREP pathway in Stage 2 The syntax of the I WVINDOW keyword is as follows:
Syntax: I WVINDOW window begin window end
1
Type: Optional (Stage 2 only or Stage 1 and 2 combined), Non-repeatable
where window begin represents the beginning of the sounding window and window end
represents the end of the sounding window, entered as the number of hours relative to the
preferred sounding time (whether it be 12Z or 00Z). A negative number indicates the number of
hours before the reference sounding, and a positive number indicates the number of hours after
the sounding. The default sounding window would be input as: UAWINDOW -1 +1 (note that
the plus sign in not required). The sounding window does not have to be symmetric about the
sounding time. For example, if the user wants to search more hours before the sounding time
and fewer after, the following could be used: UAWINDOW -5 +2. To force AERMET to
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accept only soundings corresponding to the reference sounding time, the user would input:
UAWINDOW 0 0. If multiple soundings are available within the upper air sounding window,
AERMET will select the sounding closest in time to the reference sounding, with a preference
for soundings prior to and including the reference sounding time. For example, if
UAWINDOW -5 +2 is specified, and soundings are available for 9Z, 12Z, and 15Z, AERMET
would select the 12Z sounding. However, if soundings were available for 9Z and 13Z,
AERMET would select the 9Z sounding.
As with the 12Z/00Z sounding search, the user can expand or contract the search
window for the SUNRISE option (-6 to +2 hours In delimit) using the UAWINDOW keyword.
The syntax for the UAWINDOW keyword is the same in both cases When used UAWINDOW
is used in conjunction with the SUNRISE method, wimlou begin and wnn/ou end represent
the number of hours before and after sunrise to conduct the search. For purposes of applying
the sounding window, sunrise is defined as the beginning of the hour during which the sun rises.
For example, if sunrise is calculated to occur at no 45 local lime. AERMET will define sunrise
as 0600 and preference u ill be gi\ en lo a sounding al (Hiiio \ s a sounding at 0700.
3.7.16 Surface characteristics
Surface conditions at the measurement site, referred to as the surface characteristics,
influence boundary layer parameter estimates. Obstacles to the wind flow, the amount of
moisture at the surface, and rcllccli\ ity of the surface all affect the estimates. These influences
are quantified through the surface albedo, Bowen ratio and roughness length (z0). Beginning
with version 21DRI'. AI-RMI-T allows for the input of hourly surface characteristics for
overwater applications for the PROG pathway. For all other applications, the surface
characteristics are input via the methods described below. For overwater applications with the
PROG pathway, the surface characteristics input methods described below are used to fill in
missing values for the hourly surface characteristics.
AERMET requires two sets of surface characteristics (primary and secondary) in the
METPREP pathway of the Stage 2 control file when the SUBNWS option is specified and both
ONSITE and SURFACE data are provided (including 1-minute ASOS wind data). If either
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ONSITE (PROG) data or SURFACE data are omitted, only a single (primary) set of surface
characteristics is required.
The primary set of surface characteristics are defined for AERMET through the three
keywords FREQSECT, SECTOR and SITE CHAR used to specify the temporal frequency,
number of sectors, and the site characteristics (albedo, Bowen ratio, and effective surface
roughness length), respectively. The secondary set of si Ic characteristics are specified using
similar keywords, FREQSECT2, SECTOR2, and SIT1- CI IAR2 These keywords for the
secondary set should be added to the METPREP pathway immediately after the primary set of
characteristics when defining both a primary and secondary set (if surface characteristics. For
the primary set of characteristics, the FREQ SI.CT keyword must appear before SECTOR and
SITE CHAR keywords. The same is true for the secondary set of characteristics.
FREQ SECT2 must appear before the SECTOR2 and SITI- CI IAR2 keywords. The keywords
for the primary characteristics should be grouped together and the secondary characteristics
should be grouped together. Each keyword is detailed below
3.7.16.1 Frequency and number of sectors I 'RI -Q SI X T or I Kl -Q SECT2
The FREQ SI X T and IRIX.) SI XT2 keywords define how often the surface
characteristics change (theJrct/nciicy). or alternate ely. the period over which these
characteristics remain constant, and the number of non-overlapping sectors into which the 360°-
compass is di\ided (number <>J sectors).
The syntax and type lor the FREQ SECT and FREQ SECT2 keywords are as follows:
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FREQ SECT frequency number of sectors [year list]
Syntax:
or
FREQ SECT2 frequency number of sectors [year list]
Type:
Mandatory (Stage 2 or Stage 1 and 2 combined), Nonrepeatable (if no
years listed), Repeatable (if years listed), Reprocessed
Order:
These keywords must appear before SECTOR (SECTOR2) and
SITE CHAR (SITE CHAR2)
The frequency can be ANNUAL, SEASONAL or MONTI ILY, corresponding to 1, 4, or
12 periods, respectively. ANNUAL and MONTHLY arc straightforward: the site characteristics
are the same for all months of the year, or the site characteristics \ arv from month to month,
respectively. When SEASONAL is specified, then the site characteristics arc distributed by
month as follows for the northern hemisphere.
Season # Season Months
1 Winter December. January. Lebruary
2 Spring March. April. May
3 Summer June. July. August
4 Autumn September, October, November
For the southern hemisphere the site characteristics are distributed by month as follows:
Season Season Months
1 W inter June, July, August
2 Spring September, October, November
3 Summer December, January, February
4 Autumn March, April, May
When entering the surface characteristics by season, AERMET will use the location of the
primary and secondary site to determine the hemisphere of the site and assign the seasonal
characteristics to the correct months. For example, for a location in the southern hemisphere,
the user does not have to assign summer surface characteristics to winter in AERMET to
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account for the fact that AERMET previously use northern hemisphere month to season
assignments (i.e., June-August as spring). The user now enters summer surface characteristics
to summer and AERMET will assign the correct months, June-August for the northern
hemisphere, and January, February, and December, for the correct summer assignments.
The number before the season represents the frequency-index that is specified for that season on
the SITECFLAR keyword. Beginning with version 21DRF. AERMET will use the coordinates
listed for the primary and secondary surface characteristics sites to determine the hemisphere-
seasonal assignments.
A minimum of 1 and a maximum of 12 can he specified for the number of sectors.
Beginning with version 21DRF, the user has the option to list which year or years go with a
specific set of surface characteristics if performing a multi-year run of AERMI-T with the
optional year list. This is to allow the user to calculate boundary layer parameters for multiple
years without running AERMET for each year separately if surface characteristics change year
by year. For a more detailed description and example, see Section 3.7.16.5. The year list can a
single year, a list of years separated by commas or spaces, or a range of years, i.e., 2010-2015.
3.7.16.2 Defining sectors SECTOR or SECT()R2
A SI X TOR statement defines the beginning and ending wind direction sector for which
the surface characteristics apply The syntax and type of this keyword are:
SI .CTOR sector index beginning direction ending direction
Syntax:
or
S1.( T()R2 sector index beginning direction ending direction
SECTOR: Mandatory, SECTOR2: Conditional
Type:
(Stage 3), Repeatable, Reprocessed
One sector is defined per keyword, with the sector index linking a specific sector to a
set of site characteristics. The sectors are defined clockwise, they must cover the full circle, and
these must be defined so that the end of one sector corresponds to the beginning of another. The
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beginning direction is considered part of the sector, while the ending direction is excluded
from the sector. The directions reference the direction from which the wind is blowing. A
sector can cross through north (e.g., 345 - 15) or can start and stop at north (e.g., 0-30 and
270 - 360). AERMET will verify that the entire 360° circle is covered. See Section 5.6.2.1 for
additional discussion about sectors.
3.7.16.3 Specification of surface characteristics: SITE CTTAR or SITE CHAR2
The site characteristics are specified on the SI IE CII AR and SITECHAR2 keywords,
with one statement for each combination of period and wind sector. The syntax and type for
these keywords are:
SITECHAR
Syntax: or frequency index sector index albedo Bowen roughness
SITECHAR2
Type: Mandatory(Stage 2). RepcalaMe. Reprocessed
The frequency index \ aries from one to the number of time periods corresponding to the
frequency defined on the I'RI-O SI X T (or I'RI-O SI X T2) keyword. The sector index varies
from one to the number of sectors defined on the I 'RI-O SECT (or FREQ SECT2) keyword.
These indices are followed by the albedo, Bowen ratio and roughness length for the
frequency sector combination 11" the maximum frequency (MONTHLY) and maximum number
of sectors were defined (12). then it would require 144 (12 frequencies and 12 sectors)
SITE CHAR (or SITI- CI IAR2) statements to completely define the site characteristics.
The albedo is the fraction of total incident solar radiation reflected by the surface back to
space without absorption. Typical values range from 0.1 for thick deciduous forests to 0.90 for
fresh snow. The daytime Bowen ratio, an indicator of surface moisture, is the ratio of the
sensible heat flux to the latent heat flux and is used for determining planetary boundary layer
parameters for convective conditions. While the diurnal variation of the Bowen ratio may be
significant, the Bowen ratio usually attains a fairly constant value during the day. Midday
values of the Bowen ratio range from 0.1 over water to 10.0 over desert. The surface roughness
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length is related to the height of obstacles to the wind flow and is, in principle, the height at
which the mean horizontal wind speed is zero. Values range from less than 0.001 m over a calm
water surface to 1 m or more over a forest or urban area.
Table 3-1 through Table 3-5Table 3-5, from Paine (1987), provide some guidance on
specifying these values by land use type and season. In these tables, the seasons do not
correspond to a particular group of months, but more on latitude and the annual vegetative
growth cycles. Spring refers to the period when vegetation is emerging or partially green and
applies to the 1-2 months after the last killing frost. The tu rn summer applies to the period
when vegetation is lush. The term autumn refers to the period of the year when freezing
conditions are common, deciduous trees are leafless, soils are bare after harvest, grasses are
brown, and no snow is present. Winter conditions apply to snow-covered surfaces and
subfreezing temperatures. For example. March in the southern I nited States is spring, but it is
still winter in much of New England It is up to the user to determine how to apply this
information.
Table 3-1. Albedo of (.round Covers hy Land Use and Season
Land-Use
Spriim
Summer
Autumn
Winter
Water (fresh and sea)
0.12
0.10
0.14
0.20
Deciduous I'orest
0.12
0.12
0.12
0.50
Coniferous I'orest
0.12
0.12
0.12
0.35
Swamp
0.12
0.14
0.16
0.30
Cultivated Land
0.14
0.20
0.18
0.60
Grassland
0.18
0.18
0.20
0.60
Urban
0.14
0.16
0.18
0.35
Desert Shrubland
0.30
0.28
0.28
0.45
The Bowen ratio for winter in the next three tables depends on whether a snow cover is
present continuously, intermittently, or seldom. For seldom snow cover, the values between
autumn and winter may be more applicable; for continuous snow cover, the values for winter are
applicable. For bodies of water, it is assumed that the surface is frozen.
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Table 3-2. Daytime Bowen Ratio by Land Use and Season - Dry Conditions
Land-Use
Spring
Summer
Autumn
Winter
Water (fresh and sea)
0.1
0.1
0.1
2.0
Deciduous Forest
1.5
0.6
2.0
2.0
Coniferous Forest
1.5
0.6
1.5
2.0
Swamp
0.2
0.2
0.2
2.0
Cultivated Land
1.0
1.5
2.0
2.0
Grassland
1.0
2.0
2.0
2.0
Urban
2.0
4 i)
4.0
2.0
Desert Shrubland
5.0
6.0
| D.I)
10.0
Table 3-3. Daytime Bowen Ration by Land Use and Season - Average Moisture
Conditions
Land-Use
Spring
Summer
Autumn
Winter
Water (fresh and sea)
i) 1
0.1
0.1
1.5
Deciduous Forest
0.7
0.3
1.0
1.5
Coniferous Forest
0.7
0.3
0.8
1.5
Swamp
0.1
0.1
0.1
1.5
Culli\tiled l.tind
0.3
0 5
0.7
1.5
Grassland
0.4
0.8
1.0
1.5
Urban
1.0
2.0
2.0
1.5
Desert ShruMand
3.0
4.0
6.0
6.0
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Table 3-4. Daytime Bowen Ratio by Land Use and Season - Wet Conditions
Land-Use
Spring
Summer
Autumn
Winter
Water (fresh and sea)
0.1
0.1
0.1
0.3
Deciduous Forest
0.3
0.2
0.4
0.5
Coniferous Forest
0.3
0.2
0.3
0.3
Swamp
0.1
0.1
0.1
0.5
Cultivated Land
0.2
0.3
0.4
0.5
Grassland
0.3
0.4
0.5
0.5
Urban
0.5
1 i)
1.0
0.5
Desert Shrubland
1.0
1.5
2.0
2.0
Table 3-5. Surface Roughness Length, in Meters, by Land I se and Season
Land-Use
Spring
Slimmer
Autumn
Winter
Water (fresh and sea)
1) DDI) |
1) DDI) |
0.0001
0.0001
Deciduous Forest
1.00
1.30
0.80
0.50
Coniferous Forest
1.30
1.30
1.30
1.30
Swamp
0.20
0.20
0.20
0.05
Cultivated T.and
0.03
0.20
0.05
0.01
Grassland
0.05
0.10
0.01
0.001
I rhan
1 DO
| do
1.00
1.00
Desert SliruMand
0.30
0.30
0.30
0.15
An additional source of information for surface roughness length can be found in Stull
(1988). Surface characteristics used in AERSURFACE may be more appropriate than those
shown above and can be found in the AERSURFACE User's Manual (EPA, 2020).
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3.7.16.4 Optional keywords AERSURF and AERSURF2
AERMET includes optional keywords, AERSURF and AERSURF2 under the
METPREP pathway, which can be used to specify separate external files which contain the
necessary AERMET keyword inputs to specify surface characteristics for the primary and
secondary site, respectively. These keywords facilitate the use of surface characteristics based
on the AERSURF ACE tool (EPA, 2020), without the requiring the user to copy-and-paste the
results into the AERMET input file. The syntax of the new AI-RSURF and AERSURF2
keywords is as follows:
AERSURF primary smlcharjdename \year list \
Syntax:
AERSURF2 secondary snrjeharfilename [year hsi\
1
Type: Optional, Non-repeatable
where primary surfcharfilename and secondary surfchar Ji/eiiame refer to the names of the
files containing the surface characteristics lor the primary and secondary sites, respectively and
year list refers to the list of yours as described in Section 3 7 I (-> I
Note that surface characteristics included in an AERSURF file are interpreted by
AERMI-T to he for the primary surface ohser\ ation site, and setup errors will occur if keywords
for the secondary surface characteristics site (FREQSECT2, SECTOR2, or SITE CHAR2) are
encountered On the other hand, data included in the AERSURF2 file are interpreted by
AERMET to he for the secondary site and will be processed as if the FREQ SECT2,
SECTOR2, and SITI- CI IAR2 keywords were used, even if the primary site keywords are
specified. This allows for the use of an AERSURF ACE output file for the AERSURF2
keyword without requiring the user to edit the AERSURF ACE file to modify the keywords.
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3.7.16.5 Optional yearly assignment of surface characteristics
As discussed in Section 3.7.16.1 the user can assign specific surface characteristics to
each year in a multi-year AERMET run. The year assignment can also be done for an
AERMET run that is for a single run. The addition of this assignment in AERMET is to allow
the user to execute one AERMET run for a multi-year AERMET dataset versus running each
year separately in Stage 2 (old Stage 3). For example, prior lo \ ersion 21DRF, if processing
AERMET for a 5-year dataset and year 1 was a dry year and year 2 was wet, or year 3 had a
change in number of sectors than other years, then Stage 3 would have to be processed
separately for each year and then the resulting outputs had to lx- concatenated together to create
a single meteorological dataset for input to AI-RMOI). Beginning with \ ersion 21DRF, the user
can enter a set of surface characteristics and assign to one or more years of the processed period.
To invoke the multi-year capability in AERMET, the user enters the years assigned to the
specific set of surface characteristics after the number of sectors associated with the site with the
FREQSECT or FREQSECT2 keyword The use of a year list is independent for
FREQSECT and FRF.Q SF.CT2 if hotli are specified That is to say, the user can specify
multiple surface characteristics for the primary site hut use constant set of surface characteristics
for all years for the secondary site A ca\ eat to using a year list is that all years in the AERMET
run be accounted for in the lists If multiple surface characteristics are used for a site, then each
year must be accounted for in the list(s)
The following show s the formal for defining both a primary and a secondary set of
surface characteristics in the MI-TI'REP pathway for a period from 2016-2020. All years have
the same number of sectors hut 2D 1.6, 2018, and 2019 are dry years for the primary site, and
2017 and 2020 are average moisture conditions for the primary site. For the secondary site,
2016, 2017, and 2020 are wet years and 2018 is a dry year and 2019 is an average year. The
format would be:
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** Primary Surface Characteristics, 2016, 2018, 2019
FREQ_SECT frequency number_of_sectors 2016 2018 2019
SECTOR sector_index beginning_direction ending_direction
SITE_CHAR frequency_index sector_index albedo Bowen roughness
** Primary Surface Characteristics, 2017 and 2020
FREQ_SECT frequency number_of_sectors 2017 2020
SECTOR sector_index beginning_direction ending_direction
SITE_CHAR frequency_index sector_index albedo Bowen roughness
** Secondary Surface Characteristics, 2016, 2017, and 2020
FREQ_SECT2 frequency number_of_sectors 2016 2017 2020
SECTOR2 sector_index beginning_direction ending_direction
SITE_CHAR2 frequency_index sector_index albedo Bowen roughness
** Secondary Surface Characteristics, 2018
FREQ_SECT2 frequency number_of_sectors 2018
SECTOR2 sector_index beginning_direction ending_direction
SITE_CHAR2 frequency_index sector_index albedo Bowen roughness
** Secondary Surface Characteristics, 2019
FREQ_SECT2 frequency number_of_sectors 2019
SECTOR2 sector_index beginning_direction ending_direction
SITE CHAR2 frequency index sector index albedo Bowen roughness
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Using the AERSURF and AERSURF2 keywords the format would be:
** Primary Surface Characteristics, 2016, 2018, 2019
AERSURF filenamel 2016 2018 2019
** Primary Surface Characteristics, 2017 and 2020
AERSURF filenamel 2017 2020
** Secondary Surface Characteristics, 2016, 2017, and 2020
AERSURF2 filename2 2016 2017 2020
** Secondary Surface Characteristics, 2018
AERSURF2 filename2 2018
** Secondary Surface Characteristics, 2019
AERSURF2 filename2 2019
The primary set of characteristics will he applied lor those hours in which the data are
used when the data are pro\ ided. I .ikewise. the primary characteristics will be applied to the
NWS surface data if site-specific data are omitted from the application and only one set of
surface characteristics is required If both site-specific data and NWS surface data (including 1-
minute ASOS) are pro\ ided. along with the SUBNWS option to allow substitution of NWS
surface data for missing onsite wind and temperature data, the primary surface characteristics
will be applied to the site-specific data for those hours in which site-specific wind data are used,
and the effecti \ e surface roughness from the secondary set will be applied for those hours in
which wind data from the NWS surface file or 1-minute ASOS wind data file are substituted for
missing or calm onsite data. Note: The albedo and Bowen ratio from the primary set of
surface characteristics are always applied regardless of whether ONSITE or SURFACE
data are used for a given hour. The albedo and Bowen ratio from the secondary set are
not used at this time, but values must be included to maintain consistency in the formats
for reading the data.
3-75
-------
3.8 Output from Stage 2: OUTPUT and PROFILE
AERMET Stage 2 processing creates two output files for the AERMOD dispersion
model. The first of these files contains the boundary layer parameters and some of the data that
went into computing these parameters. These parameters are stored in the file defined on the
OUTPUT keyword, with the following syntax and type:
Syntax:
OUTPUT parameter filename
Type:
Mandatory (Stage 2 only or Stage 1 and 2 combined),
Nonrepeatable
The parameterJilename must conform to the naming conventions appropriate to the computing
platform. The maximum length of this file name is characters
There is one record for each hour processed These data are written with at least one
space between each element, i.e., "free formal" The exact formal ol'this file is in Error!
Reference source not found. The contents ol'this 11 le arc
Year
Month (I - 12)
Julian Day (I - 3 (¦>(¦>)
I lour (1 - 24)
Sensible heatfluv 11 (Watts/meter2)
Surface friction \ elocity, u* (meters/second)
Convective velocity scale, w* (meters/second)
Vertical potential temperature gradient in the 500 m layer above the planetary
boundary layer (kelvin/meter)
Convective mixing height, z,c (meters)
Mechanical mixing height, zim (meters)
Monin-Obukhov length, L (meters)
3-76
-------
Surface roughness length, z0 (meters)
Bowen ratio, B0
Albedo, r ($)
Wind speed - used in estimating the boundary layer parameters (meters/second)
Wind direction - direction wind is blowing from (degrees)
Height at which the wind was measured (meters)
Temperature - used in estimating boundary I aver parameters (kelvin)
Height at which the temperature w as measured (meters)
Precipitation type code (0=none. I I liquid, 22=frozen. missing)
Precipitation amount (millimeters/hour)
Relative humidity (%)
Station pressure (milliba i s)
Cloud co\ er (lentils)
Wind speed adjustment Hag for adjustment of ASOS wind speed data
(AD.T adjust. NAD not adjusted. l,KOG=prognostic data)
Wind data source llau (OS ()\SITI- pathway input file, SFC = SURFACE
pathway input file)
Substitution llau (NoSubs No substitution, Sub CC = substituted cloud cover,
Sub I T substituted temperature, Sub_CC-TT = substituted cloud cover and
temperature)
A second file is u ritten during Stage 2 - a file of profile (multilevel) data as identified on
the PROFILE keyword. The syntax and type are:
3-77
-------
Syntax:
PROFILE profile filename
Type:
Mandatory (Stage 2 only or Stage 1 and 2
combined), Nonrepeatable
The profile Jilename must conform to the naming conventions appropriate to the computing
platform. The maximum length of this file name is 96 characters.
There are one or more records for each hour processed The data are written with at least
one space between each element, i.e., the data are free formal The exact format of this file is in
Error! Reference source not found.. The contents of lliis file are
Year
Month (1 - 12)
Day (1-31)
Hour (1 - 24)
Measurement height (meters)
Topflag I. if this is the last (highest) level for this hour
fi otherwise
I )i recti on the wind is blowing from lor the current level (degrees)
Wind speed for the aiiTenl level (meters/second)
Temperature at the current level (degrees Celsius)
Standard de\ iation of the wind direction fluctuations, oe (degrees)
Standard de\ iation of the vertical wind speed fluctuations, o (meters/second)
The data in this latter file are the multilevel (e.g., tower) site-specific meteorological data
if site-specific data are available. If there are no data for a particular variable for an hour, either
at one or all levels, then the field is filled with a missing value indicator. Only the variables
listed above are in this output file. Additional variables that may be specified on the ONSITE
pathway (e.g., the standard deviation of one of the horizontal components of wind) are not
written to this file.
3-78
-------
AERMET was designed to be able to perform these dispersion parameter calculations
with NWS data only, i.e., no site-specific data. In this case, the NWS winds and temperature are
used to create a one-level "profile". The NWS data are also used if all the variables at all levels
for a given hour are missing. However, this substitution depends on the specification of the
METHOD REFLEVEL keyword described in Section 0.
3-79
-------
4.0 Example AI RM IT runs
Following are two examples of an AERMET ran from start to finish. The first example
is a case that is the most often used for AERMET and AERMOD applications, National
Weather Service data for the surface data and upper air data. The second example builds upon
the first in that the NWS example is used in conjunction with site-specific data. Each example
will show each stage's input and output along with the message and report files. For the
purposes of showing how AERMET functions, each data source will be its own AERMET stage
1 run.
4.1 National Weather Service data
4.1.1 Surface data extraction
The first example is to extract and OA National W eather Service surface data for
Albany, NY for a ten-day period of March I through March 10. NS8. Figure 4-1 shows the
stage 1 control file, EXOI SI Rl ACE.INP The raw surface data are CD-144 format and
extracted and QA data will lx- written to SURI ACE EXTRACT.TXT and
SURFACE OAOl T TXT respecti\ ely Note that lor QA, no additional variables are requested
for auditing so auditing will he limited to winds and temperature. The report file and message
files are EX<)I SI SI RI ACE REI'ORT.TXT and EX01_S1_SURFACE_MESSAGE.TXT
respecth ely Note that filenames do not have to have ".txt" extension, but for the purposes of
the example. " l\l" extensions are used for easier opening in a text editor.
4-1
-------
JOB
REPORT
MESSAGES
EX01 SI SURFACE REPORT.TXT
EX01 SI SURFACE MESSAGE.TXT
SURFACE
DATA
EXTRACT
QAOUT
S1473588.144 CD144 1
SURFACE EXTRACT.TXT
SURFACE QAOUT.TXT
XDATES
1988/3/1 TO 1988/3/10
LOCATION
14735 42.75N 73.8W 0
** 725180 14735 ALBANY COUNTY AP
US US NY KALB
t-42750 -073800 +00838
Figure 4-1. Control file to extract and QA NWS surface data.
To execute AERMET stage 1 for this example, the user would type the following at the
command prompt:
aermet.exeEXOl SL RI ACi: l\l»
assuming the control 11 le and AI-RMI-T executable are in the same folder. Processing
information will be written to the screen If the user w ishes to have that information written to a
text file, the user would type the following at the command prompt:
aermet e\e l-.\<)| SI Rl ACIs.INP > example_run.txt
The contents of example run.txt are shown in Figure 4-2 and show the AERMET
processing. The lust line lists the start date and time of the AERMET processing. The next ten
lines notify the user of the extraction dates followed by ten lines denoting each day's data are
being QA'd. The final messages are that AERMET completed successfully followed by the
AERMET processing end date and time.
4-2
-------
START PROCESSING DATE/TIME: NOVEMBER 08, 2021 11:31:02 AM
Stage 1: Extracting surface data for month/day /year 03/01/1988 LST
Stage 1: Extracting surface data for month/day/year 03/02/1988 LST
Stage 1: Extracting surface data for month/day/year 03/03/1988 LST
Stage 1: Extracting surface data for month/day/year 03/04/1988 LST
Stage 1: Extracting surface data for month/day/year 03/05/1988 LST
Stage 1: Extracting surface data for month/day/year 03/06/1988 I.ST
Stage 1: Extracting surface data for month/day/year 03/07/198S I.ST
Stage 1: Extracting surface data for month/day/year 03/ns |<)8X I.ST
Stage 1: Extracting surface data for month/day/year O Vi i<) | <)S8 LST
Stage 1: Extracting surface data for month/day/year O ^ I (i I ''88 LST
Stage 1: QA'ing surface data for month/day/year 03/111 I 'JNN LST
Stage 1: QA'ing surface data for month/day/year 03/02/1988 I.ST
Stage 1: QA'ing surface data for month/da> >caru i 03/1988 I.ST
Stage 1: QA'ing surface data for month/da> >caru i u4 I ''88 LST
Stage 1: QA'ing surface dala fur iikmih da> >eai'(ii <>5 I'JSS I.ST
Stage 1: QA'ing surface dala fur mniiili da> >caru i o<. |<)XX I.ST
Stage 1: QA'ing surface dala fur mniiili da> >caru i u" |<)XX I.ST
Stage 1: QA'ing surface dala fur nioiiih da> >caru i ox I'JXX I.ST
Stage 1: QA'ing surface dala fur moiiili da> >eai'(ii u<) |<)XX I.ST
Stage I Q Vim: surface dala lor moiiili da> \eai't>i |n |»jxx I.S'I'
ALRMI I I l\ISI ILI) SI ( ( I SSI I I I^
ENDPROCESSI\(i I) VI'E/TIMi: \( )VEMBER 08, 2021 11:31:02 AM
Figure 4-2. 1'roccssiii" slcps for NWS surface data extraction.
Figure 4-3 shows the processing messages contained in
EX01_S1_SURFACE_MESSAGE.TXT. Messages that start with 'W' are warning messages,
T are informational messages, 'E' are error messages and 'Q' are quality assurance messages.
Refer to Appendix D for message definitions. The very first message is a warning message
indicating that too many fields were found with the DATA keyword and that the blocking factor
or type was not needed. This is in reference to the number 1 found after the CD144 format
4-3
-------
keyword with the SURFACE DATA keyword. The next message, 101, indicates that stage 1
processing is being performed. Message 159 indicates the ASOS commission date of the
station. The first occurrence of message 140 indicates that SURFACE extraction has begun with
the processing start date and time. Messages 146 through 156 indicate the number of
observations that are extracted, retained or valid, duplicate observations, overwritten
observations, and calms. The second 140 message indicates the date and time that SURFACE
extraction ended. The remaining messages are quality assurance messages and give the date and
times, in Local Standard Time, of the observations thai were llauucd as calm. Note that there
are twenty Q43 messages, corresponding to the number of obser\ alions flagged as calm with the
156 message.
Figure 4-4 through Figure 4-6 show 1 lie contents of the report file.
EX01_S1_SURFACE_REPORT.TXT. Figure 4-4 shows the file summary of slage 1. Shown
are the AERMET version number, start processing lime, and the name of the AERMET control
file. Following is the input summary of stage (stage I) and the filenames of input and output
files for each path. If a path is not being processed. AI-RMET will denote by listing the path
along with "NO PROCESSING RI-QITESTI-1) "" I or paths being processed, the file status
along with the filename is listed I'or optional operations, such as debugging, if the DEBUG
option is not chosen. AI-RMI-T will list "NO I'll.IT for the filename. Station information (site
identifier. coordinates time adjustment. ele\ation) for upper air, surface, site-specific, or
prognostic is also summarized along with the requested dates for the station.
I'iuure 4-5 shows the ().\ summary of the surface extraction. Since no specific variables
were requested lor auditing \ ia the AUDIT keyword, only temperature, wind direction, and
wind speed were audited by default. The report file shows the audited variables with their
missing value indicators and lower and upper bounds. Note that the missing value indicators are
not subject to the conversion factor for the surface variables while the bounds have the
conversion factor applied (See Table B-l in Appendix B). Next, follows the number of
observations read in for each variable, the number of missing observations, number of
observations that exceed the lower and upper bounds, and percent of observations that were
4-4
-------
accepted. In this example, no data was missing so all data was accepted. The final summary list
the following:
the number of calm wind observations
number of observations with zero wind direction and non-zero wind speed
number of observations with non-zero wind direction and zero wind speed,
number of observations where the temperature u as less than the dewpoint
number of observations with precipitation but 110 weather code and,
number of observations with a weather code hul 110 precipitation
Figure 4-6 shows the message summary portion of the report file. The message file
summarizes the number of each type of message error, warning, information, and quality
assurance message. If the number of messages for a specific message type is greater than zero,
then AERMET also issues the number of each message code associated with the message type.
For the example, there are no error messages and there was one warning message, W01. There
were nine information messages distributed among |n|. 14'). T4(\ 147,150,153,156, and 159.
There was one OA message. 043 After the message summary, AERMET notifies the user that
AERMET completed successfully, along with the end date and time of AERMET processing.
finally, figure 4-7 shows the formal of the EXTRACT file, SURFACEEXTRACT.
The QAOl T file has a similar formal The header information gives the AERMET version,
location information (station identifier, coordinates, time conversion and elevation). Next,
follows the file type (EXTRACT or QAOUT), processing dates and the header for the data
column. If audited \ ariahles used different defaults for missing or bound values, those would be
indicated as well in the header Following the data header, are the actual data and is formatted
as described in
4-5
-------
Table C-l of Appendix C. For variable names see Table B-l in Appendix B.
4-6
-------
SURFACE
W01
SURF PATH
TOO MANY
FIELDS 4
FOR DATA KEYWORD; BLOCKING FACTOR AND/OR TYPE NOT NEEDED
101
READINP
PROCESSING STAGE 1
SURFACE
159
SF TEST
STATION
14735
AS OS
COMMISSION DATE: 19950801
SURFACE
140
SF PROC
SURFACE EXTRACTION BEGIN: 20211108 11:31:06
SURFACE
146
SF PROC
NUMBER OF EXTRACTED
SURFACE OBSERVATIONS: 240
SURFACE
147
SF PROC
NUMBER OF RETAINED OBSERVATION :
SURFACE
150
SF PROC
NUMER OF
DUPLICATE OBSERVATIONS NOT USED: 0
SURFACE
153
SF PROC
NUMBER OF OVERWRITTEN OBSERVATIONS: 0
SURFACE
156
SF PROC
NUMBER OF OBSERVATIONS FLAGGED AS CALM 2 0
SURFACE
140
SF PROC
SURFACE EXTRACTION END: 2 02 .: : ¦
SURFACE
Q43
SF AUDIT
19880302
HR
02
CALM
WIND
SURFACE
Q43
SF AUDIT
19880302
HR
03
CALM
WIND
SURFACE
Q43
SF AUDIT
19880302
HR
04
CALM
WIND
SURFACE
Q43
SF AUDIT
19880302
HR
05
CALM
WIND
SURFACE
Q43
SF AUDIT
19880302
HR
06
CALM
WIND
SURFACE
Q43
SF AUDIT
19880302
HR
07
CALM
WIND
SURFACE
Q43
SF AUDIT
19880303
HR
19
WIND
SURFACE
Q43
SF AUDIT
19880303
HR
21
r^
WIND
SURFACE
Q43
SF AUDIT
19880305
HR
24
CALM
WIND
SURFACE
Q43
SF AUDIT
19880306
HR
01
CALM
WIND
SURFACE
Q43
SF AUDIT
19880306
HR
02
CALM
WIND
SURFACE
Q43
SF AUDIT
19880306
HR
03
CALM
WIND
SURFACE
Q43
SF AUDIT
19880306
HR
04
CALM
WIND
SURFACE
Q43
SF AUDIT
19880306
HR
05
LM
WIND
SURFACE
Q43
SF AUDIT
19880306
HR
0 6
CALM
WINI
SURFACE
Q43
SF AUDIT
19880306
HR
07
CALM
WINI
SURFACE
Q43
SF AUDIT
1988"
HR
21
CALM
WINI
SURFACE
Q43
SF AUI
19880308
HR
22
CALM
WIND
SURFACE
Q43
SF AUDIT
19880308
SURFACE
Q43
SF AUDIT
19880309
Figure 4-3. Contents of the SURI-ACK extrsu'lion messsige file.
4-7
-------
AERMET VERSION 21DRF
START PROCESSING DATE/TIME: NOVEMBER 08, 2021 11:31:02 AM
RUNSTREAM CONTROL FILE: EX01 SURFACE.INP
**************************** INPUT SUMMARY ****************************
AERMET SETUP SUCCESSFUL
PROCESSING STAGES 1
1. JOB FILE NAMES
MESSAGES OPEN EX01 SI SURFACE MES .
REPORT OPEN EX01 SI SURFACE REI
DEBUG NO FILE
2. UPPERAIR DATA
NO PROCESSING REQUESTED
3. SURFACE DAm""
PROCESSING DA" :
] TIME ADu uo i'MENT
ELEVATION
L0C"m"": . . 0
83 .80
DAI :
EXI :
QAC :
4 . ONS
NO PROCESS
5. PROG DATA
NO PROCESSING REQUESTED
6. METPREP DATA
NO PROCESSING REQUESTED
Figure 4-4. Input summary contents of the SURFACE extraction report file.
4-8
-------
SURFACE DATA
VARIABLE MISSING VALUE LOWER
BOUND
UPPER BOUND
TMPD 999.00 <= -30
.00
>= 40.00
WDIR 999.00 < 0.00
> 360.00
WSPD 999.00 < 0.00
> 50.00
VARIABLE # #
LOWER
UPPER
Q.
O
OBS MISSING
BOUND
BOUND
ACCEPTED
TMPD 240 0
0
0
100.00
WDIR 240 0
0
0
100.00
WSPD 240 0
0
0
100.00
WIND, TEMPERATURE, AND PRECIPITATION CHECKS
NUMBER OF HOURS:
20 CALM WINDS (WDIR = 0, WSP:
= 0)
0 WDIR = 0, WSPD > 0
0 WDIR > 0, WSPD = 0
0 TEMPERATURE < DEWPOINT
0 PRECIP WITHOUT WEATHER COD
0 WEATHER CODE WITF
Figure 4-5. QA summary contents of the SI UI- AC'K extraction report file.
4-9
-------
MESSAGE SUMMARY 'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k'k
ERROR MESSAGES 0 MESSAGES
WARNING MESSAGES 1 MESSAGES
W01: 1
INFORMATION MESSAGES 9 MESSAGES
101: 1
140: 2
146: 1
147: 1
150: 1
153: 1
156: 1
159: 1
QA MESSAGES 2 0 MESSAGES
Q43: 20
AERMET FINISHED SUCCESSFULLY
END PROCESSING DATE/TIME: NOVEMBER 08, 2021 11:31:06 AM
Figure 4-6. Message summary contents of the SURFACE extraction report file.
4-10
-------
AERMET 21DRF
LOCATION 14735 42.750N 73.800W 0 83.800
FILE TYPE: EXTRACT
DATES 1988 03 01 1988 03 10
DATE
HR
ASOS
PRCP
SLVP
PRES
TSKC
PWTH
ASKY
TMPD
DPTP
RHUM
WDIR
WSPD
19880301
01
N
-9. 00
99999.0
1003.0
404.0
0.0
99. 0
-2.8
999. 0
999.0
270. 0
3.1
19880301
02
N
-9. 00
99999.0
1003.0
101. 0
0.0
99. 0
-2.8
999. 0
999.0
280.0
4.1
19880301
03
N
-9. 00
99999.0
1003.0
101. 0
99. 0
-3.9
999. 0
999.0
280.0
4.1
19880301
04
N
-9. 00
99999.0
1003.0
101. 0
99. 0
-5.0
999. 0
999.0
290. 0
5.1
19880301
05
N
-9. 00
99999.0
1003.0
0.0
99. 0
. 6
999. 0
999.0
290. 0
5.7
19880301
06
N
-9. 00
99999.0
1004.1
0.0
99. 0
-5 . 6
999. 0
999.0
290. 0
2 . 6
19880301
07
N
-9. 00
99999.0
1004.1
0.0
99. 0
-6.1
999. 0
999.0
290. 0
5.1
19880301
08
N
-9. 00
99999.0
1005.1
606. 0
99. 0
-5 . 6
999. 0
999.0
310. 0
4.1
19880301
09
N
-9. 00
99999.0
1005.1
707. 0
99. 0
999. 0
999.0
270. 0
7.2
19880301
10
N
-9. 00
99999.0
1005.1
606. 0
99. 0
999. 0
999.0
300. 0
8.2
19880301
11
N
-9. 00
99999.0
1005.1
202.0
99. 0
-4.4
999. 0
999.0
300. 0
7.7
19880301
12
N
-9. 00
99999.0
1004.1
0.0
99. 0
-4.4
999. 0
999.0
270. 0
8.8
19880301
13
N
-9. 00
99999.0
1003.0
0 . 0
99. 0
-3.9
999. 0
999.0
270. 0
9.3
19880301
14
N
-9. 00
99999.0
1002.0
0 . 0
-3.9
999. 0
999.0
310. 0
7.2
19880301
15
N
-9. 00
99999.0
1002.0
0.0
-4.4
999. 0
999.0
260. 0
9.3
19880301
16
N
-9. 00
99999.0
1001.0
-4.4
999. 0
999.0
270. 0
7.2
Figure 4-7. Format of the SURFACE EXTRACT :iml QAOl I liles.
4-11
-------
4.1.2 Upper air data
The next example is for the upper air data for Albany, NY for the same ten-day period as
the surface data example. Figure 4-8 shows the stage 1 control file, EX01 UPPER. INP. The
raw upper air data are in 6201 format and extracted and QA data will be written to
UPPER_EXTRACT.TXT andUPPER_QAOUT.TXT respectively. Note that temperature,
wind speed, and lapse rate are requested for QA.
JOB
REPORT
MESSAGES
EX01 SI UPPER REPORT.TXT
EX01 SI UPPER MESSAGE.TXT
UPPERAIR
DATA
EXTRACT
QAOUT
14735-88.UA 6201FB 1
UPPER EXTRACT.TXT
UPPER QAOUT.TXT
XDATES
1988/3/1 TO 1988/_
LOCATION
AUDIT
14735 73.SOW 42.75N 5 83.8
UA
** 725180 14735 ALBANY COUNTY AP
US US NY KALB
+42750 -073800 +00838
Figure 4-8. Control file (o extract and QA NWS upper air data.
To execute AI-RMI-T slime I lor this example, the user would type the following at the
command prompt.
aermel e\e l-.\<)| I PPERTM'
assuming the control file unci ALRMET executable are in the same folder. Processing
information will be written to the screen. If the user wishes to have that information written to a
text file, the user would type the following at the command prompt:
aermet.exe EX01 SURF ACE . INP > example_upper.txt
4-12
-------
The contents of example_upper.txt are shown in Figure 4-9 and show the AERMET
processing. The first line gives the start date and time of the AERMET processing. The next
ten lines notify the user of the extraction dates followed by ten lines denoting each day's data
are being QA'd. The final messages are that AERMET completed successfully followed by the
AERMET processing end date and time.
START
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
PROCESSING DATE/TIME:
Extracting upper
Extracting upper
Extracting upper
Extracting upper
Extracting upper
Extracting upper
Extracting upper
Extracting upper
Extracting upper
Extracting upper
QA'ing upper air
QA'ing upper air
QA'ing upper air
QA'ing upper air
QA'ing upper air
QA'ing upper air
QA'incr upper air
QA'ing upper air
QA'ing upper air
QA'ing UDDer air
NOVEMBER 08, ",,r:?8:39 PM
air data for month/day/year 03/01/1988
air data for month/day/year 03/02/1988
air data for month/day/year 03/03/1988
air data for month/dav/vear 03/04/1988
air data for month/day/year 03/05/1988
air data for month/day/year 03/06/1988
air data for month/day/year 03/07/1988
air data for month/day/year 03/08/1988
air data for month/day/year 03/09/1988
air data for month/day/year 03/10/1988
data for month/day/year 03/01/1988 LST
data for month/day/year 03/02/1988 LST
data for month/day/year 03/03/1988 LST
data for month/day/year 03/04/1988 LST
data for month/day/year 03/05/1988 LST
aata ror month/day/year 03/06/1988 LST
data for month/day/year 03/07/1988 LST
data for month/day/year 03/08/1988 LST
data for month/day/year 03/09/1988 LST
data for month/day/year 03/10/1988 LST
LST
LST
LST
LST
LST
LST
LST
LST
LST
LST
AERMET FINISHED SUCCESSFULLY
END PROCESSING DATE/TIME: NOVEMBER 08, 2021 15:28:39 PM
Figure 4-9. Processing steps for NWS upper air data extraction.
Figure 4-10 shows ilie processing messages contained
EX01_S1_UPPER_MESSAGE.TXT. As with the surface example, messages that start with
'W' are warning messages, T are informational messages, 'E' are error messages and 'Q' are
quality assurance messages. The very first message is a warning message indicating that too
many fields were found with the DATA keyword and that the blocking factor or type was not
needed. This is in reference to the number 1 found after the 6201 format keyword with the
UPPERAIR DATA keyword. The second W01 message indicates elevation is not needed for
4-13
-------
upper air data. The third message, 101 indicates that stage 1 processing is being performed. The
first occurrence of message 120 indicates that UPPERAIR extraction has begun with the
processing state date and time. Messages 122 through 126 indicate the number of extracted
soundings, number of unique valid soundings, number of duplicate soundings, and number of
skipped soundings. The second 120 message indicates the date and time that the UPPERAIR
extraction ended. The remaining messages are related to QA. Message Q28 alerts the user that
the sounding for March 1, 1988 hour 19 has a sounding lop of 0 m and is less than 5 km. The
Q23 messages indicate missing data for a particular level, and Q24 and Q25 refer to violations
of the lower and upper bounds, respectively.
Figure 4-11 through Figure 4-15 show the conlenl of the E.\<)| I PPF. R_REPORT.TXT.
Figure 4-11 shows the file summary of stage I The first lines list the AI-RMF.T version
number, start processing time, and the name of the AI-RMI-T control file. Following is the
input summary of stage (stage 1) and the filenames of input and output files for each path. If a
path is not being processed, AERMI-T will denote In listing the path along with "NO
PROCESSINGREQIT.STF.D For paths heing processed, the lile status along with the
filename is listed. For optional operations, such as debugging, if the DEBUG option is not
chosen, AERMET will list "NO FII.F" for the filename Station information (site identifier,
coordinates time adjustment. ele\ation) lor upper air. surface, site-specific, or prognostic is also
summarized along with the requested dates for the station.
I'igure 4-12 through I'igure 4-14 show the QA summary of the upper air extraction.
Figure 4-12 shows the missing \ nine indicators and bounds for the audited variables
(temperature, wind speed, and lapse rate). Note that the missing value indicators are not subject
to the conversion factor lor the surface variables while the bounds have the conversion factor
applied (See Table B-2 in Appendix B). Next in Figure 4-13, follows the number of
observations read in for each variable, the number of missing observations, number of
observations that exceed the lower and upper bounds, and percent of observations that were
accepted by level. The individual sounding levels are grouped into layers. For temperature and
wind speed, 100%o of the data was accepted but lapse rate acceptance was less than 100% for
some layers. Finally, in Figure 4-14 are summaries of the following:
4-14
-------
the number of calm wind observations
number of observations with non-zero wind direction and zero wind speed,
number of observations where the temperature was less than the dewpoint and,
number of soundings that do not extend to 5,000 m
Figure 4-15 shows the message summary portion of the report file. The message file
summarizes the number of each type of message: error, warning, information, and quality
assurance message. If the number of messages for a specific message type is greater than zero,
then AERMET also issues the number of each message code associated with the message type.
For the example, there are no error messages and there were two warning messages, W01.
There were eight information messages distrilulled among 101,120, 122. 123. T24,125, and 126.
There were nine QA messages distributed among Q23 through Q28. After the message
summary, AERMET notifies the user that AERMET completed successfully, along with the end
date and time of AERMET processi ng.
Finally, figure 4-l(-> shows the formal of the l-XTR.\('T file.
UPPERAIREXTRACT TXT The header information if much like the EXTRACT file for
SURFACE data and gi\es the AliRMIT \ ersion. location information (station identifier,
coordinates, time coin ersion and ele\ation) \e\t. follows the file type (EXTRACT or
QAOl T). processi ng dates and the header for the data columns. If audited variables used
different delimits for missing or hound \ allies, those would be indicated as well in the header.
Following the data header, are the actual data and is formatted as described in Table C-2 of
Appendix C Tor \ ariaMe names see Table B-2 in Appendix B. The QAOUT file, shown in
Figure 4-17, has a similar formal with the exception that it also lists the values for the audited
variable, UALR (lapse rale) I or both SURFACE and UPPERAIR EXTRACT and QAOUT
files, the EXTRACT files contain variables needed by METPREP. The QAOUT files contain
those same variables plus any additional audited variables, such as UALR, that are not needed
by METPREP.
4-15
-------
101
120
122
123
124
125
126
120
Q2 8
Q23
Q23
Q23
Q2 4
Q25
Q25
Q2 4
4-1
UPPER PATH TOO MANY FIELDS
4 FOR DATA KEYWORD;
NG FACTOR AND/OR TYPE NOT NEEDED
GETLOC STATION ELEVATION NOT NEEDED
READINP PROCESSING STAGE 1
UP_PROC UPPER AIR EXTRACTION BEGIN
READ_6201 END OF DATA WINDOW ENCOUNTE
UP_PROC NUMBER OF EXTRACTED SOUNDIK :
UP_PROC NUMBER OF UNIQUE VALID SOUNDINGS:
UP_PROC NUMBER OF DUPLICATE SOUNDIN':
UP_PROC NUMBER OF SKIPPED SOUNDINGS:
UP PROC UPPER AIR EXTRACTION END 20ziiiub
:o
±o : 28:39
UP
AUDIT
19880301
HR
19
TOP OF SOUNDING
" <
5000 M
UP
AUDIT
19880302
HR
07
UAWS
MISSING
FOR
LEVEL
8
up"
AUDIT
19880302
HR
07
UAWS
MISSING
FOR
LEVEL
)
UP
AUDIT
19880302
HR
07
UAWS
MISSING
LEVEL
i
up"
AUDIT
19880304
HR
19
UALR
. i
LEVEL
8
UP
AUDIT
19880306
HR
07
UALR
T"""L
2
up"
AUDIT
19880306
HR
07
UALR
.
L
3
UP
AUDIT
19880309
HR
19
U
.
L
2
UP AUDIT
3.0 LEVEL
Contents of the I PPKUAIU exlrsiclion message file.
4-16
-------
AERMET VERSION 21DRF
START PROCESSING DATE/TIME: NOVEMBER 08, 2021 15:28:39 PM
RUNSTREAM CONTROL FILE: EX01_UPPER.INP
INPUT SUMMARY ****************************
AERMET_SETUP SUCCESSFUL
PROCESSING STAGES 1
1. JOB FILE NAMES
MESSAGES OPEN EX01_S1_UPPER_MESSAGE.TXT
REPORT OPEN EX01_S1_UPPER_REPORT.TXT
DEBUG NO FILE
2. UPPERAIR DATA
PROCESSING DATES: 03/01/1988 - 03/10/1988
SITE ID LATITUDE
00014735
LOCATION:
DATA FILE:
EXTRACT FILE:
QAOUT FILE:
OPEN
OPEN
OPEN
14735-
UPPER
upper" QAO
UPPER AIR DATA AB'
UPPER AIR AUT(
.CTEI
: OI _
LOK
ADJUSTMENT
5
3.
NO
4 . ONS
NO PROCESS
5. PROG DATA
NO PROCESSING REQUESTED
6. METPREP DATA
NO PROCESSING REQUESTED
Figure 4-11. Input summary contents of the UPPERAIR extraction report file.
4-17
-------
**************************
** QA SUMMARY
****************************
UPPERAIR DATA
VARIABLE MISSING VALUE
LOWER BOUND
UPPER BOUND
UATT -9990.00
<= -35.00
>= 35.00
UAWS 9990.00
<0.00
> 50.00
UALR -9999.00
<= -2.00
o
o
LO
II
A
Figure 4-12. Initial QA summary contents of 1 lie I PPKUAIR extraction report file.
4-18
-------
LEVEL
VARIABLE
#
#
LOWER
UPPER
%
OBS
MISSING
BOUND
BOUND
ACCEPTED
SURFACE
UATT
20
0
0
0
100.00
UAWS
20
0
0
0
1 . 00
0
500 M
UATT
65
0
0
0
. )0
UAWS
65
0
0
. )0
UALR
65
0
1
. 18
500
- 1000 M
UATT
46
0
0
UAWS
46
3
0
UALR
46
0
0
1000
- 1500 M
UATT
43
0
0
100 .
UAWS
43
0
0
0
100.00
UALR
43
0
1
97 . 67
1500
- 2000 M
UATT
49
0
-
o
o
UAWS
49
0
o
o
UALR
49
0
. 96
2000
- 2500 M
UATT
50
0
UAWS
50
0
UALR
2500
- 3000 M
UATT
UAWS
UALR
3000
- 3500 M
UATT
100.00
100.00
100.00
3500
- 4000 M
100.00
100.00
--
0
100.00
> 4000 M
UATT
76
0
100.00
UAWS
6
0
100.00
UALR
0
0
100.00
Figure 4-13. QA summary con louts of the I I'PERAIR extraction report file.
4-19
-------
NON-QA SUMMARY CHECKS
CALM WIND CONDITIONS (WS=0, WD=0): 0
ZERO WIND SPEED; NON-ZERO WIND DIRECTION: 0
DEW POINT GREATER THAN DRY BULB TEMPERATURE:
0
NUMBER OF SOUNDINGS THAT DO NOT EXTEND TO 5000 M:
1
Figure 4-14. Final QA summay contents of the UPPERAIR extraction report file.
MESSAGE SUMMARY
ERROR MESSAGES 0 MESSAGES
WARNING MESSAGES 2 MESSAGES
W01: 2
INFORMATION MESSAGES 8 M!
101: 1
120: 2
122: 1
123: 1
124: 1
125: 1
126: 1
QA MESSAGES 9 MESSi
Q23 :
Q24 :
Q25 :
Q28 :
AERMET FINISHED SUCCESSFULLY
END PROCESSING DATE/TIME: NOVEMBER 08, 2021 15:28:39 PM
Figure 4-15. Message summary contents of the UPPERAIR extraction report file.
4-20
-------
AERMET 21DRF
LOCATION 00014735 42.750N 73.800W 5 83.800
FILE TYPE: EXTRACT
DATES 1988 03 01 1988 03 10
DATE
SND
HR
LEV
UAPR
UAHT
UATT
19880301
1
07
1
1011.3
0.0
-5.9
19880301
1
07
2
1008 . 0
26.0
-6.0
19880301
1
07
3
1000. 0
88 . 0
-6.1
19880301
1
07
4
950. 0
487 . 0
-9.0
19880301
1
07
5
930. 0
652 . 0
-10.3
19880301
1
07
6
913. 0
794 . 0
-9.7
19880301
1
07
7
900. 0
905. 0
-10. 1
19880301
1
07
8
884 . 0
1043. 0
-10. 6
19880301
1
07
9
870. 0
1166.0
-10. 9
19880301
1
07
10
850. 0
1345. 0
19880301
1
07
11
821. 0
1611. 0
19880301
1
07
12
804 . 0
1770. 0
19880301
1
07
13
800. 0
1808 . 0
19880301
1
07
14
785. 0
1951. 0
19880301
1
07
15
750. C
2294 . 0
J. 1 .
19880301
1
07
16
74,- . r
2354 . 0
-18 . 0
19880301
1
07
17
70i .
2806.0
-22 . 1
19880301
1
07
18
65 0. ^
3347 . 0
-25.5
19880301
1
07
19
636.
3505. 0
-26.6
19880301
1
07
20
626. 0
3619. 0
-26.9
19880301
1
07
21
617 . 0
3724 . 0
-26.5
19880301
1
07
22
ouO. 0
3926.0
-26.2
19880301
1
07
23
594 . 0
3999. 0
-26.0
19880301
1
07
24
55 .
-28 . 9
19880301
1
07
500. 0
'3 9
251
0
21.0
¦ . '
249
0
22 . 0
1
(
\
237
0
24 . 0
1
CO
CO
232
0
29.0
4-21
-------
AERMET 21DRF
LOCATION 00014735 42.750N 73.800W 5 83.800
FILE TYPE: QAOUT
DATES 1988 03 01 1988 03 10
DATE
SND
HR
LEV
UAPR
UAHT
UATT
19880301
1
07
1
1011
3
0
0
-5.9
19880301
1
07
2
1008
0
26
0
-6.0
19880301
1
07
3
1000
0
88
0
-6.1
19880301
1
07
4
950
0
487
0
19880301
1
07
5
930
0
652
0
19880301
1
07
6
913
0
794
0
19880301
1
07
7
900
0
905
0
19880301
1
07
8
884
0
1043
0
19880301
1
07
9
87
19880301
1
07
10
85
-11.5
19880301
1
07
11
82
-12 . 9
19880301
1
07
12
804
-1 " . 2
19880301
1
07
13
80
-14 . 4
19880301
1
07
7 ° 5
19880301
1
07
19880301
1
07
lb
744
19880301
1
0'
70
19880301
1
0'
650
334 7
-9 ^ . 5
19880301
1
0'.
±y
63 6
0
3505
-ZD. 6
19880301
1
07
20
62 6
0
3619
-26.9
19880301
1
07
617
0
3724
-26.5
19880301
1
07
22
600
0
3926
-26.2
19880301
1
07
23
594
0
3999
-26.0
19880301
1
07
24
550
0
-28 . 9
19880301
1
07
25
500
0
u
-32 . 6
Figure 4-17. Format of the UPPERA1R QAOUT file.
:d
UAW
UAWS
UALR
-10.5
280. .
-9999.0
.:: :5 . 0
-0.4
>0. 0
-0.2
14.0
. .
-0.7
14 . 0
12 . 0
-0.8
-25.5
oqo ri
12 . 0
0.4
12 . 0
-0.4
-24 . 4
12 . 0
-0.4
¦|/1 o
13. 0
-0.2
13. 0
-0.3
- . _
282. 0
13. 0
-0.5
1.0
280.0
13. 0
-0.8
-20.2
279. 0
13. 0
-0.5
279. 0
14 . 0
-0.8
279. 0
15. 0
-0.6
. i
279. 0
16.0
-0.7
. i
275. 0
19. 0
-0.9
-28.2
268 . 0
23. 0
-0.6
-29.3
265. 0
22 . 0
-0.7
-35.2
262 . 0
21.0
-0.3
1
M
CO
258 . 0
21.0
0.4
-41.9
251. 0
21.0
0.1
-42 . 7
249. 0
22 . 0
0.3
-45. 1
237 . 0
24 . 0
-0.5
1
CO
CO
232 . 0
29.0
-0.5
4-22
-------
4.1.3 Data merger and boundary layer calculations
After extracting the surface and upper air data, the next step is to merge the two datasets
and calculate boundary layer parameters in stage 2. The AERMET stage 2 control file,
EX01NWS S2.INP is shown in Figure 4-18. The QAOUT files from the upper air extraction
and surface extraction are shown in the UPPERAIR and SURFACE pathways. The METPREP
pathway lists the two output files, EX01NWS.SFC and EX<~>1 WVS.PFL, Options include
NWS substitution and randomization of the wind directions. The NWS anemometer height is
listed as 6.1 m. Surface characteristics are annual for one 3M) sector. The location coordinates
are those of the source, not the meteorological station as described in Section 0.
JOB
REPORT
EX01 NWS S2 REPORT.TXT
MESSAGES
EX01 NWS S2 MESSAGE.TXT
UPPERAIR
QAOUT
UPPER QAOUT.TXT
SURFACE
QAOUT
SURFACE QAOUT.TXT
METPREP
OUTPUT
EX01 NWS.S FC
PROFILE
EX01 NWS.P FL
LOCATION
MYSITE 74.00W 41.3N 5
METHOD
REFLEVEL SUBNWS
METHOD
WIND DIR. RANDOM
NWS_HGT
WIND 6.1
FREQ_SECT
ANNUAL 1
SECTOF
SITE CIIAI'
** 725180 14
735 ALBANY COUNTY AP
US US NY KALB +42750 -073800 +00838
Figure 4-IS. Control file lor boundary layer calculations in METPREP.
To execute AERMI -T stage 2 for this example, the user would type the following at the
command prompt:
aermet.exe EX01 NWS S2.INP
4-23
-------
assuming the control file and AERMET executable are in the same folder. Processing
information will be written to the screen. If the user wishes to have that information written to a
text file, the user would type the following at the command prompt:
aermet.exe EX01 SURF ACE . INP > example_stage2.txt
The contents of example_stage2.txt are shown in Figure 4-19 and show the AERMET
processing. The first line lists the start date and time of I lie AI-RMET processing. The next ten
lines notify the user of the upper air extraction dates followed In leu lines denoting surface
extraction dates. The next ten lines denote that initial data assignments for variables such as
wind and temperature and the next ten lines denote I'liL calculations are heing done. The final
messages are that AERMET completed successfully followed by the AI-RMI-T processing end
date and time.
The contents of the message file. I- \<> I MVS S2_\II-SSAGE.TXT are shown in Figure
4-20 and Figure 4-21 Figure 4-20 shows the initial message that stage 2 is being processed
along with warning messages that the upper air ele\ ation is not needed, and that the
LOCATION keyword is not needed forMI-TPR!-!' Next, follow messages regarding upper air
and surface data extraction, including that the NW S station is an ASOS station but the extracted
data are before the commission date The I'lil. calculations begin with message 170 and the date
and ti me of the start of proccssi nu Next, follows the message that the solar angle approach will
be used to determine stability Remaining messages in Figure 4-20 and messages in Figure 4-21
refer to PBL calculations such as what sounding is used for each day (177), whether the
sounding is extended or not (\Y7(->), and messages about skipping calculations due to missing
data (172).
4-24
-------
START
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
PROCESSING DATE/TIME: NOVEMBER 09, 2021 15:36:59 PM
Extracting upper air data for month/day/year 03/01/1988 LST
Extracting upper air data for month/day/year 03/02/1988 LST
Extracting upper air data for month/day/year 03/03/1988 LST
Extracting upper air data for month/day/year 03/04/1988 LST
Extracting upper air data for month/day/year 03/05/1988 LST
Extracting upper air data for month/day/year 03/06/1988 LST
Extracting upper air data for month/day/year 03/07/1988 LST
Extracting upper air data for month/day/year 03/08/1988 LST
Extracting upper air data for month/day/year 03/09/1988 LST
Extracting upper air data for month/day/year 03/10/1988 LST
Extracting surface data for month/day/year 03/01/1988 LST
Extracting surface data for month/day/year 03/02/1988 LST
Extracting surface data for month/day/year 03/03/1988 LST
Extracting surface data for month/day/year 03/04/1988 LST
Extracting surface data for month/day/year 03/05/1988 LST
Extracting surface data for month/day/year 03/06/1988 LST
Extracting surface data for month/day/year 03/07/1988 LST
Extracting surface data for month/day/year 03/08/1988 LST
Extracting surface data for month/day/year 03/09/1988 LST
Extracting surface data for month/day/year 03/10/1988 LST
Initial data assignments for month/day/year 03/01/1988 LST
Initial data assignments for month/day/year 03/02/1988 LST
Initial data assignments for month/day/year 03/03/1988 LST
Initial data assignments for month/day/year 03/04/1988 LST
Initial data assignments for month/day/year 03/05/1988 LST
Initial data assignments for month/day/year 03/06/1988 LST
Initial data assignments for month/day/year 03/07/1988 LST
Initial data assignments for month/day/year 03/08/1988 LST
Initial data assignments for month/day/year 03/09/1988 LST
Initial data assignments for month/day/year 03/10/1988 LST
PBL calculations for month/day/year 03/01/1988 LST
PBL calculations for month/day/year
PBL calculations for month/day/year
m ' ¦¦ i i ' :ulations for month/day/year
PBL calculations for month/day/year 03/05/1988 LST
PBL calculations for month/day/year 03/06/1988 LST
PBL calculations for month/day/year 03/07/1988 LST
PBL calculations for month/day/year 03/08/1988 LST
PBL calculations for month/day/year 03/09/1988 LST
PBL calculations for month/day/year 03/10/1988 LST
03/02/1988 LST
03/03/1988 LST
03/04/1988 LST
AERMET FINISHED SUCCESSFULLY
END PROCESSING DATE/TIME: NOVEMBER 09, 2021 15:36:59 PM
Figure 4-19. Processing steps for boundary layer calculations
4-25
-------
101
W01
W70
120
123
124
125
126
120
140
W45
W45
W45
W45
W45
W45
W45
W45
W45
W45
146
147
140
170
183
111
W7 6
111
W7 6
172
172
172
172
172
172
s 4-2
READINP PROCESSING STAGE 2
GETLOC STATION ELEVATION NOT NEEDED
PBL_TEST LOCATION KEYWORD NOT NEEDED
UP_PROC UPPER AIR EXTRACTION BEGIN 202 " : :
UP_PROC NUMBER OF EXTRACTED SOUNDINGS:
UP_PROC NUMBER OF UNIQUE VALID SOUNDIN :
UP_PROC NUMBER OF DUPLICATE SOUNDINGS:
UP_PROC NUMBER OF SKIPPED SOUNDINGS:
UP_PROC UPPER AIR EXTRACTION END 20211 i ¦ : ¦ : ¦
SF PROC SURFACE EXTRACTION BEGIN: 20211109 15:36:59
CHECK
AS OS
STATION
IS
AS OS,
BUT
BEFO
COMMISSION
19950801
FOR
DATE
19880301
CHECK
AS OS
STATION
IS
AS OS,
BUT
BEFO
COMMISSION
DATE
19950801
FOR
DATE
19880302
CHECK
AS OS
STATION
IS
AS OS,
BUT
BEFO
COMMISSION
DATE
19950801
FOR
DATE
19880303
CHECK
AS OS
STATION
IS
AS OS,
BUT
BEFO
COMMISSION
DATE
19950801
FOR
DATE
19880304
CHECK
AS OS
STATION
IS
AS OS,
BUT
BEFO
COMMISSION
DATE
19950801
DATE
19880305
CHECK
AS OS
STATION
IS
AS OS,
BUT
BEFORE
COMMISSION
.TE
19950801
DATE
19880306
CHECK
AS OS
STATION
IS
AS OS,
BUT
f.EF'"'RE
COMMISSION
L* JE
19950801
V UU
DATE
19880307
CHECK
AS OS
STATION
IS
AS OS,
'¦ 11 'i I1'1 'RE
COMMISSION
DATE
19950801
FOR
DATE
19880308
CHECK
AS OS
STATION
IS
AS OS,
'¦ 11 'i I1'1 'RE
COMMISSION
DATE
19950801
FOR
DATE
19880309
CHECK
AS OS
STATION
IS
AS OS,
N'1,!'1' 'RE
COMMISSION
DATE
19950801
FOR
DATE
19880310
SF PROC
NUMBER OF EXTRACTED
SURFACE
OBSERVATIONS:
240
NUMBER OF RETAINED OBSERVATION
SURFACE EXTRACTION END: 202111
PBL CALCULATIONS BEGIN: 20211
SOLAR. ANGLE API
SF_PROC
SF_PROC
PBL_PROC
PBL_PROC
READ_SOUND SOUNDING FOR D
READ_SOUND DATE 19880301
READ SOUND SOUNDING FOR D
READ SOUND DATE
P
P
P
PBL_PROC
PBL_l'k^C
PBL PF "
Date
:e
:e
DATE
DATE
DATE
15:36:59
15:36:59
ROACH WILL BE USED FOR STABILITY DETERMINATION
.TE: 19880301 IS 19880301 HR 07 SOUNDING # 1
OP OF SOUNDING 5.2 KM EXTENDS BEYOND 5.0 KM;
.TE: 19880302 IS 19880302 HR 07 SOUNDING # 1
OP OF SOUNDING 5.4 KM EXTENDS BEYOND 5.0 KM;
HR 02 WINDS CALM OR MISSING, SKIP CALCULATIONS
HR 03 WINDS CALM OR MISSING, SKIP CALCULATIONS
19880302 HR 04 WINDS CALM OR MISSING, SKIP CALCULATIONS
19880302 HR 05 WINDS CALM OR MISSING, SKIP CALCULATIONS
19880302 HR 06 WINDS CALM OR MISSING, SKIP CALCULATIONS
19880'": HR 07 WINDS CALM OR MISSING, SKIP CALCULATIONS
19880302
lyaaujuz
19880302
SOUNDING NOT EXTENDED
SOUNDING NOT EXTENDED
Initial contents of the stage 2 message file.
4-26
-------
177
W7 6
172
172
111
W7 6
111
W7 6
172
177
W7 6
172
172
172
172
172
172
172
177
W7 6
177
W7 6
172
172
172
111
W7 6
172
177
W7 6
^4-2
READ_S OUND
READ_S OUND
PBL_PROC
PBL_PROC
READ_S OUND
READ_S OUND
READ_S OUND
READ_S OUND
PBL_PROC
READ_S OUND
READ_S OUND
PBL_PROC
PBL_PROC
PBL_PROC
PBL_PROC
PBL_PROC
PBL_PROC
PBL_PROC
READ_S OUND
READ_S OUND
READ_S OUND
READ_S OUND
PBL_PROC
PBL_PROC
PBL_PROC
READ_S OUND
READ_S OUND
PBL_PROC
READ_S OUND
READ SOUND
SOUNDING FOR DATE: 19880303 IS 1988
DATE 19880303 TOP OF SOUNDING 5.4
DATE: 19880303 HR 19 WINDS CALM OR
DATE: 19880303 HR 21 WINDS CALM OR
SOUNDING FOR DATE: 19880304 IS 1988
DATE 19880304 TOP OF SOUNDING 5.4
SOUNDING FOR DATE: 19880305 IS 1988
DATE 19880305 TOP OF SOUNDING 5.4
DATE: 19880305 HR 24 WINDS CALM OR
SOUNDING FOR DATE: 19880306 :: 1988
DATE 19880306 TOP OF SOUNDING 5.4
19880306 HR 01 WINDS CALM OR
19880306 HR 02 WINDS CALM OR
19880306 HR 03 WINDS CALM OR
19880306 HR 04 WINDS CALM OR
19880306 HR 05 WINDS CALM OR
19880306 HR 06 WINDS CALM OR
19880306 HR 07 WINDS CALM OR
SOUNDING FOR DATE: 19880307 IS 19BB
DATE 19880307 TOP OF SOUNDING 5.4
SOUNDING FOR DATE: 19880308 IS 1988
DATE 19880308 TOP OF SOUNDING 5.5
19880308 HR 21 WINDS CAIM
19880308 HR 22 WINDS CALM OR
19880308 HR 24 WINDS CALM OR
SOUNDING FOR DATE: 19880309 IS 1988
DATE 19880309 TOP OF SOUNDING 5.5
DATE: 19880309 HP 01 WINDS CALM OR
SOUNDING FOR DATE: 19880310 IS 1988
DATE 19880310 TOP OF SOUNDING 5.0
0303 HR 07 SOUNDING # 1
KM EXTENDS BEYOND 5.0 KM;
MISSING, SKIP CALCULATIONS
MISSING, SKIP CALCULATIONS
Or' ' I [R 07 SOUNDING # 1
KM EXTENDS BEYOND 5.0 KM;
0::"1' MR 07 SOUNDING # 1
KM EXTENDS BEYOND 5.0 KM;
MISSING, SKIP CALCULATIONS
0306 III' 3UNDING # 1
KM EXTENDS BEYOND 5.0 KM;
DATE
DATE
DATE
DATE
DATE
DATE
DATE
DATE
DATE
DATE
SOUNDING NOT EXTENDED
SOUNDING NOT EXTENDED
SOUNDING NOT EXTENDED
SOUNDING NOT EXTENDED
MISSING, jkiP CALCULATIONS
MISSING, SKI I ' 'ALCULATIONS
MISSING, SKIP CALCULATIONS
MISSING, SKIP CALCULATIONS
MISSING, SKIP CALCULATIONS
MISSING, SKIP CALCULATIONS
MISSING, SKIP CALCULATIONS
03 07 HR 07 SOUNDING # 1
KM EXTENDS BEYOND 5.0 KM;
0308 HR 07 SOUNDING # 1
KM EXTENDS BEYOND 5.0 KM;
MISSING, SKIP CALCULATIONS
MISSING, SKIP CALCULATIONS
MISSING, SKIP CALCULATIONS
0309 HR 07 SOUNDING # 1
KM EXTENDS BEYOND 5.0 KM;
MISSING, SKIP CALCULATIONS
0310 HR 07 SOUNDING # 1
KM EXTENDS BEYOND 5.0 KM;
SOUNDING NOT EXTENDED
SOUNDING NOT EXTENDED
SOUNDING NOT EXTENDED
SOUNDING NOT EXTENDED
Finsil contents of the slsi«o 2 incss;i«c file.
4-27
-------
Figure 4-22 through Figure 4-24 show the contents of the report file,
EX01_NWS_S2_REPORT.TXT. Figure 4-22 is like Figure 4-4and Figure 4-11 in that it shows
the summary files and locations of the upper air and surface stations. Figure 4-23 shows the
summary for the METPREP pathway, including processing dates, site location (even though not
needed), the output filenames and processing options. For this example, wind directions are
randomized, and cloud and temperature substitution are performed. Following the METPREP
summary is the surface characteristics summary where the surface characteristics for each
processed year are shown. For this example, only one year is processed and it is for one sector.
Finally, in Figure 4-24 is the message file summary, similar lo I'iunre 4-6 and Figure 4-15. For
the boundary layer calculations there were no error messages, 22 warning messages distributed
among W01, W45, W70, and W76, 43 information messages distributed among several message
types and no quality assurance messages. Finally, llie report file notifies the user AERMET
finished successfully with the date and time of program execution.
Figure 4-25 and Figure 4-26 show the contents of the two output files, EX01NWS.SFC
and EX01NWS.PFT. respecti\ ely The user is referred to TaMe C-4 and Table C-5 in
Appendix C, Section (' 2 lor the formats.
4-28
-------
AERMET VERSION 21DRF
START PROCESSING DATE/TIME: NOVEMBER 09, 2021 15:36:59 PM
RUNSTREAM CONTROL FILE: EX01 NWS S2.INP
**************************** INPUT SUMMARY ****************************
AERMET SETUP SUCCESSFUL
PROCESSING STAGES 2
1. JOB FILE NAMES
MESSAGES OPEN EX01 NWS S2 MESSAGE.TXT
REPORT OPEN EX01 NWS S2 REPORT.TXT
DEBUG NO FILE
2. UPPERAIR DATA
PROCESSING DATES: 03/01/1988 - 03/10/1988
SITE ID LATITUDE LON ADJUSTMENT
LOCATION: 00014735 . . 5
DATA FILE: NO FILENAME INPUT
EXTRACT FILE: NO FILENAME INPUT
QAOUT FILE: OPEN UPPER ¦
UPPER AIR DATA AB' CTE
UPPER AIR AUT( : OI _
3 .
PRC :
bi TIME ADJUSTMENT
ELEVATION
LOC : 14/ . -73.80 0
83 .80
ASOS COMMI : 1 'i
DATA FILE: IE I]
ASOS1MIN FILE: NO
EXTRACT FILE: NO
QAOUT FILE: O AOUT.TXT
4 . ONSITE DATA
NO PROCESSING REQUESTED
5. PROG DATA
NO PROCESSING REQUESTED
Figure 4-22. Input summary contents of the stage 2 report file.
4-29
-------
6. METPREP DATA
PROCESSING DATES: 03/01/1988 - 03/10/1988
SITE ID LATITUDE LONGITUDE
TIME ADJUSTMENT
LOCATION: -9 42.75 -73.80
5
OUTPUT FILE: OPEN EX01 NWS.SFC
PROFILE FILE: OPEN EX01 NWS.PFL
METPREP PROCESSING OPTIONS
PROCESS OPTION DESCRIPTION
WIND DIRECTION RANDOM WIND DIRECTIONS A
REFLEVEL SUBNWS NWS WINDS AND TEM
CLOUD COVER SUB CC CLOUD COVER SI
TEMPERATURE SUB TT TEMPERATURE SI
CD
) FOR MISSING ONSITE DATA
SFC chaRACTE]
PRIMARY SITE CHARACTERISTICS
YEAR: 198 8 FREQUENCY ANNUAL
NUMBER OF SECTORS: 1
YEAR BEGIN SECTOR CTOR
1988 0.
BOWEN RATIO ROUGHNESS LENGTH (M)
2.00 0.1200
Figure 4-23. METPREP sum 111:1 r\ contents of the stsige 2 report file.
4-30
-------
****** MESSAGE SUMMARY ****************************
ERROR MESSAGES
0 MESSAGES
WARNING MESSAGES
22 MESSAGES
W01
1
W4 5
10
W7 0
1
W7 6
10
INFORMATION MESSAGES
4 3 MESSAGES
101
1
120
2
123
1
124
1
125
1
126
1
140
2
146
1
147
1
170
1
172
20
177
10
183
1
QA MESSAGES
AERMET FINISHI
END
PROCESSINt
: . : :59PM
Figure 4-24. Message siiiiiinsirv contents of the stage 2 report file.
4-31
-------
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
42
750N
73
800
UA
ID:
00014735 SF
ID:
14735 OS
ID:
VERSION: 21DRF
CCVR
Sub TEMP
Sub
3
61
-30.4
0
283
-9
"ooo
-9
000 -999.
361
66.5
0.1200
2.00
1.00
3.10
275
6
1
270.3
2.0
0
-9
00
999.
1003
3
61
2
-45.5
0
392
-9
000
-9
000 -999.
588
118.1
0.1200
2.00
1.00
4 .10
279
6
1
270.3
2.0
0
-9
00
999.
1003
3
61
3
-45.7
0
392
-9
000
-9
000 -999.
588
117.5
0.1200
2.00
1.00
4 .10
279
6
1
269.2
2.0
0
-9
00
999.
1003
3
61
-58.4
0
499
-9
000
-9
000 -999.
845
190.0
0.1200
2.00
1.00
5.10
290
6
1
268.1
2.0
0
-9
00
999.
1003
3
61
5
-64 . 0
0
563
-9
000
-9
000 -999.
1012
249.2
0.1200
2.00
1.00
5.70
290
6
1
267.5
2.0
0
-9
00
999.
1003
3
61
6
-25.7
0
218
-9
000
-9
000 -999.
407
35.9
0.1200
2.00
1.00
2.60
267.5
::. i)
0
-9
00
999.
1004
3
61
7
-59.0
0
499
-9
000
-9
000 -999.
845
188.1
0.1200
2.00
1.00
5. 1 i)
267.0
::. i)
0
-9
00
999.
1004
3
61
6.3
0
420
0
241
0
009 78.
658
-1045.4
0.1200
2.00
0.38
4 1 i)
2 b7 . 5
::. i)
0
-9
00
999.
1005
3
61
66. 0
0
741
0
942
0
005 453.
1530
-551.8
0.1200
2.00
0.24
7 :: i)
268.1
::. i)
0
-9
00
999.
1005
3
61
10
132.4
0
847
1
361
0
005 683.
1863
-410.8
0.1200
2.00
0.19
8 :: i)
268.1
::. i)
0
-9
00
999.
1005
3
61
11
191.7
0
802
1
591
0
005 755.
1730
-241.2
0.1200
2.00
0.17
7.7D
268.8
::. i)
0
-9
00
999.
1005
3
61
12
211.8
0
912
1
724
0
005 867.
2082
-320.4
0.1200
2.00
0.16
8."')
268
6
1
268.8
::. i)
0
-9
00
999.
1004
3
61
13
214 . 9
0
962
1
822
0
005 1008.
2256
-370.0
0.1200
2.00
0.16
9. ,;i)
271
0
6
1
269.2
::. i)
0
-9
00
999.
1003
3
61
14
194 . 9
0
753
1
821
0
005 1108.
1631
-196.0
0.1200
2.00
0.17
')
306
6
1
269.2
::. i)
0
-9
00
999.
1002
3
61
15
152.6
0
958
1
712
0
005 1177.
2240
-514 .1
0.1200
2.00
0. l: :
9.30
256
6
1
268.8
::. i)
0
-9
00
999.
1002
3
61
16
90.0
0
743
1
454
0
005 1221.
1603
-407.7
0.1200
2.00
268
6
1
268.8
::. i)
0
-9
00
999.
1001
3
61
17
13.1
0
897
0
766
0
005 1225.
2032
-4930.7
0.1200
2.00
270
6
1
267.5
2.
0
-9
00
999.
1001
3
61
18
-64 . 0
0
889
-9
000
-9
000 -999.
2012
979.7
0.1200
2.00
266
6
1
265.9
2.
0
-9
00
999.
1001
3
61
19
-64 . 0
0
889
-9
000
-9
000 -999.
2012
979.7
0.1200
2.00
273
6
1
265.3
2.
0
-9
00
999.
1001
3
61
20
-64 . 0
0
670
-9
000
-9
000 -999.
1379
419.5
0.1200
2.00
278
6
1
264.2
')
00
999.
1002
3
61
21
-64 . 0
0
670
-9
000
-9
000 -999.
1317
419.0
0.1200
2.00
263.8
00
999.
1001
3
61
22
-53.3
0
445
-9
000
-9
000 -999.
766
147.6
0.1200
2.00
263.1
::. u
00
999.
1001
3
61
23
-33.4
0
278
-9
000
-9
000 -999.
382
57.5
0.1200
2.00
262.5
2.0
00
999.
1001
3
61
24
-26.1
0
216
-9
000
-9
000 -999.
244
34 . 6
0.120
1.00
261.4
2.0
00
999.
1001
Figure 4-25. Partial contents of the EX01_N\YS.SKC file.
4-32
-------
CO
CO
CO
1
1
6.1
1
275 . 0
3 .10
o
CO
Os]
1
99.00
o
o
CO
CO
CO
1
2
6.1
1
279 . 0
4 .10
-2.80
99.00
o
o
CO
CO
CO
1
3
6.1
1
279 . 0
4 .10
-3 . 90
99.00
o
o
CO
CO
CO
1
4
6.1
1
290.0
5 .10
-5 .00
99.00
o
o
CO
CO
CO
1
5
6.1
1
290 . 0
5.70
-5 . 60
99.00
o
o
CO
CO
CO
1
6
6.1
1
295 . 0
2 . 60
-5 . 60
99.00
o
o
CO
CO
CO
1
7
6.1
1
286.0
5 .10
-6 .10
99.00
o
o
CO
CO
CO
1
8
6.1
1
315 . 0
4 .10
-5 . 60
99.00
o
o
CO
CO
CO
1
9
6.1
1
273 . 0
7.20
-5 .00
99.00
o
o
CO
CO
CO
1
10
6.1
1
297 . 0
8 .20
-5 .00
99.00
o
o
CO
CO
CO
1
11
6.1
1
297 . 0
7.70
-4 . 40
99.00
o
o
CO
CO
CO
1
12
6.1
1
268.0
8.80
- .
99.00
o
o
CO
CO
CO
1
13
6.1
1
271. 0
9.30
- . ¦
99.00
o
o
CO
CO
CO
1
14
6.1
1
306.0
7.20
9 9.00
o
o
CO
CO
CO
1
15
6.1
1
256 . 0
9.30
- .
99.00
o
o
CO
CO
CO
1
16
6.1
1
268 . 0
- .
99.00
o
o
CO
CO
CO
1
17
6.1
1
270 . 0
8.80
- . ¦
9 9.00
o
o
CO
CO
CO
1
18
6.1
1
266.0
8.80
-7.20
99.00
o
o
CO
CO
CO
1
19
6.1
1
273 . 0
8.80
-7.80
99.00
o
o
CO
CO
CO
1
20
6.1
1
278 . 0
to / u
-8 . 90
y y. uu
99.00
CO
CO
CO
1
21
6.1
1
285 . 0
6.70
- ¦.
99.00
99.00
CO
CO
CO
1
22
6.1
1
2 94.0
4.60
-
99.00
o
o
CO
CO
CO
1
23
6.1
1
2
-
99.00
o
o
CO
CO
CO
1
24
6.1
1
2 0 9.0
2 60
-
99.00
o
o
Figure 4-26. Partial contents of the I'.XOI NWS.PH. file.
4.2 Site-specific example
liuildinu mi the MVS example in Section 4 I. this section will detail the extraction of
site-specific data as well as merger with the NWS surface and upper air data and subsequent
boundary layer calculations
4.2.1 Site-specific data extraction
The site-specific data for this example is a dataset composed of three levels at 10, 50,
and 100 m with the following variables at each level: go (standard deviation of horizontal wind
direction), ow (standard deviation of the w-component of the wind speed), temperature, wind
direction and wind speed. A sample of the site-specific data file, ONSITE.MET is shown in
Figure 4-27. The AERMET control file, ONSITE Sl.INP is shown in Figure 4-28. Based on
the control file READ statements, the order of variables in the site-specific data are day
(OSDY), month (OSMO), year (OSYR), hour (OSHR), height (HTNN), go (SANN), gw
4-33
-------
(SWNN), temperature (TTNN), wind direction (WDNN), and wind speed (WSNN), NN refers
to the height level 01, 02, and 03. Note that in the data file (Figure 4-27) there is a 0 between
the year and height. This column is skipped using the FORMAT statements. The report and
message files are denoted by the keywords REPORT and MESSAGE and the input data,
ONSITE.MET is denoted by the DATA keyword. The QAOUT keyword denotes the output
file and the location is given with the LOCATION keyword. The READ and FORMAT
statements control the reading of the file as described in Section 3 5.3. Non-default missing
values and bounds are given for several variables and the wind speed threshold is 0.3 m/s. No
variables are listed for auditing so the default audits of icmpciauiiv and winds will occur.
1
3
CO
CO
1
0
10
0
48.7 0.110
U 6 4
. ri0
0 .
1
3
88
1
0
50
0
14.7 -99.000
. ;0
2 .00
1
3
88
1
0
100
0
9 .
-L VJ -±
. >0
3.70
1
3
88
2
0
10
0
22 .
27 3.10
0 . 90
1
3
88
2
0
50
0
15.6 -99.000
1.04
3 04. 00
1. 50
1
3
88
2
0
100
0
13.4 0.340
0.74
3 0 8.50
2.50
1
3
88
3
0
- . ¦
276.50
0 . 60
1
3
88
3
0
. ¦ - ¦ ¦.
0.04
ooi n n
1.30
1
3
88
3
0
27.0 u . jyu
-u . lb
319.10
2 .30
1
3
88
4
C
- . 66
199.70
0 . 60
1
3
88
4
C
. ¦ - ¦ ¦.
- .16
99 . 50
0 . 90
1
3
~ ~
- i .76
321.60
1.30
1
O
j
o
-1.36
289.30
1.20
1
o
o
5
.
CO
1
339.30
1. 50
1
o
o
88
5
0
10 0
-1.26
333.20
2 .10
1
o
o
88
6
0
-2.16
254.00
0.80
1
o
o
88
6
ii
i
293.00
1.10
1
o
o
88
6
0
CO
i1
1
301.80
2 .20
1
o
o
ou
7
)
0
43.3 0.170
-2.26
264.30
0 . 90
1
3
88
7
-
.3 -99.000
-1.76
305.20
1.80
1
3
88
7
-
.0 0.470
-2.06
307.70
2 . 90
Figure 4-27. Pari
ill contents of the site-specific data file ONSITE.MET.
4-34
-------
JOB
REPORT
ONSITE SI
REPORT.TXT
MESSAGES
ONSITE SI
MESSAGE.TXT
ONSITE
DATA
ONSITE.MET
QAOUT
ONSITE QAOUT.TXT
XDATES
1988/3/1
TO 1988/3/10
LOCATION
99999 7 4
.0W 41.3N 0
READ 1 OSDY OSMO OSYR OSHR HT01
SA01 SW01
TT01
WD01
WS01
READ 2
HT02
SAO2 SW0 2
TT02
WD02
WS02
READ 3
HT03
SAO3 SW03
TT03
WD0 3
WS03
FORMAT 1
(4(12,IX)
,4X,F5.1,IX,F5
. 1, IX, F7 .
, ' ,
F6.2,
IX, F7.2,IX,F7.2)
FORMAT 2
(16X,
F5.1,IX,FS
, IX, F7.
, ' ,
F£> ?
i- ^ r
IX,F7.2,IX,F7.2)
FORMAT 3
(16X,
F5.1, IX,F5
. 1 , I.X, F7 .
3,IX,
r
" X, F7.2,IX,F7 . 2)
RANGE TT
-30 < 40
-99
RANGE SA
0 <= 95
-99
RANGE WS
0 < 50
-999
RANGE WD
0 <= 360
-999
THRESHOLD
0.3
Figure 4-28. Control file to extract mid QA site-specific data.
To execute AI-RMI-T sUiue I lor this example. the user would type the following at the
command prom |M
aeimel e\e ()\SITI- SI l\P
assuming the control file and ALRM1-T executable are in the same folder. Processing
information w i 11 he u lillen lo the screen, if the user wishes to have that information written to a
text file, the user would type the following at the command prompt:
aermet.exe ONSITI- Sl.INP > onsite_sl.txt
The contents of example_run.txt are shown in Figure 4-29 and show the AERMET
processing. The first line lists the start date and time of the AERMET processing. The next ten
lines notify the user of the extraction dates followed by ten lines denoting each day's data are
being QA'd. The final messages are that AERMET completed successfully followed by the
AERMET processing end date and time.
4-35
-------
START
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
PROCESSING DATE/T
Extracting ons
Extracting ons
Extracting ons
Extracting ons
Extracting ons
Extracting ons
Extracting ons
Extracting ons
Extracting ons
Extracting ons
QA'ing onsite
QA'ing onsite
QA'ing onsite
QA'ing onsite
QA'ing onsite
QA'ing onsite
QA'ing onsite
QA'ing onsite
QA'ing onsite
QA'ing onsite
IME: NOVEMBER 10, 2021 17:09:10 PM
ite data for month/day/year 03/01/1988
ite data for month/day/year 03/02/1988
ite data for month/day/year 03/03/1988
ite data for month/day/year 03/04/1988
ite data for month/day/year 03/05/1988
ite data for month/day/year 03/06/1988
ite data for month/day/year 03/07/1988
ite data for month/day/year 03/08/1988
ite data for month/day/year 03/09/1988
ite data for month/day/year 03/10/1988
data for month/day/year 03/01/1988 LST
data for month/day/year 03/02/1988 LST
data for month/day/year 03/03/1988 LST
data for month/day/year 03/04/1988 LST
data for month/day/year 03/05/1988 LST
data for month/day/year 03/06/1988 LST
data for month/day/year 03/07/1988 LST
data for month/day/year 03/08/1988 LST
data for month/day/year 03/09/1988 LST
data for month/day/year 03/10/1988 LST
LST
LST
LST
LST
LST
LST
LST
LST
LST
LST
AERMET FINISHED SUCCESSFU
END PROCESSING DATE/TIME: NC
)9:10 PM
Figure 4-29. Control file to extract mul QA she-specific data.
Figure 4-301'i^ure 4-3 slums llie processing messages contained in
ONSITE Sl MESSACil- TXT Messages that start with 'W' are warning messages, T are
informational messages. are error messages and "()" are quality assurance messages. The
101 message indicates that stage I is heing processed The first 160 message indicates the start
time of site-specific data extraction and message 163 and 164 indicate the number of extracted
and duplicate oltser\ ations respecli\ ely The second 160 message indicates the end of the
extraction process. Message ()M indicates a wind speed less than the threshold and the
remaining Q61 messages indicate missing variables with the indicated times and levels.
4-36
-------
101
READINP
PROCESSING STAGE 1
ONSITE
160
OS PROC
BEGIN: ONSITE EXTRACTION 20211110
17:09:10
ONSITE
163
OS PROC
NUMBER OF EXTRACTED
OBSERVATIONS:
240
ONSITE
164
OS PROC
NUMBER OF DUPLICATE
OBSERVATIONS:
0
ONSITE
160
OS PROC
END: ONSITE
EXTRACTION 20211110 13
: 00:03
ONSITE
Q64
CHECK WIND
19880307
HR
02
WIND
SPEED <
0.3 0 LEVEL 2
ONSITE
Q61
AUDIT
19880301
HR
11
TT01
MISSING
LEVEL
1
ONSITE
Q61
AUDIT
19880301
HR
11
WD01
MISSING
LEVEL
1
ONSITE
Q61
AUDIT
19880301
HR
11
WS01
MISSING
LEVEL
1
ONSITE
Q61
AUDIT
19880301
HR
11
TT02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880301
HR
11
WD02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880301
HR
11
WS02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880301
HR
11
TT03
MISSING
LEVEL
3
ONSITE
Q61
AUDIT
19880301
HR
11
WD03
MISSING
LEVEL
3
ONSITE
Q61
AUDIT
19880301
HR
11
WS03
MISSING
LEVEL
3
ONSITE
Q61
AUDIT
19880303
HR
18
TT02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880303
HR
19
TT02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880303
HR
20
TT02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880303
HR
21
TT02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880303
HR
22
TT0 2
MISSING
LEVEL
1
ONSITE
Q61
AUDIT
19880303
HR
23
TT 0 2
MISSING
DID
ONSITE
Q61
AUDIT
19880303
HR
24
TT02
MISSING
LE
ONSITE
Q61
AUDIT
19880304
HR
1
TT02
MISSING
LE'
ONSITE
Q61
AUDIT
19880304
HR
2
TT02
MISSING
LEvll
ONSITE
Q61
AUDIT
19880304
HR
3
TT02
MISSING
LEVEL
z
ONSITE
Q61
AUDIT
19880304
HR
4
TT02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880304
HR
5
TT02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880304
HR
TT02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880304
HR
7
TT02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880
TT02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880
mm n o
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
1988030
MISSING
LEVEL
2
ONSITE
Q61
AUbl'l
1988030
MISSING
LEVEL
2
ONSITE
Q61
AUbl'l
19880304
MISSING
LEVEL
ONSITE
Q61
AUD.I T
19880304
"LID"
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880304
"LID"
MISSING
LEVEL
2
ONSITE
Q61
A HI >TT
19880304
HR
16
TT02
MISSING
LEVEL
2
ONSITE
Q61
ADULT
19880304
HR
17
TT02
MISSING
2
ONSITE
Q61
ADDTT
19880304
HR
18
TT02
MISSING
LEVEL
2
ONSITE
Q61
ADD1 T
i QRsmnzi
HR
19
TT02
MISSING
LEVEL
2
ONSITE
. -.
ADMIT
R
20
TT02
MISSING
LEVEL
2
ONSITE
audit
R
21
TT02
MISSING
LEVEL
2
ONSITK
J 1. i 1 1 L
*
22
TT02
MISSING
LEVEL
2
ONSI "
ILjIT
R
23
TT02
MISSING
LEVEL
2
ONSI
Q61
AUD1.T
R
24
TT02
MISSING
LEVEL
2
ONSITK
...
AUDIT
R
1
TT02
MISSING
LEVEL
2
ONSITK
AUDIT
1988030b
HR
::
TT02
MISSING
LEVEL
2
ONSITE
AUDIT
19880305
HR
3
TT02
MISSING
LEVEL
2
ONSITE
AUDIT
19880305
HR
4
TT02
MISSING
LEVEL
2
ONSITE
AUDIT
80305
HR
5
TT02
MISSING
LEVEL
2
ONSITE
AUDIT
80305
HR
6
TT02
MISSING
LEVEL
2
ONSITE
Q61
305
HR
7
TT02
MISSING
LEVEL
2
ONSITE
Q61
305
HR
8
TT02
MISSING
LEVEL
2
ONSITE
Q61
307
HR
2
WD02
MISSING
LEVEL
2
ONSITE
Q61
307
HR
16
WD01
MISSING
LEVEL
1
ONSITE
Q61
AD
19880307
HR
16
WS01
MISSING
LEVEL
1
ONSITE
Q61
AD
19880307
HR
17
WD01
MISSING
LEVEL
1
ONSITE
Q61
AUDIT
19880307
HR
17
WS01
MISSING
LEVEL
1
ONSITE
Q61
AUDIT
19880308
HR
10
TT01
MISSING
LEVEL
1
ONSITE
Q61
AUDIT
19880308
HR
10
WD01
MISSING
LEVEL
1
ONSITE
Q61
AUDIT
19880308
HR
10
WS01
MISSING
LEVEL
1
ONSITE
Q61
AUDIT
19880308
HR
10
TT02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880308
HR
10
WD02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880308
HR
10
WS02
MISSING
LEVEL
2
ONSITE
Q61
AUDIT
19880308
HR
10
TT03
MISSING
LEVEL
3
ONSITE
Q61
AUDIT
19880308
HR
10
WD03
MISSING
LEVEL
3
ONSITE
Q61
AUDIT
19880308
HR
10
WS03
MISSING
LEVEL
3
Figure 4-30. Contents of the ONSITE_Sl_MESSAGE.TXT message file.
4-37
-------
Figure 4-31 through Figure 4-33 show the contents of the report file,
ONSITE_Sl_REPORT.TXT. Figure 4-31 is analogous to Figure 4-4 and Figure 4-11, showing
the input information. Figure 4-32 shows the QA summary of the site-specific data and has a
missing value and bounds summary like Figure 4-5 and Figure 4-13. Since there is more than
one level of data, the QA summary is by level. Most of the data are accepted and there was only
one wind speed less than the threshold. Finally, Figure 4-33 shows the message summary for
the site-specific data extraction. There were no error or warning messages and five information
messages distributed among 101,160,163, and 164. There were (->3 QA messages with 62 of
those associated with Q61 and one for Q64.
4-38
-------
AERMET VERSION 21DRF
START PROCESSING DATE/TIME: NOVEMBER 10, 2021 17:09:10 PM
RUNSTREAM CONTROL FILE: ONSITE Sl.INP
**************************** INPUT SUMMARY ****************************
AERMET SETUP SUCCESSFUL
PROCESSING STAGES 1
1. JOB FILE NAMES
MESSAGES OPEN ONSITE SI MESSAGE.TXT
REPORT OPEN ONSITE SI REPORT.RPT
DEBUG NO FILE
2. UPPERAIR DATA
NO PROCESSING REQUESTED
3. SURFACE DATA
NO PROCESSING REQ1
4 .
PRC :
SI LONGITUDE TIME ADJUSTMENT
ELEVATION
LOCATION: 999 . -74.00 0
o
o
o
DATA FIL :
QAOUT FI : QAOUT.TXT
NUMBER OF OBSI :
THRESHOLD WIND SP : .30
5. PROG DATA
NO PROCESSING REQUESTED
6. METPREP DATA
NO PROCESSING REQUESTED
Figure 4-31. Input summary contents of the ONSITE extraction report file.
4-39
-------
********************
******** QA SIJMMARY
*********************
*******
ONSITE DATA
VARIABLE MISSING
VALUE LOWER BOUND
UPPER BOUND
TT -99.00
<= -30.
00
>= 4 0.00
WD -999.00
<0.00
> 360.00
WS -999.00
A
II
o
o
o
>= 50.00
HOURLY VALUES
LEVEL
VARIABLE
#
#
UPPER
%
OBS
MISSING
BOUND
ACCEPTED
10.000 M
TT
240
2
0
99
17
WD
240
4
0
98
33
WS
240
4
0
98
33
50.000 M
TT
240
0
82
92
WD
240
n
98
75
WS
240
u
99
17
100.000 M
TT
240
0
99
17
WD
240
0
99
17
WS
240
0
99
17
WIND AND TEMPERATURE CHECKS (IF .
)
NUMBER OF OBS:
1 CALM WINDS (
< THRESHOLD)
0 NO INPUT WD
WITH WS
0 NO INPUT WD
WITH WS
Figure 4-32. QA siiininnry contents of the ONSITK extraction report file.
4-40
-------
MESSAGE SUMMARY
ERROR MESSAGES 0 MESSAGES
WARNING MESSAGES 0 MESSAGES
INFORMATION MESSAGES 5 MESSAGES
101: 1
160: 2
163: 1
164: 1
QA MESSAGES 63 MESSAGES
Q61: 62
Q64: 1
AERMET FINISHED SUCCESSFULLY
END PROCESSING DATE/TIME: NOVEMBER 10, 2021 17:09:10 PM
Figure 4-33. Message summary contents of the ONSITE extraction report file.
Figure 4-34 slums ihe OAOl'T file. ONSITI- OA.OUT. The header has similar
infornnilion as the SI RI'ACI- and I 'PPI-RAIR OAOl T files shown in Figure 4-7 and Figure
4-17, respecli\ ely Also, the ONSITI- OAOLT file will include the threshold wind speed, an
over land or o\ er water identifier and modified missing values or bounds for the variables. Also
included are the first and last le\ els for multi-level variables. In this example, all variables are
on all three levels I-'or descriptions of the variable names see Table B-3 and Table B-4 in
Appendix B.
4-41
-------
AERMET VERSION 21DRF
LOCATION 999 99
41.
3 0 ON
74.000W 0
FILE TYPE:
QAOUT
THRESHOLD
0.300
OVERLAND
DATES 1988
03 01
1988
03 10
RANGE SANN
0
<=
95
-99
RANGE TTNN
-30
<
40
-99
RANGE WDNN
0
<=
360
-999
RANGE WSNN
0
<
50
-999
HTNN FIRST
-LAST
LEVELS
1
3
SANN FIRST
-LAST
LEVELS
1
3
SWNN FIRST
-LAST
LEVELS
1
3
TTNN FIRST
-LAST
LEVELS
1
3
WDNN FIRST
-LAST
LEVELS
1
3
WSNN FIRST
-LAST
LEVELS
1
3
DATE
HR
LEV
HTNN SANN
SWNN
19880301
01
1
10
0000 48.7000
0.1100
19880301
01
2
5(
-99 .0000
19880301
01
3
10 (
0 . 4100
19880301
02
1
1(
0 .0800
19880301
02
2
5 (
-99 .0000
19880301
02
3
10 (
0 .3400
19880301
03
1
i n
.0800
19880301
03
.0000
19880301
03
" .3900
19880301
04
0 . 0400
19880301
04
50
-99.0000
19880301
04
100
0000 55.1000
0 . 4500
19880301
05
10
0000 Ij.jOUu
0.1300
19880301
05
_
'¦0
0000 29.4000
-99 .0000
19880301
05
3
'0
0000 29.8000
0.4700
Figure 4-34. Partial contents of the ONSITK QAOUT file.
4-42
TTNN
0.6400
317
1.8400
323
1.6400
320
. '40 0
273
. '400
304
0 .7400
308
-0 .7600
276
0.0400
331
-0.1600
319
-1. 6600
199
-0 .7600
99
-0 .7600
321
-1.3600
289
-0.8600
339
-1.2600
333
WSNN
0.8000
2.0000
3.7000
0.9000
1.5000
2 .5000
0.6000
1.3000
2.3000
0.6000
0.9000
1.3000
1.2000
1.5000
2.1000
WDNN
5000
3000
5000
1000
0000
5000
5000
7000
1000
7000
5000
6000
3000
3000
2000
-------
4.2.2 Data merge and boundary layer calculations
After extracting the site-specific data, the next step is to merge the site-specific with the
surface data and upper air data extracted as part of the example discussed in Section 4.1. The
AERMET stage 2 control file, ONSITE S2.INP is shown in Figure 4-35. The QAOUT files
from the upper air and surface extractions discussed in 4.1 are shown in the UPPERAIR and
SURFACE pathways. The site-specific QAOUT data arc show n in the ONSITE pathway. The
METPREP pathway lists the two output files, ONSITi; NWS SIC and ONSITE NWS.PFL.
The LOCATION keyword gives the location of the modeled source and options include NWS
substitution and randomization of the wind directions. The NWS anemometer height is listed as
6.1 m. Since surface data are from two sources, llie site-specific location and the NWS station,
two sets of surface characteristics are listed. The site-specific characteristics are denoted by
FREQ SECT, SECTOR, and SITE CHAR and are monthly lor two sectors. The NWS station
surface characteristics are denoted by IRIX.) SECT2, SIXTOR2, and SITE CHAR2 and are
the same as shown in the example discussed in Section 4 I 3
To execute Al-RMI-T stage 2 for this example, the user would type the following at the
command prompt:
acimcl.exe ONSITI- S2 INP
assuming the control file and AI-RMI-T executable are in the same folder. Processing
information will he w litten to the screen. If the user wishes to have that information written to a
text file, the user would type the following at the command prompt:
aermet.exe ONS1TE S2.INP > onsite_s2.txt
The contents of onsite_s2.txt are shown in Figure 4-36 and show the AERMET
processing. The first line lists the start date and time of the AERMET processing. The next ten
lines notify the user of the upper air extraction dates followed by ten lines denoting surface
extraction dates. The next ten lines denote that initial data assignments for variables such as
wind and temperature and the next ten lines denote PBL calculations are being done. The final
4-43
-------
messages are that AERMET completed successfully followed by the AERMET processing end
date and time.
Figure 4-37 through Figure 4-39 show partial contents of the
ONSITE_2_MESSAGE.TXT file. Figure 4-37 shows extraction messages for the upper air,
surface, and site-specific data. The messages for the upper air and surface extraction are the
same as shown in Figure 4-20 in Section 4.1.3. Messages T60 llirough 164 and the second 160
message denote the site-specific extraction. Message I7t) indicates the beginning of PBL
calculations and 182 indicates that the solar angle method will he used to determine stability. In
Figure 4-38, message 173 occurs throughout the IMil. calculations, indicating that the
measurement height of 10 m from the site-specific data is less than 2" limes the surface
roughness of 0.75. This is pointed out to indicate that AERMET is using the site-specific
characteristics when site-specific data are available. I 'iuin e 4-3^ shows messages about
sounding information and note that message 190 indicates that NWS data are substituted for
March 3, 1988 hour 10.
4-44
-------
JOB
REPORT
ONSITE
S2 REPORT.RPT
MESSAGES
ONSITE
S2 MESSAGE.TXT
UPPERAIR
QAOUT
UPPER
QAOUT.TXT
SURFACE
QAOUT
SURFACE QAOUT
.TXT
ONSITE
QAOUT
ONSITE
QAOUT.
TXT
METPREP
OUTPUT
ONSITE
NWS.SFC
PROFILE
ONSITE
NWS.PFL
LOCATION
MYSITE
74.00W
41.3N 5
METHOD
REFLEVEL SUBNWS
METHOD
WIND DIR RANDOM
NWS HGT
WIND
6.1
FREQ SECT
MONTHLY 2
SECTOR 1
35
225
SECTOR 2
225
35
SITE CH7
SITE CH7
SITE CH7
SITE CH7
SITE CHAI
SITE CHAI
SITE CHAR
SITE CHAR
SITE CHAR
SITE CHAR
SITE CHAR
11 1
0. 600
0.500
SITE CHAR
12 1
. 0
0.300
SITE
1 2
u . 5 0 0
1. 3U0
0.750
SITE
2 2
i .
1.500
0.750
SITE CHAR
3 2
0.500
1.500
0.750
SITE CH7
4 2
0.700
1. 000
SITE CH7
5 2
0.700
1. 000
SITE CHAR
6 2
_ . _
0.300
1.500
SITE CHAR
7 z.
u. 150
0.300
1.500
SITE CHAR
8 2
0. 150
0.300
1.500
SITE CHAR
9 2
0.200
1. 000
1.250
SITE CHAR
10 2
0.200
1. 000
1.250
SITE CHAR
11 2
0.200
1. 000
1.250
SITE CHAR
12 2
0.500
1.500
0.750
FREQ SECT2
ANNUAL
1
SECTOR2
1 0
360
SITE CHAR2
110
.15 2.
O
o
I1
ro
Figure 4-35. Control file for boundary layer calculations in METPREP.
4-45
-------
START
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
Stage
PROCESSING DATE/TIME: NOVEMBER 10, 2021 17:09:32 PM
Extracting upper air data for month/day/year 03/01/1988 LST
Extracting upper air data for month/day/year 03/02/1988 LST
Extracting upper air data for month/day/year 03/03/1988 LST
Extracting upper air data for month/day/year 03/04/1988 LST
Extracting upper air data for month/day/year 03/05/1988 LST
Extracting upper air data for month/day/year 03/06/1988 LST
Extracting upper air data for month/day/year 03/07/1988 LST
Extracting upper air data for month/day/year 03/08/1988 LST
Extracting upper air data for month/day/year 03/09/1988 LST
Extracting upper air data for month/day/year 03/10/1988 LST
Extracting surface data for month/day/year 03/01/1988 LST
Extracting surface data for month/day/year 03/02/1988 LST
Extracting surface data for month/day/year 03/03/1988 LST
Extracting surface data for month/day/year 03/04/1988 LST
Extracting surface data for month/day/year 03/05/1988 LST
Extracting surface data for month/day/year 03/06/1988 LST
Extracting surface data for month/day/year 03/07/1988 LST
Extracting surface data for month/day/year 03/08/1988 LST
Extracting surface data for month/day/year 03/09/1988 LST
Extracting surface data for month/day/year 03/10/1988 LST
Extracting onsite data for month/day/year 03/01/1988 LST
Extracting onsite data for month/day/year 03/02/1988 LST
Extracting onsite data for month/day/year 03/03/1988 LST
Extracting onsite data for month/day/year 03/04/1988 LST
Extracting onsite data for month/day/year 03/05/1988 LST
Extracting onsite data for month/day/year 03/06/1988 LST
Extracting onsite data for month/day/year 03/07/1988 LST
Extracting onsite data for month/day/year 03/08/1988 LST
Extracting onsite data for month/day/year 03/09/1988 LST
Extracting onsite data for month/day/year 03/10/1988 LST
Initial data assignments for month/day/year 03/01/1988 LST
Initial data assignments for month/day/year 03/02/1988 LST
Initial data assignments for month/day/year 03/03/1988 LST
Initial data assignments for month/day/year 03/04/1988 LST
Initial data assignments for month/day/year 03/05/1988 LST
Initial data assignments for month/day/year 03/06/1988 LST
Initial data assignments for month/day/year 03/07/1988 LST
Initial data assignments for month/day/year 03/08/1988 LST
Initial data assignments for month/day/year 03/09/1988 LST
Initial data assignments for month/day/year 03/10/1988 LST
PBL calculations for month/day/year 03/01/1988 LST
PBL calculations for month/day/year 03/02/1988 LST
PBL calculations for month/day/year 03/03/1988 LST
PBL calculations for month/day/year 03/04/1988 LST
PBL calculations for month/day/year 03/05/1988 LST
PBL calculations for month/day/year 03/06/1988 LST
PBL calculations for month/day/year 03/07/1988 LST
PBL calculations for month/day/year 03/08/1988 LST
PBL calculations for month/day/year 03/09/1988 LST
PBL calculations for month/day/year 03/10/1988 LST
AERMET FINISHED SUCCESSFULLY
END PROCESSING DATE/TIME: NOVEMBER 10, 2021 17:09:33 PM
Figure 4-36. Processing steps for the boundary layer calculations
4-46
-------
101
READINP
PROCESSING
STAGE 2
UPPERAIR
W01
GETLOC
STATION
ELEVATION NOT NEEDED
METPREP
W7 0
PBL TEST
LOCATION KEYWORD NOT
NEEDED
UPPERAIR
120
UP PROC
UPPER AIR
EXTRACTION
BEGIN
20211110 17:
09:33
UPPERAIR
123
UP PROC
NUMBER
OF
EXTRACTED
SOUNDINGS: 2 0
UPPERAIR
124
UP PROC
NUMBER
OF
UNIQUE VALID SOUNDINGS: 2 0
UPPERAIR
125
UP PROC
NUMBER
OF
DUPLICATE
SOUNDINGS: n
UPPERAIR
126
UP PROC
NUMBER
OF
SKIPPED SOUNDINGS
: o
UPPERAIR
120
UP PROC
UPPER AIR
EXTRACTION
END 20211110 17 OS
: 33
SURFACE
140
SF PROC
SURFACE
EXTRACTION BEGIN: 20211110 17:09:33
SURFACE
W4 5
CHECK ASOS
STATION
IS
ASOS, BUT
BEFORE
COMMISSION
DATE
1995
TE
19880301
SURFACE
W4 5
CHECK ASOS
STATION
IS
ASOS, BUT
BEFORE
COMMISSION
DATE
19950801
TE
19880302
SURFACE
W4 5
CHECK ASOS
STATION
IS
ASOS, BUT
BEFORE
COMMISSION
DATE
19950801
19880303
SURFACE
W4 5
CHECK ASOS
STATION
IS
ASOS, BUT
BEFORE
COMMISSION
DATE
19950801
FOR
19880304
SURFACE
W4 5
CHECK ASOS
STATION
IS
ASOS, BUT
BEFORE
COMMISSION
DATE
1
L
FOR
19880305
SURFACE
W4 5
CHECK ASOS
STATION
IS
ASOS, BUT
BEFORE
COMMISSION
DATE
1
L
FOR
19880306
SURFACE
W4 5
CHECK ASOS
STATION
IS
ASOS, BUT
BEFORE
COMMISSION
DATE
]
1
FOR
307
SURFACE
W4 5
CHECK ASOS
STATION
IS
ASOS, BUT
BEFORE
COMMISSION
DATE
]
L
FOR
DATE
308
SURFACE
W4 5
CHECK ASOS
STATION
IS
ASOS, BUT
BE
ISSION
DATE
]
FOR
DATE
___309
SURFACE
W4 5
CHECK ASOS
STATION
IS
ASOS, BUT
be;
ISSION
DATE
1
FOR
DATE
19880310
SURFACE
146
SF PROC
NUMBER
OF
EXTRACTED
SUR
RVATIONS:
240
SURFACE
147
SF PROC
NUMBER
OF
RETAINED OBSE
: :M()
SURFACE
140
SF PROC
SURFACE
EXTRACTION END:
i» .1 7 : 0 0 :
33
ONSITE
160
OS PROC
BEGIN:
ONS
ITE EXTRAC
TTO
110 17:0r
. i i
ONSITE
163
OS PROC
NUMBER
NS:
ONSITE
164
OS PROC
NUMBER
iuNS:
ONSITE
160
OS PROC
END: ON
110 1.7 :()<¦¦);
METPREP
170
PBL PROC
PBL C
METPREP
183
PBL PROC
SOLAR /\
HI LITY
DETERMINATION
Figure 4-37. Initial contents of the stage 2 message file ONSITK_S2_MESSAGE.TXT
4-47
-------
METPREP
173
WINDS
DATE
19880301
HR
01
WIND
HEIGHT
10
00
C 2 OX
zo
0
75
METPREP
173
WINDS
DATE
19880301
HR
02
WIND
HEIGHT
10
00
C 2 OX
zo
0
75
METPREP
173
WINDS
DATE
19880301
HR
03
WIND
HEIGHT
10
00
C 2 OX
zo
0
75
METPREP
173
WINDS
DATE
19880301
HR
05
WIND
HEIGHT
10
00
C 2 OX
zo
0
75
METPREP
173
WINDS
DATE
19880301
HR
06
WIND
HEIGHT
10
0 0 <
- "¦> n v
7 n
o
7 5
METPREP
173
WINDS
DATE
19880301
HR
07
WIND
HEIGHT
10
METPREP
173
WINDS
DATE
19880301
HR
08
WIND
HEIGHT
10
METPREP
173
WINDS
DATE
19880301
HR
09
WIND
HEIGHT
10
METPREP
173
WINDS
DATE
19880301
HR
10
WIND
HEIGHT
10
METPREP
173
WINDS
DATE
19880301
HR
12
WIND
HEIGHT
10
METPREP
173
WINDS
DATE
19880301
HR
13
WIND
HEIGHT
METPREP
173
WINDS
DATE
19880301
HR
14
WIND
HEIGHT
METPREP
173
WINDS
DATE
19880301
HR
15
WIND
HEIGHT
20X
ZO
0
METPREP
173
WINDS
DATE
19880301
HR
16
WIND
HEIGHT
"o X
zo
0
7
METPREP
173
WINDS
DATE
19880301
HR
17
WIND
heig:
2 OX
zo
0
7
METPREP
173
WINDS
DATE
19880301
HR
18
WIND
heig:
2 OX
zo
0
75
METPREP
173
WINDS
DATE
19880301
HR
19
WIND
heig:
:o>
75
METPREP
173
WINDS
DATE
19880301
HR
20
WIND
heig:__
75
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
METPREP
173
WINDS
DATE
Figure 4-38. Partial contents ol'llie stage 2 message file ONSITE_S2_MESSAGE.TXT
4-48
-------
METPREP
177
READ
SOUND
SOUNDING FOR DATE
19880301 IS
19880301 HR 07
SOUNDING
#
1
METPREP
W7 6
READ
"sound
DATE 19880301 TOP
OF SOUNDING
5.2 KM EXTENDS
BEYOND 5
. 0
KM;
SOUNDING
NOT
EXTENDED
ONSITE
190
PROFILE
NWS DATA SUBSTITUTED FOR ONSITE
DATA FOR DATE
19880301
HR 11
METPREP
177
READ
SOUND
SOUNDING FOR DATE
19880302 IS
19880302 HR 07
SOUNDING
#
1
METPREP
W7 6
READ
"sound
DATE 19880302 TOP
OF SOUNDING
5.4 KM EXTENDS
BEYOND 5
. 0
KM;
SOUNDING
NOT
EXTENDED
METPREP
177
READ
"sound
SOUNDING FOR DATE
19880303 IS
19880303 HR 07
SOUNDING
ft
1
METPREP
W7 6
READ
"sound
DATE 19880303 TOP
OF SOUNDING
5.4 KM EXTENDS
¦ND 5
. 0
KM;
SOUNDING
NOT
EXTENDED
METPREP
177
READ
"sound
SOUNDING FOR DATE
19880304 IS
19880304 HR 0^
"DING
ft
1
METPREP
W7 6
READ
"sound
DATE 19880304 TOP
OF SOUNDING
5. 4 KM EXTENDS'
ND 5
. 0
KM;
SOUNDING
NOT
EXTENDED
METPREP
177
READ
"sound
SOUNDING FOR DATE
19880305 IS
19880305 HR 07
SOUNDING
1
METPREP
W7 6
READ
"sound
DATE 19880305 TOP
OF SOUNDING
5.4 KM EXTENDS
BEYOND
KM;
SOUNDING
NOT
EXTENDED
METPREP
177
READ
"sound
SOUNDING FOR DATE
19880306 IS
19880306 HR 07
SOUNDI
1
METPREP
W7 6
READ
"sound
DATE 19880306 TOP
OF SOUNDING
5.4 KM EXTENDS
BEYONE
SOUNDING
NOT
EXTENDED
METPREP
177
READ
"sound
SOUNDING FOR DATE
19880307 IS
19880307 HR 07
SOUNDING
METPREP
W7 6
READ
"sound
DATE 19880307 TOP
OF SOUNDING
5.4 KM EXTENDS
BEYOND 5
JNDING
NOT
EXTENDED
METPREP
177
READ
"sound
SOUNDING FOR DATE
19880308 IS
19880308 HR 07
NG
#
1
METPREP
W7 6
READ
"sound
DATE 19880308 TOP
OF SOUNDING
5.5 KM EXTENDS
"¦) 5
. 0
KM;
NG
NOT
EXTENDED
ONSITE
190
PROFILE
NWS DATA SUBSTITUTED FOR ONSITE
DATA FOR DATE
_ _'308
HR 10
METPREP
177
READ
SOUND
SOUNDING FOR DATE
1988 IS
19880309 H
NG
#
1
METPREP
W7 6
READ
"sound
DATE 19880309 TOP
OF SO -
^.5 KM EXT
) 5
. 0
KM;
SOUNDING
NOT
EXTENDED
METPREP
177
READ
"sound
SOUNDING FOR DATE
198n
9880310 Hxv w ,
NG
#
1
METPREP
W7 6
READ
"sound
DATE 19880310 TOP
OF So
. n tcm EXTENDS
BEYOND 5
. 0
KM;
SOUNDING
NOT
EXTENDED
Figure 4-39. Final contents of the stage 2 message file ()\SNT._S2_IV1ESSA(;K.T\T
4-49
-------
Figure 4-40 through Figure 4-43 show the contents of the report file,
ONSITE_S2_REPORT.TXT. Figure 4-40 is similar to Figure 4-4, Figure 4-11, and Figure
4-3 lin that it shows the summary files and locations of the upper air and surface stations and
site-specific tower location. Figure 4-41 shows the summary for the METPREP pathway,
including processing dates, site location (even though not needed), the output filenames and
processing options. For this example, wind directions are randomized, and cloud substitution is
performed. However, temperature substitution is not performed since cloud cover is being
substituted. Following the METPREP summary is the surface characteristics summary in
Figure 4-42 where the surface characteristics for each processed year are shown for both the
primary (site-specific tower) and secondary (MVS station) locations I'or this example, only
one year is processed. Finally, in Figure 4-43 is the message file summary; like Figure 4-24.
For the boundary layer calculations there were no error messages, 22 warning messages
distributed among W01, W45, W70. and W76, 211 information messages distributed among
several message types and no qualily assurance messages I 'inally, the report file notifies the
user AERMET finished successfully with the date and time of program execution.
Figure 4-44 and I'igure 4-45 show the contents of the two output files,
ONSITE NWS.SF(' and ONSITi; WVS PI I. respectix ely. The user is referred to Table C-4
and Table C-5 in Appendix ('. Section (' 2 I'or the formats. Note that the data in the surface file
shown in l-'iuure 4-44 is a mix of site-sped lie (Y\I)-()S) and NWS (NAD-SFC) data. For the
profile data shown in I'igure 4-45 the three levels of temperature, wind, and turbulence data
from the site-specific data are e\ ident
4-50
-------
AERMET VERSION 21DRF
START PROCESSING DATE/TIME: NOVEMBER 10, 2021 17:09:32 PM
RUNSTREAM CONTROL FILE: ONSITE S2.INP
**************************** INPUT SUMMARY ****************************
AERMET SETUP SUCCESSFUL
PROCESSING STAGES 2
1. JOB FILE NAMES
MESSAGES OPEN ONSITE S2 MESSAGE.TXT
REPORT OPEN ONSITE S2 REPORT.RPT
DEBUG NO FILE
2. UPPERAIR DATA
PROCESSING DATES: 03/01/1988 - 03/10/1988
SITE ID LATITUDE LONGI" : ADJUSTMENT
LOCATION: 00014735 42.75 -71
DATA FILE: NO FILENAME INPUT
EXTRACT FILE: NO FILENAME INPUT
QAOUT FILE: OPEN UPPER QAOU^ '
UPPER AIR DATA ABOVE 5000 NOT EXTRAC'
UPPER AIR AUTOMATIC DATA CHECKS ARE: ___
3. SURFACE DATA
PROCESSING DATES: '
SITE L :me ADJUSTM
_LEVATION
LOC. 1.47oj 0
CO
CO
CO
o
ASO VIM I.KSION DATE: 19950801
DAT. : ^O FILENAME INPUT
ASO \| KILE: NO FILENAME INPUT
EXT : jENAME IN
QAO : -J SU
4. ONSITE DAta
PROCESSING DATES, w. !8
£ LONGITUDE TIME ADJUSTMENT
ELEVATION
LOCATION: 99999 41.30 -74.00 0
o
o
o
DATA FILE: NO FILENAME INPUT
QAOUT FILE: OPEN ONSITE QAOUT.TXT
NUMBER OF OBSERVATIONS/HOUR: 1
5. PROG DATA
NO PROCESSING REQUESTED
Figure 4-40. Input summary contents of ONSITE_S2_REPORT.TXT
4-51
-------
6. METPREP DATA
PROCESSING DATES
: 03/01/1988 - 03/10/1988
SITE
ID LATITUDE LONGITUDE
TIME ADJUSTMENT
LOCATION:
-9 41.30 -74.00
5
OUTPUT FILE:
PROFILE FILE:
OPEN
OPEN
ONSITE NWS.SFC
ONSITE NWS.PFL
METPREP PROCESSING OPTIONS
PROCESS OPTION DESCRIPTION
WIND DIRECTION
REFLEVEL
CLOUD COVER
TEMPERATURE
RANDOM WIND DIRECTIONS A
SUB NWS NWS WINDS AND TEM
SUB CC CLOUD COVER SUBST
NOTSUB TEMPERATURE NOT S
CD
) FOR MISSING ONSITE DATA
Figure 4-41. METPREP summary contents of ONSITK_S2_UKPORT.TXT
4-52
-------
******
**********************
SFC
CHARACTERISTICS
SUMMARY *
********
*********
**********
PRIMARY SITE CHARACTERISTICS
YEAR:
198 8 FREQUENCY
MONTHLY
NUMBER OF
SECTORS:
2
YEAR
MONTH
BEGIN SECTOR
END SECTOR
ALBEDO
BOWEN
RATIO
ROUGHNESS
LENGTH
(M)
1988
JANUARY
35.
225.
0
35
0
80
0
3000
1988
JANUARY
225.
35.
0
50
1
50
0
7500
1988
FEBRUARY
35.
225.
0
35
0
80
0
3000
1988
FEBRUARY
225.
35.
0
50
1
50
0
7500
1988
MARCH
35.
225.
0
35
0
80
0
3000
1988
MARCH
225.
35.
0
1
50
0
7500
1988
APRIL
35.
225.
0
0
40
0
5000
1988
APRIL
225.
35.
0
0
70
1
0000
1988
MAY
35.
225.
0
0
40
0
5000
1988
MAY
225.
35.
3
1
0000
1988
JUNE
35.
225.
1
0
7000
1988
JUNE
225.
35.
1
5000
1988
JULY
35.
225.
0
7000
1988
JULY
225.
35.
1
5000
1988
AUGUST
35.
225.
u
12
u
0
7000
1988
AUGUST
225.
35.
0
15
0
j i
1
5000
1988
SEPTEMBER
35.
225.
0
20
0
6(
5000
1988
SEPTEMBER
225.
35.
1
00
2500
1988
OCTOBER
35.
225.
0
60
5000
1988
OCTOBER
225.
1
00
2500
1988
NOVEMBER
35.
0
60
yj
5000
1988
NOVEMBER
225.
1
00
l
2500
1988
DECEMBER
35.
0
0
3000
1988
DECEMBER
225.
¦ 0
0
7500
SECONDARY SITE CH.
YEAR:
198 8 FREQUEN
NUMBER
YEAR
ST'REDO
^N
RATIO
ROUGHNESS
LENGTH
(M)
1988
>
2
00
0
1200
Figure 4-42. SuiTsico chnnulcrislics siimmiirv contents of ONSITE_S2_REPORT.TXT
4-53
-------
****** MESSAGE SUMMARY ****************************
ERROR MESSAGES
0 MESSAGES
WARNING MESSAGES
22 MESSAGES
W01
1
W4 5
10
W7 0
1
W7 6
10
INFORMATION MESSAGES
211 MESSAGES
101
1
120
2
123
1
124
1
125
1
126
1
140
2
146
1
147
1
160
2
163
1
164
1
170
1
173
182
177
10
183
1
190
2
QA MESSAGES
AEF
ENI
: . : : >M
Figure 4-43. Message siiiiiinsirv contents of 0\SITK_S2_REP0RT.TXT
4-54
-------
41
3 0 ON
74
000
UA
ID:
00014735 SF
ID:
14735 OS
ID: 99999
VERSION
21DRF
CCVR Sub
88
3
61
-2.7
0
062
-9
"ooo
-9
000
-999.
37
7.9
0.7500
1.50
1.00
0
80
317.5
10.0
273
8
10
0
0
-9
00
999.
1003.
4
NAD-OS
NoSubs
88
3
61
2
-3.5
0
069
-9
000
-9
000
-999.
44
8.5
0.7500
1.50
1.00
0
90
273.1
10.0
273
5
10
0
0
-9
00
999.
1003.
1
NAD-OS
NoSubs
88
3
61
3
-1.6
0
046
-9
000
-9
000
-999.
24
5.7
0.7500
1.50
1.00
0
60
276.5
10.0
272
4
10
0
0
-9
00
999.
1003.
1
NAD-OS
NoSubs
88
3
61
-1.0
0
034
-9
000
-9
000
-999.
15
3.6
0.3000
0.80
1.00
0
60
199.7
10.0
271
5
10
0
0
-9
00
999.
1003.
1
NAD-OS
NoSubs
88
3
61
5
-6.3
0
093
-9
000
-9
000
-999.
68
11.3
0.7500
1.50
1.00
l
20
289.3
10.0
271
8
10
0
0
-9
00
999.
1003.
0
NAD-OS
NoSubs
88
3
61
6
-2.8
0
062
-9
000
-9
000
-999.
37
7.5
0.7500
1.50
1.00
0
80
0
10
0
0
-9
00
999.
1004 .
0
NAD-OS
NoSubs
88
3
61
7
-3.6
0
069
-9
000
-9
000
-999.
44
8.5
0.7500
1.50
1.00
0
90
)
9
10
0
0
-9
00
999.
1004 .
0
NAD-OS
NoSubs
88
3
61
-5.4
0
148
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000
-9
000
-999.
137
54.2
0.7500
1.50
0.67
1
30
8
10
0
0
-9
00
999.
1005.
6
NAD-OS
NoSubs
88
3
61
25.1
0
321
0
558
0
007
248.
437
-118.3
0.7500
1.50
0.56
1
90
10
0
0
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00
999.
1005.
7
NAD-OS
NoSubs
88
3
61
10
60.6
0
396
0
949
0
008
506.
599
-92.0
0.7500
1.50
0.52
2
30
10
0
0
-9
00
999.
1005.
6
NAD-OS
NoSubs
88
3
61
11
88.3
0
793
1
182
0
005
671.
1695
-505.9
0.1200
1.50
0.51
7
2
0
0
-9
00
999.
1005.
2
NAD-SFC
NoSubs
88
3
61
12
97.8
0
438
1
247
0
007
711.
851
-76.9
0.7500
1.50
0.51
2
10
0
0
-9
00
999.
1004 .
0
NAD-OS
NoSubs
88
3
61
13
99.6
0
535
1
277
0
006
749.
939
-137.9
0.7500
1.50
0.51
3
10
0
0
-9
00
999.
1003.
0
NAD-OS
NoSubs
88
3
61
14
88.9
0
533
1
248
0
006
781.
933
-151.8
0.7500
1.50
0. M
10
0
0
-9
00
999.
1002.
0
NAD-OS
NoSubs
88
3
61
15
65.9
0
483
1
147
0
007
818.
808
-152.3
0.7500
1.50
0. V:
0
-9
00
999.
1002.
0
NAD-OS
NoSubs
88
3
61
16
31.5
0
453
0
905
0
007
841.
733
-263.9
0.7500
1.50
O.V.
lO.D
0
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00
999.
1001.
0
NAD-OS
NoSubs
88
3
61
17
-15.1
0
430
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000
-9
000
-999.
678
469.5
0.7500
1.50
0.62
10.0
274
0
-9
00
999.
1001.
0
NAD-OS
NoSubs
88
3
61
18
-15.6
0
147
-9
000
-9
000
-999.
249
18.1
0.7500
1.50
0.86
1
90
J1U. 8
10.0
273
0
-9
00
999.
1001.
0
NAD-OS
NoSubs
88
3
61
19
-11.2
0
124
-9
000
-9
000
-999.
108
15.1
0.7500
1.50
l.iii)
1
60
313.3
10.0
272
0
-9
00
999.
1001.
0
NAD-OS
NoSubs
88
3
61
20
-7.4
0
100
-9
000
-9
000
-999.
76
12.2
0.7500
1.50
l.DD
1
30
326.2
10.0
271
999.
1002.
0
NAD-OS
NoSubs
88
3
61
21
-17.5
0
154
-9
000
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Figure 4-44. Partial contents of ONSITE NWS.SFC
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1
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0.34
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0.74
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0 .34
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Partial contents of ONSITE NWS.PI-1.
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5.0 Technical Notes
This section provides a technical description of the processing methods employed by
AERMET. This includes quality assessment procedures beyond the simple check against upper
and lower bounds, the averaging method used to produce hourly values when site-specific data
contains more than one observation period each hour, and modifications that can be made to
NWS upper air data. More information about the methodology used to calculate the boundary
layer parameters can be found in the AERMOD Model l-'ormulalioii and Evaluation Document
(EPA, 2021a)
5.1 Quality assessment procedures
The main quality assessment procedures arc similar for all types of data. Iiach variable
is checked to see if it is missing (its \ nine matches the missing \ alue code), and if not missing,
the value is checked to see if it is between the lower and upper hounds. Appendix B lists the
variables for each type of data, their units, default bounds and missing value codes. A violation
does not necessarily indicate an error in the data I or example, it could mean the bounds are not
reasonable for a particular time of year or location It is up to the user to determine if the
reported violations constitute errors in the data
I 'or MVS hourly surface observations, several additional checks between variables are
also performed NW S surface data are checked for dew-point temperature exceeding dry-bulb
temperature (DI'TP TMI'D) and having a zero-wind speed (WSPD = 0), indicating calm
conditions, but a non-zero wind direction (WDIR), indicating non-calm conditions, or vice
versa. The number of occurrences of calm wind conditions are also reported.
AERMET estimates the heights reported in the sounding using the hypsometric equation
z2 = Zi + KRa * Tv/g)\ * ln(pi/p2)
where zl and p, are the height and pressure at the lower level, z2 and p2 are the height and
pressure at the upper level, Rd is the dry gas constant, Tv is the mean virtual temperature through
5-1
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the layer, and g is the gravitational acceleration. The recomputed height is compared to the
reported height. If the difference exceeds 50 meters, then a message is written to the message
file (defined on the MESSAGES keyword). If the surface height is missing, then this check is
skipped.
NWS upper air sounding data contain data for multiple levels, so AERMET will
examine the gradient of several variables within the sounding AERMET checks four different
between- level gradients. Each is expressed as the change o\ er a 100-meter layer because the
change per meter is usually very small. It is important lo remember this distinction if the user
needs to change the default lower or upper bounds The parameter and associated variable name
in AERMET and the default lower and upper bounds are shown in the table below.
Parameter
Variable name
in AERYIIT
1 Jefault lower
bound
Default upper
bound
Ambient temperature gradient
I AI R
-2.0 °C
+5.0 °C
Wind speed shear
UASS
0.0 m/s
5.0 m/s
Wind direction shear
I ADS
0.0 degrees
90.0 degrees
Dew point temperature gradient
I ADD
o
o
o
O
2.0 °C
The \ ertical gradient of the wind \elocily. the wind shear, is a vector quantity. In
AERMI-T. the shear is computed separately for the speed shear (UASS) and direction shear
(UADS) The wind speed shear is computed as the absolute difference in the speeds between
adjacent levels Since it is an absolute difference, it is always non-negative. The wind direction
shear is also an absolute difference.
The vertical gradient of the dew point temperature, unlike the other gradients, is
computed using three consecutive levels. An estimate of the dew point at each intermediate
height is found using linear interpolation between the dew points for the adjacent upper and
lower heights. The gradient of the dew point temperature is defined as the absolute difference
between the estimated and the observed dew point temperature at this intermediate level divided
by the difference between the upper and lower heights.
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The QA on the gradients is summarized with the QA of the observed sounding data.
Because there may be a variable number of levels in a sounding, and the heights of the levels
may differ from sounding to sounding, the results are accumulated into ten height categories.
These are defined as surface, 500-meter layers up to 4000 meters, and above 4000 meters.
Thus, the categories are surface, 0 - 500, 500 - 1000, ..., 3500 - 4000, and 4000+, where each
intermediate category includes the upper but not the lower height. (The "thickness" of the
categories is controlled by the internal variable UPINC This is specified in the module
UPPERAIR and cannot be changed without also recompiling and relinking AERMET.)
Lapse rate and shear violations are tallied in the category containing the upper height,
while those of the dew-point gradient are tallied in the height category of ihe middle
(intermediate) point. In the absence of missing data and wilh .Ylevels in a sounding, there
should be N-1 lapse rate and shear calculations, and A-2 dew -point gradient calculations. All
range violations and instances of missing \ allies are reported in the MESSAGES file and
summarized in the general report.
5.2 Identifying ASOS observations
To implement the ASOS w ind speed adjustment described in Section 3.7.11, AERMET
must determine whether surface wind obser\ ations are from an ASOS site. Wind data in the
standard NW S surface formats read In AERMET are identified as ASOS based on the
published commission date of the ASOS equipment for the WBAN number reported in either
the header of the WVS surface file or the first observation, or the 3- or 4-character station call
letters included in the ohscr\ ations, depending on the format input to AERMET. A table of
commission dates was added to AERMET to support the determination of whether an
observation was measured by ASOS instrumentation. As each observation is extracted from the
NWS surface file during Stage 1 processing, the observation date and time in LST is compared
to the ASOS commission date. Those records for which the observation date falls on or after
the ASOS commission date are identified as ASOS by a "Y" in the ASOS column of the
SURFACE EXTRACT and QAOUT files. If a commission date is not found or the observation
occurred before the commission date, the record is flagged with an "N" in the ASOS column to
5-3
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indicate it is not an ASOS observation. See Appendix C for the format of the SURFACE
EXTRACT and QAOUT files.
For those NWS surface formats that include a data field to indicate that measurements
were made with ASOS instrumentation (HUSWO and in some cases ISHD), a validation is
performed on each record to check the consistency between the ASOS flag in the raw data file
with the ASOS flag set by AERMET based on the commission dale. If the ASOS flag in the
raw data file indicates an ASOS observation, the record in the extracted file will be flagged with
an "A" to indicate an ASOS observation, but a warning will lx- included in the Stage 1 message
file if the station is not found on the ASOS commission list, or if the station is found but the data
period precedes the commission date contained within ^YERMET.
To address cases where an ASOS station is not included in the ASOS commission list in
AERMET but the station is known to he an ASOS site. W:. RMI-T includes an optional
parameter on the DATA keyword under the SURFACE pathway allowing the user to specify
that the data are ASOS Note that this optional 'ASOS" parameter is only allowed for surface
data in the ISHD format and should only be used if the station is known to be ASOS but is not
included in the ASOS commission list within AERMET (see Table A-4 for a description of the
DATA keyword format)
The ASOS commission date and the count of extracted ASOS records are reported in the
Stage I message lile Since I -minute ASOS wind data are presumed to be ASOS, all data from
the hourly a\ eraged I -minute data are assumed to be an ASOS observation.
5.3 Validation of MVS surface format by active data range
Validations are incorporated in AERMET, to check for consistency between the date of
the observation in the NWS surface file and the range of dates for which the NWS format is
active and valid. A file that contains data outside the format's valid date range is assumed to
have been reformatted from some other data format and its use in AERMET may result in
inconsistencies with data processed for the same station and dates input in their native format.
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Use of reformatted data files in AERMET is discouraged, and AERMET results based on
processing reformatted data should be used with caution.
The date consistency check is performed for each hour of data extracted from the NWS
surface file, until an observation is found that is outside the valid date range. Once an
observation is encountered that is outside the valid date range, a variable is set to indicate the
data was likely reformatted, and a warning is issued in the Stage 1 message file when the data
extraction is complete. Table 5-1 lists the active dates lor each of the NWS surface formats read
by AERMET as currently implemented in AERMET. Note that ISIID is currently an active
format and the validation is not performed for the TSIII) format.
Table 5-1. Formal Active Dates
NWS Surface Format
Slarl Dale
End Date
CD-144
12/31/1995
HUSWO
1.1. 1990
12/31/1995
ISHD
SAMSON
1 1 NM
12,31/1990
SCRAM
1 1/1984
12/31/1992
5.3.1 Validation ol'WIS.W between Staae I control lilcandNWS surface data file
Another validation was incorporated into AERMET, beginning with version 11059, to
ensure consistency in the WIJ.W number specified by the user on the LOCATION card in the
Stage 1 SURI'ACI- pathway and the NWS surface data file. The WBAN number from the
control file is compared to the WBAN number stored on the header record of the NWS surface
file (SAMSON) or the WBAN number recorded for the first observation for those formats
without a header record that repeat the WBAN number on each observation record (CD-144,
HUSWO, SCRAM, and TD-3280). When the WBAN number from the control file is found to
be different from that recorded in the NWS surface file, a fatal error is issued, and processing is
aborted. This validation is performed for all NWS surface formats read by AERMET apart
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from the ISHD format since ISHD includes many stations located within the U.S. and
internationally for which a WBAN number has not be assigned.
For those formats in which the WBAN number is repeated on each observation record,
an additional validation is performed to check for internal consistency across all observation
records in the surface file. If a mismatch is encountered, a fatal error is issued, and processing is
aborted. Note: This check for internal consistency is performed for the ISHD format as well as
the other applicable formats; however, since the WBAN number is not consistently included in
ISHD files a fatal error will only be issued and processing aborted if a mismatch occurs between
two non-missing (i.e., not '99999') WBAN numbers Tor the ISIII) format, the validation is
applied to the 5-digit ID stored in positions 11-15 011 each record. The fi rst non-missing (not
'99999') WBAN number encountered is stored and used to compare against each subsequent
record.
5.3.2 ASOS cloud cover from SCRAM and SAMSON set 10 missing
Due to the difficulties thai arise when attempting to reformat cloud cover information
collected with ASOS instrumentation to the SAMSON and SCRAM formats, there are concerns
over the validity of the representation of ASOS clouds in these older pre-ASOS formats. For
this reason. AI-RMI-T was modified (beginning with \ersion 11059)to set opaque and total
cloud co\ er to missing lor observations extracted from SAMSON and SCRAM formats for
which the obser\ ation date falls 011 or after the ASOS commission date. For each hour this
condition is encountered, opaque and total cloud cover are set to missing and warning (up to 24)
or informational messages are issued in the Stage 1 message file. Note that this also applies to
SCRAM-formatted data a\ ailable on the EPA SCRAM website for a few stations that were
commissioned as ASOS during the last four months of 1992, the last year of data archived in the
SCRAM format.
5.4 Site-specific data - averaging sub-hourly values
By default, AERMET assumes that there is one observation period per hour. However,
the site-specific data could contain several observation periods during each hour (AERMET
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allows up to 12). Since AERMET only computes the boundary layer parameters for one-hour
averages, AERMET converts the sub-hourly observations to an hourly average. The user must
tell AERMET the number of observation periods per hour that are in the site-specific data using
the OBS/HOUR keyword. See Section 3.5.13 for a discussion on how to use this keyword. The
site-specific meteorological guidance document (EPA, 1987) suggests at least half of this
number must be present to calculate an average for the hour. AERMET follows this guidance
and computes an average only when half or more of the sub-hourly values are not missing.
For most variables, the hourly value is computed as the arithmetic mean. However, the
wind speed and direction are treated differently to differentiate between cases when values are
missing and cases when values are present but below an instrument's threshold. This value is
defined by the user through the mandatory Tl IRI-SIIOLD keyword. W ind speeds less than the
threshold are given a value of one-half the threshold wind speed and the wind directions are set
to missing. When using the scalar a\ eraging approach, the hourly wind speed is then computed
as an arithmetic mean, while the hourly wind direction is computed according to the method
given in Section 6.1 of the on-site meteorological guidance document (EPA, 2000) to properly
account for the 0°-to-3(-><) crosso\ er When usi ng the \ eel or a\ eraui ng method, the east-west
and north-south components of the wind are calculated based on equations 6.2.13 and 6.2.14
outlined in Section (> 2 2 of the meteorological monitoring guidance for regulatory modeling
applications (N\V 2<)0i)) The hourly average wind speed is then calculated using equation
6.2.15 in (N\V 2<)()0) and the hourly a\ erage wind direction is calculated using equation 6 and
correction methodology listed in Section 4.6 of the AERMINUTE user's guide (EPA, 2015).
To obtain a one-hour a\ erage of the standard deviation variables, the hourly average of
the standard deviation is the square root of sum of variances (square of standard deviation) for
each sub-hourly interval divided by the number of valid observations.
5.5 Station elevations
Beginning with version 06341, AERMET included the option to specify station
elevation above MSL as the last field on the LOCATION keyword in the UPPERAIR,
SURFACE, and ONSITE pathways in the Stage 1 control file, and the METPREP pathway in
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the Stage 3 control file. However, this optional station elevation was only used under version
06341 when processing ISHD data on the SURFACE pathway and all other occurrences of user-
specified station elevations were ignored. Beginning with version 11059, AERMET was
revised to make full use of user-specified station elevations for the SURFACE and ONSITE
pathways to estimate station pressure if station pressure is missing, but to no longer allow
station elevation on the UPPERAIR pathway. The LOCATION keyword has also been
removed from the METPREP pathway beginning with \ cision I 1059, except for one
circumstance. The METPREP LOCATION keyword is now only needed when site-specific
mixing heights are provided during Stage 1 and upper air sounding data are omitted from the
processing. Otherwise, a warning message will be generated if llie I .OC ATION keyword is
included under the METPREP pathway, and the I .OCATION parameters w ill be ignored.
AERMET will issue a warning message if the ele\ alion field is included oil the I PPERAIR
LOCATION keyword, but the user-specified elevation will be ignored, and processing will
continue.
The handling of station ele\ alion w illiin A I - RMI-T. beginning with version 11059, is
summarized below:
A non-fatal warning message will occur if the station elevation is encountered on the
LOCATION keyword on the I 'PPI-RAIR (Stage I) pathway, or if the LOCATION keyword
is included on the MI- IPRI-P (Stage 2) pathway, but the inputs will be ignored and
processing will continue
The station elevation is allowed as an optional argument on the LOCATION keyword for
the SURI-'ACI- and ONSITI- pathways in Stage 1.
If the station ele\ alion is included in the raw SURFACE input file to Stage 1 (ISHD or
SAMSON formats), then the elevation from the data file is used; otherwise, the user-
specified station ele\ alion is used, if available.
If the station elevation is not specified on the SURFACE pathway and is not in the raw
surface data input file for Stage 1, then 0 meters (sea-level) is used for the SURFACE
station elevation.
If the station elevation is not specified on the ONSITE pathway in Stage 1, then 0 meters
(sea-level) is used for the ONSITE station elevation.
Station elevation is used within Stage 2 of AERMET processing in the substitution for
missing station pressure. While station elevation is currently an optional parameter on the
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LOCATION keyword under the SURFACE and ONSITE pathways, users are encouraged to
include station elevation since it may improve the representativeness of the station pressure used
by AERMET if station pressure is missing. The following hierarchy is used for determining
station pressure, based on the availability of ONSITE and/or SURFACE station pressure, sea-
level pressure and station elevation and depending on the source of ambient temperature data:
1. If ONSITE temperature data are used, then:
a. Use ONSITE station pressure, if available.
b. Adjust ONSITE sea-level pressure to ONSITI- station elevation, if provided on
the LOCATION keyword in the ONSITI- pathway¦.
c. Adjust NWS/FAA station pressure to ONSITE station ele\ ation, if station
elevation is available for both the SI Rl ACE and ONSITI- data;
d. Adjust NWS/FAA sea-level pressure to ONSITI- station ele\ ation if ONSITE
station elevation is pro\ ided:
e. Use NWS/FAA station pressure. ifa\ ailahle. without adjustment;
f. Adjust NWS/FAA sea-level pressure to SI RI'ACI- station elevation, if available;
g. Estimate station pressure based 011 standard atmosphere using ONSITE station
elevation, iI"available.
h Estimate station pressure based 011 standard atmosphere using SURFACE station
ele\ation. if a\ailahle.
i Assign ONSITI- sea-le\ el pressure to station pressure if no ONSITE station
ele\ ation is a\ ailahle.
j Assign SI RI ' ACI - sea-le\ el pressure to station pressure if no SURFACE station
ele\ ation is a\ ailahle. or
k. Assign standard sea-level pressure of 1013.25 millibars (mb) to station pressure.
2. If SURFACE temperature data are used, then:
a. Use SURFACE station pressure, if available;
b. Adjust SURFACE sea-level pressure to SURFACE station elevation, if provided
on the LOCATION keyword in the SURFACE pathway or in the SURFACE
data file;
c. Adjust ONSITE station pressure to SURFACE station elevation, if station
elevation is available for both the SURFACE and ONSITE data;
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d. Adjust ONSITE sea-level pressure to SURFACE station elevation, if SURFACE
station elevation is provided;
e. Use ONSITE station pressure, if available, without adjustment;
f. Adjust ONSITE sea-level pressure to ONSITE station elevation, if available;
g. Estimate station pressure based on standard atmosphere using SURFACE station
elevation, if available;
h. Estimate station pressure based on standard atmosphere using ONSITE station
elevation, if available;
i. Assign SURFACE sea-level pressure to station pressure if no SURFACE station
elevation is available;
j. Assign ONSITE sea-level pressure to station pressure if 110 ONSITE station
elevation is available; or
Assign standard sea-level pressure of 1013.25 mh to station pressure.
5.6 Boundary layer parameter est i 111 sites
AERMOD uses se\ eral different Itoundaiy layer parameters to model how pollutants
disperse in the atmosphere Many of these parameters are not observed but are estimated from
other variables that are more easily measured To make these estimates, observed near-surface
wind and temperature (the 'reference' wind and temperature) and site-specific surface
characteristics are required The surface characteristics are discussed in detail in Section 3.7.16,
but because of the importance in estimating boundary layer parameters, they are reviewed
below. 1'ii'st. ho\\e\ cr. is a discussion 011 the criteria for defining the reference wind and
temperature
5.6.1 Reference wind and temperature
If there are site-specific data in the meteorological input to Stage 2, then AERMET
searches these data for near-surface wind and temperature with which to estimate the boundary
layer parameters such as friction velocity and heat flux.
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A valid reference wind is defined as the lowest level with a non-missing wind speed and
direction between 7z0 and 100 meters (inclusive), where z0 is the surface roughness length. If
the only valid non-missing wind speed is a calm wind, then the hour is treated as a calm and the
reference level is the lowest level of non-missing wind.
If there is no valid reference wind, then the lowest level is treated as the reference level
and the reference wind is missing. However, if the option to substitute NWS data is specified in
the control file (see Section 3.7.8 for the keyword MI-TI l()l). and Section 0 for secondary
keyword REFLEVEL), then AERMET will substitute the MVS hourly wind speed observations
for the reference wind speed and use the height specified with the keyword NWSHGT (see
SectionO) as the reference height. If NWS substitution is not specilied. then the reference wind
will be missing.
The selection of the reference temperature is independent of the selection of the
reference wind. A valid reference temperature is defined as the lowest level with a non-missing
temperature between /. and inn meters (inclusi\ e) If there is no \ alid reference temperature in
the site-specific data and the option to substitute NW S data is specified in the control file, then
AERMET will substitute the MVS hourly ambient temperature lor the reference temperature.
In the absence of site-specific data, the MI-TI l()l) keyword with the REFLEVEL
secondary keyword must be specilied lor AERMET to utilize NWS wind and temperature data
for the reference le\ el data NWS data currently are not subject to the criteria above for either
wind or temperature
5.6.2 Surface characteristics
The atmospheric boundary layer is that region between the earth's surface and the
overlying, free flowing (geostrophic) atmosphere. The fluxes of heat and momentum drive the
growth and structure of this boundary layer. The depth of this layer, and the dispersion of
pollutants within it, are influenced on a local scale by surface characteristics, such as the
roughness of the underlying surface, the reflectivity of the surface (or albedo), and the amount
of moisture available at the surface. From these input parameters and observed atmospheric
5-11
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variables, AERMET calculates several boundary layer parameters that are important in the
evolution of the boundary layer, which, in turn, influences the dispersion of pollutants. These
parameters include the surface friction velocity u*, which is a measure of the vertical transport
of horizontal momentum; the sensible heat flux H, which is the vertical transport of heat to/from
the surface; the Monin-Obukhov length Z, a stability parameter relating w* and H\ the daytime
mixed layer height zt and the nocturnal surface layer height //. and n^, the convective velocity
scale that combines zL and H. These parameters all depend on llie characteristics of the
underlying surface.
Although very general default values exist in .YERMET, the user should specify the
albedo (r), which is the fraction of radiation rellecled by the surface; the daytime Bowen ratio,
B0, which is the ratio of the sensible heat flux H to the heat llu\ used in evaporation IE; and the
surface roughness length z0, which is the height above the ground at which horizontal wind
velocity is typically zero. These measures depend 011 land-use type (e.g., urban area,
deciduous/coniferous forest. eulti\ aled land, calm waters) and \ ary with the seasons (See Table
3-1 through Table 3-5) and wind direction.
The user specifies these \ allies 011 SITF. CI l.\R keyword statements for one, four or 12
(AWl \l.. Si: \S()\ \l.. or MONTI II Y) time periods per year, and 1-12 non-overlapping,
contiguous wind direction sectors that co\ er the full 360°. The user is referred to Section 3.7.16
for detailed discussions on these parameters
5.6.2.1 Choice of sccloi-dcnendenl surface characteristics
In defining sectors for surface characteristics, Irwin (1994) and EPA (2000) suggest that
a user specify a sector no smaller than a 30-degree arc. The expected wind direction variability
over the course of an hour, as well as the encroachment of characteristics from the adjacent
sectors with travel time, make it hard to preserve the identity of a very narrow sector's
characteristics. However, using a weighted average4 of characteristics by surface area within a
4 Weighting should be based on wind direction frequency, such as determined from a wind rose
5-12
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30-degree sector makes it possible to have a unique portion of the surface significantly influence
the properties of the sector that it occupies.
The length of the upwind fetch for defining the nature of the turbulent characteristics of
the atmosphere at the source location has been defined as 3 kilometers in EPA's Guideline on
Air Quality Models, which is published as Appendix W to 40 CFR Part 51 (as revised), for the
purpose of defining urban versus rural dispersion characteristics This specification results from
a paper by Irwin (1978), which also cites a study by Flogstrom and Hogstrom (1978). The basic
premise is that when the wind blows over an area with a change in its surface characteristics, a
new "boundary layer" with the turbulent characteristics of the underlying surface develops and
deepens along the wind direction. Hogstrom and I logstrom present tabular results for the
boundary layer growth as a function of roughness length in rural areas. Irwin (1978) noted that
the region of enhanced turbulence with a depth of 4<)i) meters was reported by Shea and Auer
(1978) for St. Louis, and curves based on the Hogstrom anil I logstrom data indicate that a 3-km
fetch would attain this boundary layer height The resulting 3-km letch was also adopted by
METPRO (Paine, 1987). the CTDMPl.l S meteorological pie-processor for its definition of
sector-specific surface characteristics
For a surface with a large roughness. howe\ er. the rate of the boundary layer growth as
defined by Hogstrom anil I logstrom (I l)7S) could he sufficiently rapid to grow to a depth of 400
meters within 1 kilometer ilow nw inil In the case of a lower boundary layer depth, such as 100
meters, the Hogstroms calculate that the distance needed to attain an urban-influenced boundary
height of just 100 meters with a surface roughness ranging from 0.5 to 1.5 meters is only about
250 meters for unstable (coin ective) conditions, 700 meters for neutral conditions, and 1330
meters for slightly stable conditions.
For AERMET applications, an upwind fetch distance of 3 kilometers is recommended
for defining user-specified values such as albedo, Bowen ratio, and surface roughness. In each
sector, it is likely that a mixture of land use is present, and the resulting user input should be a
weighted average of the values selected for each land use type. For urban areas or areas with a
very large roughness length, consideration can be given for a smaller upwind fetch distance for
defining the user-specified surface characteristics. The actual fetch length selected would be a
5-13
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function of the expected plume height, the roughness length, and any urban heat flux that would
tend to minimize the presence of stable conditions in the surface layer. Hogstrom and Hogstrom
(1978) can be used as guidance in these cases.
5-14
-------
6.0 References
Auer, A.H. Jr., 1978: Correlation of land use and cover with meteorological anomalies. J. Appl.
Meteor., 17, 636-643.
EPA, 1987: On-Site Meteorological Program Guidance for Regulatory Modeling Applications.
EPA-450/4-87-013, U.S. Environmental Protection Agency, Research Triangle Park, NC.
EPA, 1997: Analysis of the Affect ofASOS-Derived Meteorological Data on Refined Modeling.
EPA-454/R-97-014. U.S. Environmental Protection Agency, Research Triangle Park,
North Carolina.
EPA, 2000: Meteorological Monitoring Guidance for Regulatory Modeling Applications. EPA-
454/R-99-005. Office of Air Quality Planning & Standards. Research Triangle Park, NC.
(PB 2001-103606)
EPA, 2015: AERMINUTE User's Guide. EPA-454 li-15-006. U.S. Em iron mental Protection
Agency, Research Triangle Park, North Carolina
EPA, 2018: Guidance on the Use of the Mesoscafe \ /odd Interface Program (MMIF) for
AERMOD Applications. EPA-454 B-18-005 1'S I ji\iron mental Protection Agency,
Research Triangle Park, North Carolina
EPA, 2020: User's (lii/de for. IERS( l\i. 1( 1. loot. I .IW-454 li-20-008. U.S. Environmental
Protection Agency. Research Triangle Park. North Carolina.
EPA, 2021a: AERh f()/ > lode/ loriiiiilaiioii am/1 .valuation Document. EPA-454/B-21-003.
US En\ironmental Protection Agency. Research Triangle Park, North Carolina.
EPA, 2< >21 h / ser \ (imdefor the . l.\ IS El'. 1 Regulatory Model (AERMOD). EPA-454/B-21-
i)i)| I S I jivironmeiital Protection Agency, Research Triangle Park, North Carolina.
Hogstrom and 1 logstrom, I lJ78 A Practical Method for Determining Wind Frequency
Distributions for the I .o\\ est 200 m from Routine Data. J. Appl. Meteor., 17, 942-954.
Irwin, J.S., 1978: Proposed Criteria for Selection of Urban Versus Rural Dispersion
Coefficients. Stall" Report. Meteorology and Assessment Division, U.S. Environmental
Protection Agency, Research Triangle Park, NC. (Air Docket Reference No. II-B-8 for
the Fourth Conference on Air Quality Modeling).
Luhar, A.K., and K. N. Rayner, 2009: Methods to Estimate Surface Fluxes of Momentum and
Heat from Routine Weather Observations for Dispersion Applications under Stable
Stratification. Boundary-Layer Meteorology, 132, 437-454.
NOAA, 2003: ASOS Product Improvement Implementation Plan (Addendum III) For Ice Free
Wind. National Oceanic and Atmospheric Administration, National Weather Service,
6-1
-------
Silver Spring, Maryland 20910.
http://www.nws.noaa.gov/ops2/Surface/documents/IFW03i
NOAA, 2008: Cup & Vane Wind Data Processing Within ASOS. National Oceanic and
Atmospheric Administration, National Weather Service, Silver Spring, Maryland 20910.
http://www.nws.noaa.eov/ops2/Siirface/documents/IFWS BetfordWS comparison.pdf
Paine, R. J., 1987: User's Guide to the CTDM Meteorological Preprocessor (METPRO)
Program. EPA-600/8-88-004, U.S. Environmental Protection Agency, Research Triangle
Park, NC. (NTIS No. BP 88-162102).
Ramboll Environ, 2021: The Mesoscale Model Interlace Program (MMIF) Version 4.0 User's
Manual.
Qian, W., and A. Venkatram, 2011: Performance ol'Sieady-Slale Dispersion Models Under Low
Wind-Speed Conditions. Boundary Layer Meteorology, 138. 475-491
6-2
-------
Appendix A. Functional keyword/parameter reference
This appendix provides a functional reference for the keywords and parameters used by
the input control files for AERMET. The keywords are organized by functional pathway and
within each pathway the order of the keywords is alphabetical, excluding the keyword that
identifies the start of a pathway. The pathways used by AERMET are as follows, including the
applicable AERMET processing stages and the in the order in which they appear in the tables
that follow:
JOB - for specifying overall JOB control options (all stages);
SURFACE - for processing NWS hourly Sl'UFACE data (Stages 1 and 2);
UPPERAIR- for processing NWS UPPI.U All* data (Stages 1 and 2).
ONSITE/PROG - for processing ONSITL or PUOGnostic meteorological data
(Stages 1 and 2).
METPREP- lor Mil eorological data PREParation lor use in a dispersion Model
(Stage 2).
Two types of tallies are pro\ ided for each pathway. The first table lists all the keywords
for that pathway, identifies each keyword as to its type (either mandatory or optional, either
repeatable or non-icpealaMc. and if it is reprocessed), and provides a brief description of the
function of the key w ord The second type of table, which may take up more than one page,
describes each parameter in detail
The following conventions are used in these tables. The parameter names are intended
to be descriptive of the input variable being represented. Square brackets around a parameter
indicate that the parameter is optional for that keyword. The default that is used when an
optional parameter is left blank is explained in the discussion for that parameter.
A-l
-------
Beginning with version 21DRF, the maximum record length for the AERMET control
file input file has been increased from 132 to 500 characters. Another important enhancement
introduced with version 21DRF of AERMET, which applies across all pathways, is that the
maximum field length for filenames has been increased from 96 to 300 and the use of double
quotes (") as field delimiters for filenames is allowed to support filenames with embedded
spaces.
JOB-
for specifying overall JOB control options (all stages);
UPPERAIR- for processing NWS UPPEU AIU data (Stages 1 and 2);
SURFACE - for processing NWS hourly SURFACE data (Stages 1 and 2);
ONSITE - for processing ON SITE meteorological data (Stages 1 and 2);
PROG-
for processing PUOGnostic meteorological data (Stages 1 and 2);
MERGE - to MIjRGK the three data types into one file, including 1-minute
ASOS wind data. ifa\ ailahle (Stage 2);
MKTPUKP- lor Mil eorological data PUEParation for use in a dispersion Model
( Stage 2)
Two types of tables are provided for each pathway. The first table lists all the keywords
for that pathway, identi lies each keyword as to its type (either mandatory or optional, either
repeatable or non-repealaMe. and if it is reprocessed), and provides a brief description of the
function of the keyword. The second type of table, which may take up more than one page,
describes each parameter in detail.
The following conventions are used in these tables. The parameter names are intended
to be descriptive of the input variable being represented. Square brackets around a parameter
A-2
-------
indicate that the parameter is optional for that keyword. The default that is used when an
optional parameter is left blank is explained in the discussion for that parameter.
Table A-l. Description of Job Pathway Keywords
Keyword
Type
Description
JOB
Optional,
Non-repeatable
Start of JOB pathway This statement is optional if the statements
associated with this block appear lirstinthe input control file.
CHKSYNTAX
Optional, Non-
repeatable
Flag indicating thai onl\ I lie s\ iua\ of the input statements should be
checked for arm's, i e . no data are processed.
DEBUG
Optional, Non-
repeatable
Flag indicaliim In output debug inlorinniioii for calculations in Stage
1 and 2
MESSAGES
Mandatory, Non-
repeatable
Identifies the warmim error messages file.
NOPRINT
Optional, Non-
repcalahle
I'lau iiidicaliim In suppress priiiiiiii: of information to the screen.
REPORT
()pik>nnl. \i»ii-
repeaiablc
Ideiililies ilie ueneral report tile.
A-3
-------
Table A-2. Description of Keyword Parameters for the JOB Pathway
Keyword
Parameters
CHKSYNTAX
DEBUG
[debugfilename]
where:
debugfilename
Optional name of I lie lile w here all debug information is written; If
no file is named llie default filename is aermet_debug.txt
MESSAGES
messagefilename
where:
messagefilename
The name nl' llie lile where all souive-cude-aenerated messages are
written
NOPRINT
REPORT
summary filename
where:
suniniaiA filename
The name of llie file u here \l !k\ll !T writes a summary of all
preprocessor acli\il> lor llie ainvnl inn
A-4
-------
Table A-3. Description of SURFACE Pathway Keywords
Keyword
Type
Description
SURFACE
Conditional, Non-repeatable
Start of SURFACE pathway.
ASOS1MIN
Optional, Non-repeatable
File name for 1-minute ASOS wind data to be merged in Stage
2
AUDIT
Optional, Repeatable
Identify variables In he audited. These are in addition to any
automaticall> audited \anahle.
DATA
Mandatory, Non-repeatable,
Reprocessed
Input lile name of raw surface data.
EXTRACT
Mandatory, Non-repeatable
File name of extracted surface data
LOCATION
Mandatory, Non-repealable.
Reprocessed
Site ID and location information.
NOMISSING
Optional, Repeatable
Identifies those \ ariahles to O \ and summarize the messages
oul>. detailed messaue identifying the violation and date is
suppressed
QAOUT
Mandators. \ou-icpcalahlc
1'ile name lor hourly surface data for quality assessed
output mei'ue input.
RAN(ii:
()ptioual. kepcalahle.
Reprocessed
Set new upper and lower bounds and missing values for QA of
the variable listed.
XDATES
Mandators. \ou-icpcatable
Inclusive dates identifying the period of time to extract from the
archive data file.
A-5
-------
Table A-4. Description of Keyword Parameters for the SURFACE Pathway
Keyword
Parameter(s)
ASOS1MIN
asoslminfilename
where:
asoslminfilename
Filename for hourly-averaged wind speed and direction derived from
1-minute ASOS wind data (TD-6405), to be merged in Stage 2
AUDIT
sfnamel ... sfnameN
or
ALL
where:
sfnamel ...
... sfnameN
Or
ALL
Name(s) of variables lli;U are lo be tracked and reported during quality
assessment (as de I'm led in Table B-2 of Appendi\ 13) lf"\LL" (case
insensitive) is included, all \ anahles will be audiled
DATA
archivefilename file formal |\S()S|
A-6
-------
where:
archive filename
file format
[ASOS]
The name of the file containing the archive of hourly surface observations
Archive file format; valid parameters are:
CD144
or
SCRAM
or
SAMSON (data ieliie\ ed l iom SAMSON CD-ROM)
or
HUSWO (data reine\ ed liom 11 US WO CD-ROM;
assumes meiric Minis)
or
ISHD (dala in ihe full archival TD-35<>5 format)
Optional parameter lo indicate llial ISI ID data are from an Automated
Sim lace ()hscr\ ing System i \S( )S i siic This parameter is only allowed
Willi the ISI ID file format and nisinicls a^ERMET to apply the wind speed
truncation ad|iisuiicui lo all hours (see Section 2.3.2). Beginning with
\ ersion 1 Iu5'j. \| :k\||: I includes a lable of ASOS commission dates,
w Inch is used lo idcutiK w liedier surface data input to AERMET are from
an \S( )S siie The optional 'ASOS' parameter for ISHD data should only
he used ij the data are known to be from an ASOS site which is not
included in the ASOS station list within AERMET.
NOTH: The blocking factor and data type (ASCII or EBCDIC) parameters
are no longer supported by AERMET, beginning with version 11059. The
defiuill values for these parameters are 1 for blocking factor and ASCII for
dala type. AERMET will issue a warning message if these parameters are
i ucluded on the DATA keyword.
A-7
-------
Keyword
Parameter(s)
EXTRACT
extracteddatafilename
where:
extracteddatafilename
Name of the output file for data extracted from an archive data file
LOCATION
siteid lat(long) long(lat) [tadjust] [elevation]
where:
siteid
lat(long)
long(lat)
[tadjust]
[elevation |
Site identifier for which dala are In he processed.
Station latitude (longiludei in decimal degrees with the suffix N (W) for
sites north (west) of the equator ((neenwich), S (E) for sites south of the
equator ((ncciiu icln
Station loimilude (latitude; 111 decimal dcurces with the suffix W (N) for
sites west ( ikhiIii of Greenwich (of equalon. 1! (S) for sites east of
Greenwich (of cqualon
An integer used to cou\ eri ihe lime reported 111 die dalabase to local
Siaudard time. Formosi surface databases, the value is 0. ForTD-3505
(. 1 SI ID) dala. u Inch is reported in (JMT, the value is the same as the
time /one lor I lie station ie u . a \ alue of 5 forthe Eastern time zone).
Station ele\ alion (in alxn e sea-le\ el): default of 0m if omitted.
NOMISSING
sfnamel sliiamcN
or
\l.l.
w here
sliianicl .
sfnameN
Suppresses missing data messages forthe surface variables specified, as
defined in Appendix B; the number of times the variable is missing is
tallied. If "ALL" (case insensitive) is included, supression will take
place for all variables.
QAOUT
qaoutpul filename
where
qaoutputfilename
Name of the output file from the QA/input to merge data
A-8
-------
Keyword
Parameter(s)
RANGE
sfname lowerbound <[=] upperbound missingindicator
where
sfname
lowerbound
<[=]
upperbound
missingindicator
Variable name, as defined in Table B-2
Minimum value of the valid range of values for sfname
Exclude (<) or include (<=) the lower and upper bounds in the QA
Maximum value of the valid range of values for sfname
Value to use to indicate I lie nhser\ ed variable is missing
XDATES
YB/MB/DB [TO] YE/ME/DE
where
YB/MB/DB
[TO]
YE/ME/DE
Beginning 4-diml > ear. month and da> In extract; Elements can be
separated h\ slashes, dashes, or blanks.
Optional; used In make I Ins record more readable
1 Jidinu 4-dmityear. monili and day to extract; Elements can be separated
In slashes, dashes, or blanks.
A-9
-------
Table A-5. Description of UPPERAIR Keywords
Keyword
Type
Description
UPPERAIR
Conditional,
Non-repeatable
Start of UPPERAIR pathway.
AUDIT
Optional, Repeatable
Identify variables to be audited. These are in addition to any
automatically audited \ ariables.
DATA
Mandatory, Non-repeatable,
Reprocessed
File name of raw upper air data.
EXTRACT
Mandatory, Non-repeatable
File name of eMiacled upper audala
LOCATION
Mandatory, Non-repeatable,
Reprocessed
Sue 11) and location information. Required only for extraction
processiuu
MODIFY
Optional, Non-repcalahle.
Reprocessed
1 lag indicalum curreclinus should be made to the sounding
dala u lieu eMi acted See '5 l or a discussion of these
coiieclKius
NOMISSING
()piinual. Repealahle
kleuiilies ilmse \ anahles lo QA and summarize the messages
nul\. delailed message identifying the violation and date is
suppressed
QAOl I
Maiidalnis. \nu-iepealable
1 ile name of upper air data for quality assessed output/ merge
input
RAN(ii:
Optional, Repealahle,
Reprocessed
Set new upper and lower bounds and missing values for QA of
the variable listed.
XDATES
Maiidalnis. \nu-repeatable
Inclusive dates identifying the period of time to extract from
the archive data file.
A-10
-------
Table A-6. Description of Keyword Parameters for the UPPERAIR Pathway
Keyword
Parameter(s)
uanamel ... uanameN
or
AUDIT
ALL
where:
uanamel ... uanameN
Name(s) of variables ikil are In be tracked and reported during
quality assessment < as defined in Table B-l of Appendix B). If
"ALL" (case insensiinei is included, all variables will be audited.
DATA
archivefilename file format
A-ll
-------
Keyword
Parameter(s)
where:
archivefilename
fileformat
The name of the file containing the archive of upper air data
Archive file format; valid parameters are:
6201FB (TD-6201 fixed-length blocks)
or
6201VB (H)-(.:u| \anable-lengthblocks)
or
FSL for dala ivine\ ed from National Centers for
En\ iroiinieiiial 1 iifornialion (NCEI) web site. Also
a\ailahle on I lie 'Radiosonde Dala of North America' CD-
k( )\1 and online from the Vilional Oceanic and
\liiiospliciii. \diiiiiiistration (NOA\i h System
SRL) Radiosonde 1 )atabase at
¦¦ «/
or
K.KA
l( ik \ dala reli ie\ cd liom National Centers for
1 !n\ ii'oiimciilal liirormalion (NCEI) web site.
NO'l'l-'.: 1 lie blocking factor and data tvne (ASCII or EBCDIC)
paramelei's are no longer supported by AERMET, beginning with
vci'skhi 1 Iu5^ 1 lie default values for these parameters are 1 for
blocking factor and ASCII for data type. AERMET will issue a
u arning message if these parameters are included on the DATA
keyword.
EXTRACT
extmcled dala filename
where:
extracteddatafilename
Name of the output file for data extracted from an archive data file
and the name of the input file for upper air data QA
LOCATION
siteid lat(long) long(lat) [tadjust]
A-12
-------
Keyword
Parameter(s)
where:
siteid
lat(long)
long(lat)
[tadjust]
Site identifier for which data are to be processed.
Station latitude (longitude) in decimal degrees with the suffix N
(W) for sites north (west) of the equator (Greenwich), S (E) for sites
south of the equator (Greenwich).
Station longitude i Inlilndei in decimal degrees with the suffix W
(N) for sites west (nun In nf (neenwich (of equator), E (S) for sites
east of Greenu icli (nl'eqiinioii
An integer used 10 convert the time reported in the database to local
Standard lime. I 'nr siandard npper-air dnln reported in Greenwich
Mean Time i( A IT). llie \ nine is the same as ilie lime zone for the
Milium le u . a \ nine of 5 fur ilie Eastern time zone).
\O IT r.euiiuiiiiu w nil \ eisum 1 1059. the optional station
ele\ alum paianieler is no luimer supported on the UPPERAIR
palliwas
MODIFY
'l K> IIC
Or
\l.l.
Or
l)i:i.\1 \\l) ( \l.\1l)lk SI 13 l l l l)
Where
none or \l.l.
DELMAM)
CALMDIR
SUBTTTD
Delete mandatory levels, set wind direction to 0 for calm wind,
interpolate missing temperature and dewpoint
Delete mandatory levels
set wind direction to 0 for calm wind
interpolate missing temperature and dewpoint
Note; each modification can be listed separately; Listing all 3 is the
same as or ALL
NOMISSING
uanamel . . . uanameN
A-13
-------
Keyword
Parameter(s)
where:
uanamel . . .
. . . uanameN
Or
All
Suppresses missing data messages for the upper air variables
specified, as defined in Appendix B; the number of times the
variable is missing is tallied. If "ALL" (case insensitive) is
included, suppression will take place for all variables.
QAOUT
qaoutputfilename
where:
qa_output_ filename
Name of the ouipui file from l lie HA/input to merge data
RANGE
uaname lowerbound <[=
=] upper hound missingindicator
where:
uaname
Variable name, as defined in Table B-l
lowerbound
Minimum \ nine of llie \ alid range of values for uaname
<[=]
Exclude (< i or include < 11 he lower and upper bounds (the
endpoiuisi in ilie 0 \
upperbouud
Ma\i mum \ alue of the valid range of values for uaname
niissiiiu indicator
\ ;illie lo mdicale llie value is missing
XDATES
Yli WW 1)1! |T<)| yi: \1
: di:
XW WW 1)1!
Beginning 4-digit year, month and day to extract; Elements can be
separated by slashes, dashes, or blanks;
[TO]
YE/ME/DE
Optional; used to make this record more readable
Ending 4-digit year, month and day to extract; Elements can be
separated by slashes, dashes, or blanks;
A-14
-------
Table A-7. Description of ONSITE/PROG Pathway Keywords
Keyword
Type
Description
ONSITE
PROG
Mandatory, Non-repeatable
Start of ONSITE pathway.
Start of PROG pathway
AUDIT
Optional, Repeatable
Identify variables to be audited. These variables are in
addition to an> automatically audited variables.
DATA
Mandatory, Non-repeatable,
Reprocessed
Input file name of site-specific data.
DELTATEMP
Optional, Repeatable,
Reprocessed
Define lieidils i meters) for temperature differences.
FORMAT
Mandatory, Repeatable,
Reprocessed
FORI k \\ formal lor reading one site-specific data record.
LOCATION
Mandatory, Non-repealable.
Reprocessed
Sue II) and location inforniation.
NOMISSING
()ptional. kepealable
Identifies lliose \ anables lo QA and summarize the messages
onl>. detailed message identifying the violation and date is
suppressed
OBS/I K )l k
Optional . Nmi-repealable
Number of observations each hour.
'Mandatory only if the observations are more frequent than
once per hour.
OSHEIGHTS
Opiional . kepealable,
kepiwessed
Define heights of the site-specific measurements.
'Mandatory if the heights are not defined in the data file.
QAOUT
Mandators. Nmi-repeatable
File name of site-specific data for quality assessment output
input
RANGE
Optional, Repeatable,
Reprocessed
Set new upper and lower bounds and missing values for QA of
the variable listed.
READ
Mandatory, Repeatable,
Reprocessed
Defines the name and order of variables as they appear in the
site-specific DATA file.
A-15
-------
Keyword
Type
Description
THRESHOLD
Mandatory, Non-repeatable,
Reprocessed
Sets the minimum wind speed (meters/second) below which
the wind is treated as calm.
XDATES
Optional, Non-repeatable
Inclusive dates for data processing.
A-16
-------
Table A-8. Description of Keyword Parameters for the ONSITE/PROG Pathway
Keyword
Parameter(s)
AUDIT
osnamel . . . osnameN
or
ALL
where:
osnamel . ..
. . . osnameN
Name(s) of variables, as defined in Table B-3 of Appendix B, that are to
be tracked during the i|iialil\ assessment. If "ALL" (case insensitive) is
included, all variables \\ ill he audned
DATA
Filename [land water flag]
where:
Filename
The name of llie lile containing the ON Sill! dala The optional land
water flag denoies if i lie dala are overland (Ol.i oro\ erwater (OW).
The OW flag is onJ> applicable lor the PROG pathway. OL is
applicable I'orMli ONSI11! and I'llOGpathways.
DELTATEMP
index lower height upper liemlil
where:
index
lower lieiulil
upper liemlil
Index lor llie i leniperalure difference measurement
1 .o\\ cr nieasiirenieui height for the ilh temperature difference
I pper nieasiirenieui height for the ifc temperature difference
FORMAT
record inde\ I'oriraii formal
where:
record iude\
Fortran formal
Specifies the record # in the ONSITE data to which the Fortran format
refers; linked to record index on corresponding READ keyword
The Fortran format used to read the ONSITE data record:
May be defined using a Fortran format specifier or as free-formatted
(also called list-directed) data using the optional 'FREE' parameter
(without quotes and not case-sensitive). The Fortran format
specifier must include open and close parentheses and must fit
within the record length of the control file image (up to 132
characters including keyword and record index), and may include
embedded spaces.
A-17
-------
Note that date variables are read as INTEGER format (Fortran 'I'
format) and all other data variables are read as REAL format
(Fortran 'F' or 'E' format). Using an 'F' or 'E' format specifier to
read date variables or 'I' format specifier to read other data variables
will cause an AERMET runtime error. See Section 2.4 for a more
detailed discussion of the READ and FORMAT keywords.
LOCATION
site id lat(long) long(lat) [tadjust] [elevation]
where:
siteid
Site identifier for w Inch dala are In he processed.
lat(long)
Station latitude fur longitude) in decimal degrees with the suffix N for
sites north of I lie equator. S for sites soulli oil lie equator (or W for sites
west of Greeuu icli. 1! for sites east of Greeuu icli i
long(lat)
Station loumiude (or latitude) in decimal degrees with the suffix W for
Mies w est of (ueeiiw icli. 1! fur sues east of Greenwich (or N for sites
no rili of the equator. S lor Mies south of the equator).
[tadjusil
\ii iuieuer used In cou\ eri the lime reported in the database to local
Standard time. lor most onsiie databases, the value is 0.
|ele\ annul
Station ele\ aliou i in ahove sea-level); default of 0m if omitted.
NO_MISSI\( i
iisnamel iiMiaiiic\
or
\l.l.
where:
osiianie 1
osiianiiA
Suppresses missing data messages for the ONSITE variables specified,
as defined in Appendix B; the number of times the variable is missing is
tallied. If "ALL" (case insensitive) is included, suppression will take
place for all variables.
OBS/HOUR
n obs [average method]
where:
nobs
Number of time periods per hour the ONSITE data are reported; for
example if the data are recorded every 15 minutes, then n obs = 4.
Maximum value is 12, corresponding with 5-minute averages.
A-18
-------
If OBS/HOUR is not specified, AERMET will assume 1 observation per
hour. The optional average method will apply to averaging of winds. If
blank or SCALAR, the current averaging method discussed in Section
5.4 will be used. If VECTOR is included, vector averaging will be done
as discussed in Section5.4.
OSHEIGHTS
height 1 ... heightN
where:
heightl . . .
heightN
Heights of the ONSITI! dala measurements; can be used to specify
heights if they are nol included in I lie data file. Must be in ascending
order from lowest to limliesi liemlil 1 f the OSHEIGHTS keyword is
specified and lieiuhis arc also defined in ilie data file, the OSHEIGHTS
input will be used and values in the dala file (1IT01, HT02, etc.) will be
ignored.
See Section 2.5 I'm a mure decided discussion alxuii specifying
measurement heighis
A-19
-------
Keyword
Parameter(s)
QAOUT
qaoutputfilename
where:
qaoutputfilename
File name of the quality assessment output/merge input.
RANGE
osname lowerbound
<[=] upper bound missing indicator
where:
osname
Variable name, as defined in Table B-3.
lowerbound
Minimum value of I lie \ alid raimc of values for osname.
<[=]
Deternimes u liellier lo include ( i or exclude (<) the lower and
upperbounds in the range of accepiahle \ allies Exclude (<) or
include ( i llic lower and upper bounds ulie endpoints) in the QA.
upperbound
\la\iimim value of ilie \ alid range of values for osname.
niissiiiu indicator
\ alne lo use lo indicate ilie \alne is missing.
\()IT. r.euiiiinim w nil \ ersion 11059. AERMET allows the use of
kl! \l. \allies for lower humid, upper bound, and
niissMiu indicator
READ
record mde\ osname 1
osnanie\
u here
record mde\
Links, die list of v anables named on this keyword statement to a
Fortran format defined on a FORMAT keyword statement. While
the corresponding Fortran format specifier must fit within a single
record in the control input file (up to 132 characters total per
record), multiple READ keywords can be used to list variables for a
single read by repeating the same record index.
osname 1 ...
osnameN
Specifies the list and order of variables in the ONSITE data file that
are to be read. See Appendix B for ONSITE variable names.
See Section 2.4 for a more detailed discussion of the READ and
FORMAT keywords.
A-20
-------
Keyword
Parameter(s)
THRESHOLD
thresholdwindspeed
where:
thresholdwindspeed
Minimum valid wind speed for the ONSITE/PROG measurements;
cannot exceed 1.0 ms1
XDATES
YB/MB/DB [TO] YE/ME/DE
where:
YB/MB/DB
Beginning 4-digit year. iikhiiIi and day to extract; Elements can be
separated by slashes, dashes, nr blanks;
[TO]
YE/ME/DE
Optional, used in make lliis record more readable
Ending 4-dmil > ear, month and da> In e\li,icl. Elements can be
separated h\ slashes, daslies. or blanks.
A-21
-------
Table A-9. Description of METPREP Pathway Keywords
Keyword
Type
Description and Usage
METPREP
Mandatory, Non-repeatable
Start of METPREP pathway.
AERSURF
Optional, Repeatable
Specify file name for primary surface characteristics, such as
output file from AERSURFACE; contains FREQ SECT,
SECTOR, and SITE CH AR keyword inputs.
AERSURF2
Optional, Repeatable
Specify file name lor secondary surface characteristics, such as
output file fn 1111 \ 1! R SI k 1' \ CE; inputs in the AERSURF2 file
are interpreted as secondai> sue characteristics, and may
coiilaiii 1 kl :0_SECT2, SECK )k2. and SITE CHAR2
keyword inputs, orFREQSECT, SI C'K)R. and SITE CHAR
keywords 1 Ins allows users to include dala liom an
AERSUR1' \( 1: onipni lile as secondary sue characteristics
w ulkHii having lo edil llie file to change the keywords.
DATA
Obsolete; ignored
FREQSECT
Mandators. Repealahle,
Reprocessed
\nniher of surface characteristics by wind direction sector and
lime period lor i he primary location. Must precede SECTOR
and SITI! ( 11 \k statements, and also must precede secondary
sue ke> words, il'provided.
FREQ SI ( 12
( ondilional . Repealahle.
Reprocessed
\uniher of sni lace characteristics by wind direction sector and
time period for the secondary location.
'Must be specified if both ONSITE and NWS winds are
included, and must precede SECTOR2 and SITE CHAR2
statements.
A-22
-------
Keyword
Type
Description and Usage
LOCATION
Conditional*, Non-
repeatable
The LOCATION keyword under the METPREP pathway in
Stase 2 (old Staee 3) is no lonser used bv AERMET. unless
ONSITE mixing heights are used without any UPPERAIR data.
If UPPER AIR data are
available (with or without
ONSITE mixing heights):
OBSOLETE
For applications with UPPERAIR data, sunrise for CBL height
calculations is based on the primary surface station location in
Stage 1; either llie ()\SITI! pathway, if available, or the
SURFACE pal liu a> \ u aruing message will be generated in
these cases if i lie l.()( \ I K )\' keyword is included under the
METPkl P pathway, and llie MITPREP inputs will be ignored.
Beginning with AERMET
version 13350, if ONSITE
mixing heights are used
without UPPERAIR dala
Mandatory
For applications with onlv ONSITI! iiiimiic heights, without
UPPERAIR data, the LOCATION keyword under the
METPREP should he used to specify the conversion from
(AIT to LSI
METHOD
Conditional .
kepealahle
Specifs processiuu melhodology used for a particular variable,
u helher or not this keyword is mandatory depends on the
processing to be performed and the types of data included in
llie i no rued database
MODEL
()piional. \ou-repealahle
Name of model for which data are processed. Default:
\LRMOD
NWS IKiT
Conditional . \ou-
repealahle
\ \\ S instrument height, in meters, for the specified variable.
* Mandatory if METHOD REFLEVEL SUBNWS is specified
SECTOR
\1aiidalor>. kepealahle,
keprocessed
Defines a wind direction sector in degrees for the primary
location. See also FREQ SECT and SITE CHAR.
SECTOR2
Conditional**, Repeatable,
Reprocessed
Defines a wind direction sector in degrees for the secondary
location. See also FREQ SECT2 and SITE CHAR2.
SITECHAR
Mandatory, Repeatable,
Reprocessed
Define the direction-dependent surface characteristics of
albedo, Bowen ratio, and surface roughness length (meters) for
the primary location. See also FREQ SECT and SECTOR.
A-23
-------
Keyword
Type
Description and Usage
SITECHAR2
Conditional**, Repeatable,
Reprocessed
Define the direction-dependent surface characteristics of
albedo, Bowen ratio, and surface roughness length (meters) for
the secondary location. See also FREQSECT2 and
SECTOR2.
THRESH1MIN
Optional, Non-repeatable
Option to specify a wind speed threshold for winds derived
from 1-minuie \S( )S u md data processed through
AERMINI I I:
U A WINDOW
Optional, Non-repeatable
Specifies the lime u nidnu in use for selecting upper air
souiidiim
XDATES
Optional, Non-repeatable
InclusiN e dates for data processing
** Surface characteristics forthe secondary silo (SECTOR2 and Sill! ( 11 \R2) are required lor applications
with ONSITE data and with the RE] 1.1 \\\. SI I '.NfWS opuoii uiider ihe METHOD keyword to substitute for
missing ONSITE wind data.
A-24
-------
Table A-10. Description of Keyword Parameters for the METPREP Pathway
Keyword
Parameter(s)
AERSURF
AERSURF2
primary surfchar filenam [year listl] (for primary surface data
location)
secondary_surfchar_filenam [year list2] (for optional secondary surface data
location)
where:
primary surfchar filenam
[year listl]
secondary surfchar filenam
[year list2]
The name of I lie file couiaiuiug the surface characteristic inputs
for the primary surface dala location (FREQSECT, SECTOR,
and Si l l! ( II \k keywords)
Opiioual lisi of years associa led Willi \ERSURF
The name of the file containing ihe surface characteristic inputs
for the secondary surface data location < I'kl SECT2,
SLCTOR2. and Sill! (II VR2 keywords)
Opiioual lisl of > ears associated withAERSURF2
DATA
ignored
A-25
-------
FREQSECT
frequency numberofsectors
[year listl] (for primary surface data location)
FREQSECT2
frequency number of sectors [year list2] (for optional secondary surface data location)
where:
frequency
Specifies how often the surface characteristics change; valid
parameters are:
MONTHLY - every calendar month
SEASONAL - u here I lie seasons are defined as:
Spring = March, \pril. \1a>
Summer = June. .1111\. \iiuusi
Autumn September. ()clnher. \n\ ember
Winter December, Januais. I'ehmaiy
AN Nl A1. - constant for the enti re > ea r
numberofsectors
Specifies the number nl' u uid direction seclnrs by which the
suiface characlerisiics \ ar\
Year list 1,
Opiinnal lisi of years assncialed with FREQ_ SECT or
year_list2
i ki:n si:ct:
A-26
-------
Keyword
Parameter(s)
LOCATION
site id lat(long) long(lat) [tadjust] [elevation]
where:
siteid
lat(long)
long(lat)
[tadjust]
[ele\ alinn]
Site identifier for which data are to be processed.
Station latitude (or longitude) in decimal degrees with the suffix N for
sites north of the equator, S for sites south of the equator (or W for
sites west of Greenwich. V. for silos cast of Greenwich).
Station longitude (or latitude) in dccun;il degrees with the suffix W for
sites west of Greenwich. 1! I'm' sites cast of Greenwich (or N for sites
north of the equator. S I'm' sues south oi l lie equator).
An integer used in convert the time reported in I lie dnlabase to local
Standard time. For standard upper-air data reported in Greenwich
Mean Time
-------
Keyword
Parameter(s)
option
Processing ootions:
For UASELECT, valid parameters are:
SUNRIS(E) - select upper air sounding based on local sunrise
For WIND_DIR (not applicable to 1-min ASOS data), valid parameters
are:
NORAND - leave NWS wind directions to the nearest 10°
or RANDOM - randnmi/c WVS \\ 11id directions (default).
For REFLEVEL, valid parameters are
SUBNWS - allows suhsiiiuikm of NWS data for missing ONSITE
wind and/or lemp data (other parameters automatically substituted);
NOTE ilns oniion must be used if no ()\SITE data are orovided.
For STABLI-'.IJI.. \ alid parameters are
BULKRN Jiulk Richardson Number - This opium requires onsite
measurements of leiiipernlme difference.
Al).l_l ' ()piion in adjusi I (surface friction velocity) for low
w md siablc conditions. l or applications without the BULKRN
opium, die \l).l I optinn is based onQianand Venkatram (2011).
l or applications u nil ihc I3ULKRN option, the ADJ U* option is
hascd on l.iiliai aiid Rayner (2009).
1 hi ASOSAD.I. \alid parameters are:
N()_AI).I do not adjust ASOS wind speeds for truncation,
l or ('CA R. \alid parameters are:
SU B_CC - select option to substitute for missing cloud cover
\0_SUB - disable option to substitute for missing cloud cover
NOPERS - disable subs for hrs 23 and 24 based on persistence
Tor TEMP, valid parameters are:
SUB_TT - select option to substitute for missing temperature
NOTSUB - disable option to substitute for missing temperature
(NO_SUB can also be used for TEMP)
NOPERS - disable subs for hrs 23 and 24 based on persistence
NOTE: The CCVR and TEMP substitutions are used bv default, unless
the application involves both NWS and ONSITE surface data, or only
ONSITE data with NRAD or with INSO data and the BULKRN option.
Substitutions can be disabled, and can also be activated for cases with
both NWS and ONSITE data by specifying the appropriate parameters.
A-28
-------
Keyword
Parameter(s)
Substitutions are based on linear interpolation across gaps of 1 to 2
hours, unless the missing data are for hours 23 or 24, where persistence
is assumed. Interpolations are only made based on non-interpolated
values on both sides of the data gap. Also, NOPERS is ignored for
both substitution methods.
MODEL
modelname
where:
modelname
Name of the dispersion model u Inch uses the output files generated by
AERMET. Allowable names are
A1.RMOI)
NWSHGT
variablename instrumentheighl
where:
variablename
Weather variable dial requires an instrumentheighl lo he defined; valid
names are
WEND (luspeulv aiienkHiieler liemlil)
insliiinieiii liemh
t
1 lemlit of the msimnieiil abo\ e umimd. in meters.
OUTI'l 1
parameter filename
w he iv
parameler
filename
Name of the outpnl lile from STAGE 2, with one record per hour
PROFILE
profile filename
where:
profile name
Name of the output file containing multi-level onsite data, or single level
wind and temperature data from NWS site
A-29
-------
Keyword
Parameter(s)
SECTOR
sectorindex beginningdirection endingdirection (for primary data location)
SECTOR2
sectorindex beginning direction ending direction (for optional secondary data location)
where:
sectorindex
Index that links a specific set of site characteristics to a specific wind
sector.
beginningdirecti
on
Specifies the beginning w md diicciioii of the sector, and is considered a
part of this sector.
endingdirection
Specifies the eiidnm u md diieclioii of llie socioi\ and is NOT considered
a part of the scaur
NOTE: The end of one seclor must be the same as ihe hesinnins of the
next sector.
SITECHAR
frequency index scclor nide\ allvdo 1 ioueii roudnicss (forprimary data location)
SITECHAR2
frequciics inde\ seclor nide\ allvdo 1 !o\\ en rouuhiicss (for secondary data location)
where:
frequeiics mde\
sectorindex
albedo
Bowen
roughness
1 ndc\ nl' l he 11 me period lor which the surface characteristics apply;
I'oi'ANM Al.on I k 1 i) SECT keyword, valid values:
1 (for ihe enure \ ean
lor MONTI 11^' on I 'kl !Q_SECT keyword, valid values:
1 12 (corresponding to each month of the year)
lor SI-'.ASONAL on FREQ SECT keyword, valid values:
1 Winter = December, January, February
2 = Spring = March, April, May
3 = Summer = June, July, August
4 = Autumn = September, October, November
Sector corresponding to direction from which the wind is blowing.
Albedo for the frequency index and sector index specified.
Bowen ratio for the frequency index and sector index specified.
Surface roughness for the frequency index and sector index specified.
A-30
-------
Keyword
Parameter(s)
THRESH1MIN
thresholdspeed
where:
thresholdspeed
Threshold wind speed in m/s for wind speeds derived from 1-minute
ASOS wind data processed through the AERMINUTE program. If
the user specifies a threshold speed greater than 0.5 m/s, a warning is
issued by AERMET. If a threshold wind speed greater than 1.0 m/s is
specified, AERMET considers llns a fatal error, will issue an error
message and will not process dala llirough Stage 2.
UAWINDOW
windowbegin windowend
where:
windowbegin
windowend
Beginning of llic sounding u indow, entered as i lie number of hours
relative lo ilie preferred sounding time < 12/.. no/, or-12Z forthe
default selection: or local sunrise forthe UASI !l.l XT SUNRIS
opiion)
1 indium of ilie siiuudiim u uidou eniered as the number of hours relative
lo llic preferred snuudiim nine
NO 11! \ ncualiN e uuniher iiidicales i lie number of hours before the
reference siuiudum (or sunrise), and a positive number indicates the
number of hours al'ler llic sounding (or sunrise)
XDATES
YI5 \1li 1)13 |K)| \\. WW l)i:
w here
YI5 WW 1)15
[TO]
\\ ww di:
IJcmuiiiim 4-d luil \ear. nioiiih and day to extract; Elements can be
separated by slashes, dashes, or blanks;
()puoiial; used to make this record more readable
Ending 4-digit year, month and day to extract; Elements can be separated
by slashes, dashes, or blanks;
A-31
-------
Appendix B. Variable names and default QA values
This appendix lists the variable names for each type of data and provides a short
description of and the units for each variable and gives the default bounds and missing value
codes. This information is presented in the tables that follow with each table divided into the
following fields:
Variable Name
This is the four-character name that can be used on R.Wil-. \l l)IT, and READ statements.
An asterisk (*) indicates that the variable is automatically included in the QA for the path and
need not be specified on an AUDIT record in the control file.
Description and Units
A brief description of each variable and the units follow the name. For UPPERAIR and
SURFACE, real variables are stored as integers, in which case the units include a multiplier,
such as *10 or *100. to maintain additional significant digits for example, if the units are
°C*10, then 1.5 °C is stored and referenced as I 5
Tvne of Check
The type of check determines u hether to include (<=) or exclude (<) the lower and upper
bounds in the range of acceptable values and can be changed on a RANGE statement for
specific variables
Missing Value Code
The missing value code is the value that AERMET interprets to mean that a value is not present.
It is also the value written/stored by AERMET when the variable is not present or cannot be
calculated.
B-l
-------
Bounds
The last two fields are the lower and upper bounds that determine the interval of acceptable
values. The value of the variable is accepted if it lies within this interval, where the endpoints
are either included or excluded according to the Type of Check. Note that the multiplier, if
present, must also be applied to these values.
B-2
-------
Ta
jle B-l. Variable and QA Defaults for SURFACE Variables
Variable
Name
Description
Units
Type
Missing
Indicator
Lower
Bound
Upper
Bound
PRCP
Precipitation amount
millimeters* 100
<=
-9
0
25400
SLVPt
Sea level pressure
millibars* 10
<
99999
9000
10999
PRES
Station pressure
millibars* 10
<
99999
9000
10999
CLHT
Ceiling height
kilometers* 10
<=
999
0
300
TSKC
Total//opaque sky cover
tenths//tenths
9999
0
1010
ALCla
Sky cond//height, level 1
code//hundred1hs It
09999
0
07300
ALC2a
Sky cond//height, level 2
code liiiiidredllis ft
09999
0
07300
ALC3a
Sky cond//height, level 3
code hundredths ft
<=
09999
0
07300
ALC4b
Sky cond//height, level 4
code liiiiidredlhs fi
<=
iwm
0
07850
ALC5b
Sky cond//height, level 5
code'/hundredills fi
<=
09999
0
07850
ALC6b
Sky cond//height, level 6
code liiiiidredlhs l'i
<
09999
0
07850
PWVC
Present weather (vicinity)
9999
0
9800
PWTH
Precipitalkm i\ pe
9999
0
9800
ASKY°
ASOS Sk\ anitliiKni
lenllis
<=
99
0
10
ACHTd
ASOS Ceilinu
kilometers* In
<=
999
0
888
HZVS
1 liiriAinial \ isihilns
kilometers* |u
<=
99999
0
1640
TMPI)
Diy bulb temperature
°C*10
<
999
-300
360
TMPW
Wei hnlb temperature
C*10
<
999
-650
350
DPTP
Dcw-pmui temperature
°C*10
<
999
-650
350
RHUM
Relative liiiinidii\
whole percent
<=
999
0
100
WDIR*
Wind direction
tens of degrees
<=
999
0
36
WSPD*
Wind speed
meters/second* 10
<=
999
0
500
B-3
-------
Automatically included in audit report,
t A value < 800 in CD144 files is converted to SLVP/10.0 + 1000.0
// The two variables have been combined to form one variable; the missing value flags, as well as the upper and lower
bounds have also been concatenated.
a ASOS sky condition (code table) and height (hundredths of feet) for levels 1 -3
b ASOS sky condition (code table) and height (hundredths of feet) for levels 4-6
(for augmented sites)
c ASOS sky condition (tenths), derived from layer data.
d ASOS ceiling (kilometers *10), derived from layer data.
B-4
-------
Ta
)le B-2. Variable and QA Defaults for UPPERA
R Variables
Variable
Name
Description
Units
Type*
Missing
Indicator
Lower
Bound
Upper
Bound
UAPR
Atmospheric pressure
millibars* 10
<
99999
5000
10999
UAHT
Height above ground
meters
<=
99999
0
5000
UATT
Dry bulb temperature
°C*10
<
9990
350
+350
UATD
Dew point temperature
°C*10
<
9990
350
+350
UAWD
Wind direction
degrees from noiih
999
0
360
UAWS
Wind speed
meters/second 1 < >
9990
0
500
UASS
Wind speed shear
(m/sVnill) mckTs)
9999
0
5
UADS
Wind direction shear
degrees < 1 u< > meters)
<=
9999
0
90
UALR
Temperature lapse rate
°C/(lUU melers)
<=
WW
2
5
UADD
Dew point deviation
( < 100 meters)
=
9999
0
2
* Type determines whether to include ( )me\dude( 11 lie lower and upper bounds in the range of acceptable
values, and can be changed on a RANGE sialemeiil
B-5
-------
Table B-3. Variable and QA Defaults for ONSITE or PROG Single Level and
Date/Time Variables
Variable
Name
Description
Units
Type
A
Missing
Indicator
Lower
Bound
Upper
Bound
1II 1 X
Surface sensible heal flu\
walls square nieler
-999
-100
800
I.l'I.X
Surface latent heat flux
walls square meter
-999
-100
H00
USTR
Surface friction velocity
meters/second
-9
0
2
MHGT
Mixing height
meters
9999
0
4000
/.Oil 1
Surface iiiuuhuess leuulh
meters
999
0
J
SAMT
Snow amount
centimeters
999
0
250
PAMT
Precipitation amount
ceniiuieleis
<=
999
0
25
INSO
Insolation
watls square meler
<=
9999
0
1250
NRAD
Net radiation
watts/square meler
<
999
-100
800
DT01
Temperature diff.(U - L)1
°C
<
9
-2
5
DT02
Temperature diff.(U - L)1
°('
9
-2
5
DT03
Temperature diff.(l' - J.) 1
°('
<
9
-2
5
\ KKi
l\ii\ccli\c \ek»cil\ scale
m/s
-9
()
J
\i.i:d
\lhedn
Diuieiisuiiiless
999
()
1
r.o\v\
lioweii ralio
diuieusuuiless
999
-10
10
i'k( i'
I'lvcipilalmn
millimeters* 100
<=
-9
0
25400
SLVP
Sea le\ el pressure
millibars* 10
<
99999
9000
10999
PRES
Station pressure
millibars* 10
<
99999
9000
10999
CLHT
Ceiling height
kilometers* 10
< =
999
0
300
TSKC
Sky cover (total or opaque)
tenths
<=
99
0
10
OSDY
Day
<=
-9
1
31
OSMO
Month
<=
-9
1
12
OSYR
Year
<=
-9
0
99
OSHR
Hour
<=
-9
0
24
OSMN
Minutes
<=
-9
0
60
B-6
-------
1 (U - L) indicates (upper level) - (lower level).
* Type determines whether to include (<=) or exclude (<) the lower and upper bounds in the range of acceptable values, and can
be changed on a RANGF. statement.
Note: Shaded parameters are only used lor overwaler applications.
Pammcters in Italics arc not used hv AI'JIMPT.
B-7
-------
Ta
jle B-4. Variable and QA Defaults for ONSITE or PROG Multi-level Variables
Variable
Name
Description
Units
Type
Missing
Indicator
Lower
Bound
Upper
Bound
HTnn
Height
meters
<
9999
0
4000
SAnn
Std. dev. horizontal wind
degrees
<
99
0
35
SEnn
Std. dev. vertical wind
degrees
<
99
0
25
SVnn
Std. dev. v-comp. of wind
meters/second
99
0
3
SWnn
Std. dev. w-comp. of wind
meters/second
99
0
3
SUnn
Std. dev. u-comp. of wind
meters/second
99
0
3
TTnn*
Temperature
°C
99
-30
40
WDnn*
Wind direction
degrees from north
<=
999
0
360
WSnn*
Wind speed
meters/second
<=
0
50
Wnn
Vertical wind component
meters/second
<
999
0
5
DPnn
Dew-point temperature
°C
99
-65
35
RHnn
Relative liiimidilv
u hole peivenl
999
0
100
Vlnn
User's vector 1
user's units
999
0
100
V2nn
User's vector 2
user's units
999
0
100
V3nn
( ser's vector 3
user's units
999
0
100
'nn ' in variables HI' to V3 refers to the level at which the observation was taken; e.g., TT01 is the temperature at the
first level and WS02 is wind speed at the second level.
"Automatically included in audit report.
Note: Parameters in italics are not currently used in AKRMKT.
B-8
-------
Appendix C. Data File Formats
This appendix describes the format of the data files created by AERMET. This includes
the EXTRACT and QA files of NWS upper air and surface data, the QAOUT file for site-
specific or prognostic data, and the OUTPUT and PROFILE files that will be input to
AERMOD.
C. 1. EXTRACT/QAOUT files
C-l
-------
Table C-l and Table C-2 list the format of the EXTRACT and QAOUT files for the
SURFACE and UPPER pathways. Note that different variables are output for each of the two
file types. The EXTRACT file contains the variables needed in Stage 2. The QAOUT file
contains the same variables plus any additional variables that are QA'd but not needed for Stage
2. Table C-3 lists the format for the QAOUT file for the ONSITE or PROG pathway. Note for
ONSITE or PROG data, if heights are read in, either with the HT variable or OSHEIGHTS, they
will be the first variable listed in the QAOUT file, regardless of the order they were read in the
raw data file. Remaining variables are then listed based 011 their order in the subroutine
ONSITE INIT in the ONSITE module
C-2
-------
Table C-l. SURFACE EXTRACT and QAOUT file header format and data format.
Header section
Row Number
Description
1
AERMET version number
2
Location information
3
File type (EXTRACT or QAOUT)
4
Date of data period
>4
Optional Range modifications1
>4
Data header
Data section
Column2
Description
DATE
Date (YYYMMDD) inLST
HR
Hour of observation in LST
ASOS
ASOS status for hour (Y=AS( )S observation. N=non-AS( )S ohser\ ation
PRCP
Precipitation (mm)
SLVP
Sea level pressure (mb)
PRES
Station pressure < mh)
TSKC
Total/opaque cloud co\ or
PWTH
Precipitation t> pe
ASKY
ASOS skv condition
TMPD
l)r\ hulh temperature ( ( i
DPTP
Dew point temperature < ( )
RHUM
kclali\c humidils (percent)
WD1R
Wind direct ion
WSPD
Wind speed (m/s)
ALC1
Skv condition/height, level 1
ALC2
Sky condition/height, level 2
ALC3
Skv condition/height, level 3
ALC4
Skv condition/height, level 4
ALC5
Skv condition/height, level 5
ALC6
Skv condition/height, level 6
PWVC
Present weather
ACHT
ASOS ceiling
HZVS
Horizontal visibility
TMPW
Wet bulb temperature
1 The RANGE values are output for variables that are changed from the default missing value or bounds.
2 Shaded variables are in the QAOUT file only if audited.
C-3
-------
Table C-2. UPPERAIR EXTRACT and QAOUT file header format and data format.
Header section
Row Number
Description
1
AERMET version number
2
Location information
3
File type (EXTRACT or QAOUT)
4
Date of data period
>4
Optional Range modifications1
>4
Data header
Data section
Column2
Description
DATE
Date (YYYMMDD) inLST
SND
Sounding number for the d; i\
HR
Hour of sounding in LST
LEV
Level number
UAPR
Pressure of le^ el < mhi
UAHT
Height of level inn
UATT
Dry bulb temperature < ( )
UATD
Dew point temperature ( ( )
UAWD
Wind direction of level
UAWS
Wind speed of level (ni/s)
UASS
Wind speed shear (m/s)/( 100 m)
UADS
Wind direction shear dcgrccs/( 100 m)
UALR
Temperature lapse rate °C/(100 m)
UADD
Dew point deviation °C/( 100 m)
1 The RANGE values are output for variables that are changed from the default missing value or bounds.
2 Shaded variables are in the QAOUT file only if audited.
C-4
-------
Table C-3. ONSITE/PROG EXTRACT and QAOUT file header format and data format.
Header section
Row Number
Description
1
AERMET version number
2
Location information
3
File type (QAOUT)
>3
Threshold speed (m/s)1
>3
Temperatures used for DELTA TEMI'
>3
Overland (OVERLAND) oroverwaicr <( )\ 1 !R\V \ I I !IO flag
>3
Date of data period
>3
Optional Range modifications"
>3
First and last level for multi-le\ el \ ai iables1
>3
Data header
Dalii section
Column
Description
DATE
Date (YYYMMDD) in T.ST
HR
Hour of soundnm in I.ST
LEV
Level number
HTNN
Height of level
OSVAR1
\ anahlc 1
OSVARN
\ anahle \
1 If applicable
2 The RANGE values are output for variables that are changed from the default missing value or bounds.
3 After the height variable, variables are written in the order they are listed in subroutine onsite init in
mod_onsite.f90 and shown in Table B-3 and Table B-4 in Appendix B
C-5
-------
C. 2. OUTPUT and PROFILE outputs
Table C-4 and Table C-5 list the formats for the OUPUT (surface data and boundary layer
parameters) and PROFILE file output from AERMET for input to AERMOD.
C-6
-------
Table C-4. OUTPUT file format.
Header section
Variable
Description
1
Latitude of primary surface station
2
longitude of primary surface station
3
Upper air station identifier
4
Surface station identifier
5
Onsite or prognostic station identifier
6
AERMET version
7
Various information such as the use of ad|iisicd ir. 1 Sulk Richardson number use, and
MMIF version
Data section
Column
Description
year
2-digit year
month
2-digit month
day
2-digit day of month
j_day
Julian day of year
hour
Hour of day in LST
H
Sensible heat flux (W/nr)
u*
Surface friction velncilv iiiim
w*
Connective velocih scale (in si
VPTG
\ cilical potential leniperciliire madicni abn\c /.ic
-------
When site-specific data are included in the data base, the definition of the reference
height wind speed and direction are subject to the following restrictions:
the wind speed, Ws, must be greater than or equal to the site-specific data threshold wind
speed;
the measurement height must be at or above 7*zn. where zn is the surface roughness
length;
the height must be less than or equal to 100 meters:
If AERMET is run only with NWS data. i.e . no silo-specific data are in the data base,
then the restrictions above do not apply, and llio reference winds are laken lo be the NWS winds
independent of the height at which the winds were measured
Ambient air temperature is subject to a similar, but less restrictive, selection process:
the measurement height must be abo\ e z... and
the height must be less than or equal to loo meters
C-8
-------
Table C-5.
>ROFILE file format.
Column
Description
year
2-digit year
month
2-digit month
day
2-digit day of month
hour
Hour of day in LST
height
Height of level (m)
top
1 if this is the last level for the hour, 0 otherwise
WDnn
Wind direction at current level (degrees)
WSnn
Wind speed at current level (m/s)
TTnn
Temperature at current level (°C)
SAnn
Standard deviation of wind direction, a < derives i
SWnn
Standard deviation of vertical w ind speed. c,w
C-9
-------
Appendix D. Messages
During processing, AERMET writes messages to the file defined by the MESSAGES
keyword on the JOB pathway. Each message has the form:
Pathway code subroutine message
Where pathway is the pathway defined in the control file (JOB. TWERAIR, SURFACE,
ONSITE, PROG, or METPREP). The code is a three-character code with the first character
being an "E" for error, "I" for informational, "Q" for quality assurance (audit) and "W" for
warning. The latter two characters are a numeric siring lo link the code to a specific message
type. The subroutine identifies the subroutine in u hicli the event thai trigged message occurred
and finally the message is the actual message identifying the issue. Error messages lead
AERMET to abort processing, warning messages identify potential issues that are not fatal but
may require attention and informational messages relay information to the user, such as the
commission date for an ASOS station Oiiulity assurance messages alert the user of missing or
values out of bounds so they may lit the warning and informational categories.
D-l
-------
D. 1. Error messages
Error codes E01-E08 generally refer to control file processing, E30-39 refer to
UPPERAIR processing, E40-E47 refer to SURFACE processing, E50-E65 refers to ONSITE or
PROG pathway, and E70-E80 refers to the METPREP pathway.
E01 Invalid path or keyword; syntax error in AERMI-T control file
E02 Invalid filename or duplicate filename
E03 Incorrect number of fields or invalid paramclcis lor a keyword; duplicate entry of
keyword
E04 Invalid or obsolete file format
E05 Invalid option for keyword or invalid variable
E06 Missing path identifier
E07 Invalid path pairings, i.e., SI RI'ACI-with PROG
E08 Missing keyword
E30 Sounding ilk- not in specified formal (IGRA. (OnI. I SI.)
E31 Error reading sounding data line
E32 Invalid date fields in upper air data file
E33 ln\alid wind speed units lor I'SI. sounding data
E34 Multiple surface data lines for a gi\ en sounding for FSL or IGRA sounding data
E35 Multiple versions of I'SI. formats detected for FSL sounding data file; missing value
indicators or pressure conversion indicate multiple versions
E36 Number of le\ els read for FSL or IGRA sounding data does not match expected
number of levels for a sounding
E37 No soundings extracted but no errors
E38 Sounding extraction not completed
E39 No soundings extracted with errors
E40 Error reading data line for surface observations
E41 Error reading dates for hourly averaged 1-minute ASOS data
E42 Invalid date fields in surface data file
D-2
-------
E43 Invalid elevation field in surface data file
E44 Invalid station coordinates in surface data file
E45 Invalid SAMSON header record in surface SAMSON data file
E46 More than one set of header records in surface SAMSON data file
E47 Invalid station identifier in surface data file
E50 Number of instances of READ keyword do not match number of instances of
FORMAT keywords for ONSITE or PROG pathways
E51 OBS/HR not present when OSMN variable read from data. OBS/HR > 1 and OSMN
not read from data
E12 Date/time variables not read with first Rl-Al) statement or date/time variables not first
set of variables for a READ statement
E13 First or last character of FORMAT statement is not a parenthesis, Number of left and
right parentheses in FORMAT statement do not match
E14 No DELTA TEMP heights listed for DT01
E65 Number of RI-AD statements exceeds maximum allowed or error reading ONSITE or
PROG OAOl I file
E56 Number ofobser\ ations hour exceeds \ alue ofOBS IIR for sub-hourly site-specific
data
E57 Number of heights specified l\v OSI ll-IGI ITS not equal to number of HT levels if
both OSI II- Kil ITS specified and height is read in from site-specific or prognostic data
file
E58 Input data heights not increasing with each READ statement for a given hour when
reading site-specific or prognostic data file and height is read from data file.
E59 Invalid date time \ ariable found in QAOUT data; variable is not one of the first
variables on the line of data.
E60 ONSITE or PROG wind speed and direction not processed together. If one is read in,
the other should be as well.
E70 No valid data available based on input dates and available data for UPPERAIR,
SURFACE, ONSITE, or PROG data.
E71 LOCATION keyword missing; needed when MIXHTS included in ONSITE or PROG
data and no UPPERAIR data.
D-3
-------
E72 NWS_HGT missing if processing SURFACE data and SUBNWS invoked
E73 Surface characteristics keyword(s) missing
E74 Invalid year for multi-year specified surface characteristics or year has not been
assigned or assigned more than once. Applies to both primary and secondary sites.
E75 Invalid surface characteristics parameter (invalid frequency, sector number). Applies
to both primary and secondary sites.
E76 Duplicate listing of SITECHAR, SITECHAR2. SI X'TOR., or SECTOR2. This is
not trigged when multiple years are associated with surface characteristics
E77 Invalid combination of item with action, i.e., ST.Mil.Nil. paired with RANDOM
E78 UAWINDOW beginning hour after ending hour
E79 Invalid variable for NWS HGT
E80 Invalid value for NWS HGT height (not a number or height < <> m)
D-4
-------
D. 2. Warning messages
Warning codes W01-W03 generally refer to control file processing, W30-35 refer to
UPPERAIR processing, W40-W55 refer to SURFACE processing, W60-W69 refers to ONSITE
or PROG pathway, and W70-W81 refers to the METPREP pathway.
W01 Too many fields associated with keyword (usually obsolete fields such as blocking
factor) or obsolete keyword or path ignored; extra fields will be ignored.
W02 Duplicate listing of variable for items such as AI 1)11. \( >_MISSING, RANGE, etc.
W03 Extraction dates will be determined In MI-'TPRI-P \l).\TI!S if UPPERAIR,
SURFACE, ONSITE, or PROG XD ATI-S missing in combined stage 1 and 2
AERMET runs.
W30 Upper air station WBAN in data file does not mulch user entered station II)
W31 First level of sounding not surface le\ el. skip sounding
W32 Surface level height missing, skip sounding
W33 Reached li mil of warning code specified in message for upper air data
W34 No upper air data extracted as specified In dates with XDATES keyword. Check
XDATES
W35 Sounding data not in temporal order
W40 Station Wli.W in data file does not match user entered WBAN or previous record's
WIJ.W Also issued u hen AI!R\I l\l "IT! WBAN does not match user entered
WIJ.W
W41 User may ha\ e entered WMO number instead of WBAN; consider entering WBAN
in control file
W42 Limit reached on number of warning messages
W43 Station elevation missing in SURFACE data file or does not match user entered
elevation.
W44 Station coordinates not provided in SURFACE data file
W45 Station is flagged as ASOS station but no commission date or before ASOS
commission date; also issued when the ASOS flag switches after commission date
D-5
-------
W46 No surface data extracted as specified by dates with XDATES keyword. Check
XDATES
W47 Invalid entry for CD-144 variables or HUSWO cloud cover
W48 AERMINUTE output does not overlap with surface data XDATES.
W49 Surface data not in temporal order
W50 Observation is outside accepted dates for processed SURFACE data format.
W51 Variable exceeds a specified threshold. Currently this is applicable to threshold wind
speed specified by the THRESHOLD keyword or A SOS wind speed exceeds a
specified threshold for SURFACE data.
W52 ASOS flag set for non-ISHD data with DATA keyword lor SURFACE data; reset to
non-ASOS
W53 ASOS flag set for SURFACE station in ASOS list based on ty'li AN number
W54 ASOS flag set for SURFACI- station not in ASOS list hased on YVIJAN number
W55 SURFACE station found in ASOS list for non-ISI II) data file
W61 First level for wind speed and direction not equal or unequal number of levels for
wind speed and wind direction for ONSITI- or PROG data
W62 Site-specillc or prognostic data not in temporal order
W63 Data line in raw site-specille or prognostic data does not match FORMAT statement
associated with RI-AI) statement for line
W64 Variable read from ONSITI- or PROG data 11 le but is not used by AERMET and will
be ignored.
W65 Variable exceeds a specified threshold. Currently this is applicable to threshold wind
speed specified by the Tl [RESHOLD keyword or ASOS wind speed exceeds a
specified threshold for SURFACE data.
W66 OBS/HR=l with OSMN being read in; OSMN will be ignored in data.
W67 OSHEIGHTS specified and HT read in ONSITE or PROG data; HT will be ignored
and OSHEIGHTS will be used.
W68 ONSITE or PROG variable being audited but not read in from data; Ignore audit
W69 DELTA TEMP listed but not DT01, warn user that temperatures may be used.
W70 LOCATION keyword not needed for METPREP or extra field with LOCATION
keyword
D-6
-------
W71 NWSHGT not equal to ASOS anemometer height in internal ASOS list
W72 NWS HGT height > 30 m
W73 Not enough variables for stable boundary layer calculations; cloud cover and net
radiation not read in and or no insolation and BULKRN calculations not performed.
W74 Secondary site surface characteristics listed but not needed.
W75 Variable exceeds bounds (this is not the same as upper and lower bound checks when
auditing) or may be suspect
W76 Upper air sounding not extended.
W77 Convective mixing height exceeds original sounding lop
W78 W*< 0.001, reset to 0.001
W79 MMIF version found for data while usi ng ()NSITE pathw ay
W80 Multiple MMIF versions detected
W81 Obsolete parameter detected and will be ignored
D-7
-------
D. 3. Informational messages
Information code 101 refers to control file processing, 120-27 refer to UPPERAIR
processing, 140-159 refer to SURFACE processing, I60-W67 refers to ONSITE or PROG
pathway, and 170-183 refers to the METPREP pathway.
101
Alert user of processing stage or stages
120
Upper air extraction process begin or end date'time
121
Duplicate sounding found for hour
122
End of data window (set by XDATES) reached, no further data extraction
123
Mandatory level deleted or sounding has no levels after deleting mandatory levels
124
Wind direction set to 0 for calm wind in sounding
125
Reset missing temperature
126
Reset missing dewpoint
127
Could not compute layer index lor auditing
140
Surface data extraction process begin or end date/time
141
ISHD data obser\ ation not within accepted mini Iter of minutes of the hour
142
ISHD record type not processed
143
Potential duplicate obser\ ation found lor the hour
144
Special report used for hour from ISIII) data
145
()hscr\ ation for the hour replaced with new observation from ISHD data
146
Number of extracted surface observations
147
Number of retained surface observations
148
Number of special surface ISHD observations used
149
Number of regular surface ISHD observations used
150
Number of duplicate surface observations not used
151
Number of special surface ISHD observations not used
152
Number of regular surface ISHD observations not used
153
Number of overwritten surface observations
154
Number of non-supported ISHD observations read
155
Number of observations outside acceptable number of minutes within the hour
156
Number of calm observations
D-8
-------
157
158
159
160
161
162
163
164
165
166
167
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
Number of variable wind observations
SAMSON observation may be modeled
ASOS commission date
Site-specific or prognostic data extraction process begin or end date/time.
List of DELTA TEMP heights
Potential duplicate site-specific or prognostic sub-hourly or hourly observation
Number of extracted site-specific or prognostic obser\ alions
Number of duplicate site-specific or prognostic ohser\ alions
Number of sub-hourly site-specific or prognostic ohser\ alions not used
Number of bad height levels
Location is overland and certain variables will be read but not used
PBL processing begin or end date/time
Missing insolation and cloud cover
Temperature and/or pressure missing, or winds calm or missing, skip calculations for
the hour.
Wind measurement height 2d times /,.
Wind speed square root of 2 times minimum o>. reset wind to square root of 2
times minimum
Cloud aTser missing, skip calculations
Net radiation n lor stable hour
No coin ecti\ e parameters calculated for the day depending on sounding isues
Coin ecti\ e mixing height set to maximum allowed convective height or mechanical
mixing height set to maximum allowed mechanical mixing height
Location is o\ erlaiul and certain variables will not be used from stage 1 output
Heat flux <= n for coin ective hour, reset to 0.1
Bulk Richardson number approach not used
MMIF version found
Alert user how stability determined for each hour, Monin-Obukhov length or solar
angle.
If site-specific u* for the hour and adjust u* requested, alert user that u* will not be
adjusted.
D-9
-------
D. 4. Quality assurance messages
Quality assurance messages Q20-Q28 refer to UPPERAIR processing, Q40-Q47 refer to
SURFACE processing and Q60-Q70 refer to ONSITE/PROG processing.
Q20 Cannot recompute heights of sounding
Q21 Difference between observed height and recomputed height > 50 m
Q22 Height is missing for a level, cannot compute VASS. I ADS, UALR, or UADD
Q23 Variable missing for level
Q24 Variable violates lower bound for level
Q25 Variable violates upper bound for le\ el
Q26 Wind speed is zero for non-zero wind di reelion or calm for le\ el
Q27 Temperature < dewpoint for level
Q28 Top of sounding < 5 km
Q40 Variable missing
Q41 Variable violates lower bound
Q42 Variable violates upper bound
Q43 Calm wind
Q44 Wind speed <> and uind direction n
Q45 W ind speed <> and uind direction n
Q46 \on-xcro precipitation without weather
Q47 Went her without non-zero precipitation
Q60 Report lirst level for \ ariaMe
Q61 Missing \ allie for variable (specific level for multi-level variable)
Q62 Variable violates low er bound (specific level for multi-level variable)
Q63 Variable violates upper bound (specific level for multi-level variable)
Q64 Wind speed < threshold for level
Q65 Reset averaged wind speed to calm for level due to insufficient sub-hourly values >
threshold
Q66 Reset averaged wind speed to missing for level due to insufficient sub-hourly values
Q67 Temperature < dewpoint for level
D-10
-------
Q68 Set hourly average for variable to missing due to insufficient sub-hourly values;
exception is precipitation
Q70 Keep total precipitation for hour but not enough values for average
D-ll
-------
Appendix E. AERMET modules and subroutines
The following tables list the AERMET modules and subroutines with descriptions and a
list of subroutines or programs that call the subroutine. Note that the module FILE UNITS has
no subroutines, only file unit numbers and names.
Table E-l. List of subroutines and functions in module VTATN1
Subroutine or
Description
('silling subroutines
Function
CHECKDATES
Checks the year, month, and da\ of
a date to ensure the date is a \ alid
date.
ModuleM \l\ 1. (il'TDATES
CHECKFILE
Processes the MESSAGE,
Module ki: \D INI'1 1 JOIJ lJATH
REPORT, DEBUG, DATA,
Module I I'kFRAIR: UPPEk 1' \TH
EXTRACT, QA() 1 T. SI kPA.CE,
Module SI kl'ACE: SURF P \ 1 H
PROFILE, AERSI kl'. and
Module ONSITE: OS PATH
AERSURF2 filenames from the
Module I'UI. PBLPATH
AERMET control file
COORD
Function in read latitude or
loumiude le\t siring and com en In
a number
Module \l\l\l GETLOC
DATA DATES
( hecks ilie \car. month, dav. and
Module MAIN1: READ 6201, READ FSL,
dale of dala from upper air.
kEAD IGRA
surface, or siic-spccilic prognostic
Module SURFACE: NEW_OBS, READ ISHD
daia lo ensure a valid dale and
Module ONSITE: AUDIT, READ EXT,
u 11 In 11 the window specified b>
READOS
XDATFS for appropriate data path.
Module PBL: CHECK OBS
datai.im:
Processes ilie 1) \TA. AERSURF,
Module UPPERAIR: UPPER PATH
orAERSl kl'2 keyword lines for
Module SURFACE: SURF PATH
\l !k\1l! 1 control file
Module ONSITE: OS_PATH
Module PBL: PBL PATH
DATETIME
\\ riles dale and lime to runtimes
arni\ lo denote when AERMET
starts and stops
AERMET
GETDATES
Process XDATES keyword to get
Module UPPERAIR: UPPER PATH,
start and end dates of data
UPSTAGE2
Module SURFACE: SURF PATH, SF STAGE2
Module ONSITE: OS_PATH, OS_STAGE2
Module PBL: PBL PATH
E-l
-------
Subroutine or
Description
Calling subroutines
Function
GETFIELDS
Get fields of data from input line
Module MAIN1: GETDATES, GETLOC,
from AERMET control file
VARLIST
Module UPPERAIR: UPRANGE,
UPMODKEY
Module SURFACE: SURFRANGE,
SFTHRESH, NWS_HGTS
Module ONSITE: DELTA T HT,
OSOBSNUM. OSRANGE, OSTHRESH,
OS_VARS. OSI [EIGHTS
Module PBL. FREQ SEC, METHODS,
SI X 1 (>kS. SITECHAR, UP WINDOW,
\\ \R SIR
GETLOC
Process LOCATION keyword to
Module UPITR \lk UPPER PATH,
get station ID, coordinates, (A1T-
I P STAGE2
LST conversion, and elevation
Module SURFACE SI kf PATH,
SF ST \GE2, READ \ .\\
Module ()\SITE: OS_P \ll 1. ()S_STAGE2
Module IT.I. PBL PATH
GETUNIT
Determines wh;il file iiml or
Module I I'I'I :RAIR: UPPER PATH
standard output in w Inch in u rile
Module SI kl'ACE: SURF PATH
messages
Module ONSITE: OS_PATH
Module kf \l) INPUT: CHECK LINE,
JOIJ \>\W\
Module 1*1 >1. I'IBLPATH
HUMIDITY
I'lincUon In calculate 111111 lidi 1 \
Module SURFACE: READ ISHD
from leniperalnre and dewpnini
Module PBL: RH
LEAP^"R
Determines if a \ear is a leap \ear
\ lodule MAIN1: CHECKDATES, NUMDAYS,
DATADATES
Module SURFACE: SF PROC
Module UPPERAIR: UP_PROC
Module ONSITE: OS_PROC
Module PBL: PBL PROC
NUMDAYS
1 "unction in determine number of
Module UPPERAIR: UP_PROC, NEW_SOUND
da> s in dala period determined by
Module SURFACE: SF PROC, NEW_OBS,
\l) VI I S
READ1MIN
Module ONSITE: OS_PROC, READ EXT,
READOS
Module PBL: PBL PROC
PRESSURE
Function to calculate station or sea
Module SURFACE: READ ISHD
level pressure
Module PBL: PRESS
RANGE MOD
PROCESS RANGE keyword
Module UPPERAIR: UP RANGE
Module SURFACE: SURF RANGE
Module ONSITE: OS RANGE
START STOP
Writes AERMET processing dates
AERMET
and times to specified output file or
Module REPORTS: INPUT SUMM
device
E-2
-------
Subroutine or
Function
Description
Calling subroutines
VARLIST
Process NOMISSING keyword or
AUDIT keyword
Module UPPERAIR: UPPERLIST
Module SURFACE: SURF LIST
Module ONSITE: OS_LIST
Table E-2. Subroutines and functions in module MISC
Subroutine or
Function
Description
Calling siibroulines
CLEANUP
Closes files and deallocates arrays
ai:r\ii:t
E-3
-------
Table E-3. Subroutines and functions in module ONSITE.
Subroutine or
Description
Calling subroutines
Function
AUDIT
Audits sub-hourly or hourly data
Module ONSITE: AVG HR, OS_AUDITHR
AVGHR
Calculates hourly averages from
sub-hourly data
Module ONSITE: AVG HR
AVGWIND
Calculates hourly average wind
direction and average vector wind
speed (if requested).
Module ONSITE: AVG HR
CALCWIND
Calculates running totals of
summed wind direction for
averaging
Module ()\SI 1 li: AVG HR
CHECKHTS
Checks raw data to ensure heights
are increasing in value with
increasing levels
Module ()\SI 11!' OS_PROC
CHECKWIND
Checks hourly wind speeds auainsi
threshold; checks for zero wind
direction and wind speed above
threshold.
Module ONSITL. OS I'kOC
DELTATHT
Processes DEL l \ I I All'
keyword in AEkMI!'T control file
Module ()\SITE: OS_PATH, OS_STAGE2
FINDVAR
Function to find iiule\ of a \ anahle
in array os_audit_inde\
Module ONSITE: AVG HR
HEADER
Writes header informal urn lor
QAOUT file
Module I H'ERAIR: OS_PROC
ONSITE INIT
Initializes os\ ars fur slaue 1 or
Module ONSITE: OS PATH
siaue 2
Module PBL: PBL PROC
OSAUDTTTTR
\udils hoiuK dala
Module ONSITE: OS_PROC
OSJ'OkM
hoeesses I'OkM \T kesuord in
\l!K\ 11 "f control lile
Module ONSITE: OS_PATH, OS_TEST
OSI.IST
Process \() \1ISSI\( i keyword or
AI 1)11 keswoid lor siie-specific
data; calls V AR LIS'f
Module ONSITE: OS_PATH
OSOBSNLM
Processes OBS/HOUR keyword in
\l !KMET control file
Module ONSITE: OS_PATH
OSPATH
Processes lines from the AERMET
control lile for the ONSITE or
PROG path.
Module READ INPUT: READINP
OSPROC
Controls the reading and QA of
site-specific or prognostic data for
stage 1
AERMET
OSRANGE
Processes the RANGE keyword for
site-specific or prognostic data by
calling RANGE MOD
Module ONSITE: OS_PATH, OS_STAGE2
OSSTAGE2
Reads upper air EXTRACT or
QAOUT file header for Stage 2
Module ONSITE: OS_PROC
E-4
-------
Subroutine or
Function
Description
Calling subroutines
OSTEST
Checks that mandatory keywords
have been included and valid
processing requested
Module READ INPUT: READINP
OSTHRESH
Processes THRESHOLD keyword
in AERMET control file
Module ONSITE: OS_PATH, OS_STAGE2
OSVARS
Processes READ keyword in
AERMET control file
Module ONSITE: OS_PATH
OSFORMREAD
Checks that first READ statement
has date/time variables and
FORMAT statements do not have
syntax errors
Module ONSITE: OS_TEST
OSHEIGHTS
Processes OSHEIGHTS keyword
in AERMET control file
Module (>\SITi: OS PATH, OS_TEST
READEXT
Reads the ONSITE QAOUT l ile
Module ONSn i: OS I'ROC
READOS
Reads data file named by DA 1 \
keyword
Module ONSITE. OS I'ROC
E-5
-------
Table E-4. Subroutines and functions in module PBL
Subroutine or
Description
Calling subroutines
Function
PBLPATH
Processes lines from the AERMET
control file for the METPREP path.
Module READ INPUT: READINP
PBLPROC
Controls the processing of PBL
calculations
AERMET
PBLTEST
Checks that mandatory keywords
have been included and valid
processing requested
Module READ INPUT: READINP
PRECIP
Assign precipitation for the hour
Module I'UI. PBLPROC
PRESS
Calculates station pressure for the
hour
Module IT.I. PBLPROC
PROFILE
Assigns values to pfldata da la
type for the hour
Module PBL PI 31. PROC
READSOUND
Processes sounding for convecli\ e
mixing height and potential
temperature lapse rate calculations
Module PBL: PBL PkOC
RH
Calculates relative humidity for the
hour
Module Mil. PBL PROC
SECTORS
Processes the lino SIX K)k or
SECTOR2 from the \l K\1l 1
control file or external sin lace
charade I'M ics file
Module Mil. SI X CHARS, AERSURF
SFCCHARS
\ssiuns surface characteristics for
llie hour lor primary or secondary
site
Module Mil. WINDS
SFC 1II: \l>1 K
Writes surface header in
SURFACE lile
Module PBL: PBL PROC
siti: ( ii \k
Processes the line SI l"E_CtL\R or
SITE CI I \R2 from ihe \ERMET
control lile or external surface
characteristics file
Module PBL: AERSURF
STABILITY
( alculales critical solar elevation
nude for the hour and assigns
siahihis lor ihc hour based on
anule or \lom-Obukhov length.
Module PBL: PBL PROC
SUBSTITUTE
Interpolates temperature and/or
cloud cover for missing hours
Module PBL: PBL PROC
SUNDAT
Calculates sunrise and sunset times
and optionally calculates solar
elevation angle for all hours of the
day
Module PBL: PBL PROC
SURFYEARS
Checks to see what years are
associated with a specific set of
surface characteristics
Module PBL: AERSURF
E-6
-------
Subroutine or
Function
Description
Calling subroutines
TEMPS
Assigns temperatures for the hour
for the surface data and fills in
profile temperatures
Module PBL: PBLPROC
UPWINDOW
Processes the keyword
UAWINDOW from AERMET
control file
Module PBL: PBLPATH
VPTG
Function to calculate the potential
temperature lapse rate above the
mixing height
Module PBL: PBL PROC, CONV HT
WINDS
Assigns winds for the hour and
assigns profile values for the hour
Module 1*1 >1. I'IBLPROC
WRITESRSS
Write local and upper air station
sunrise and sunset times
Module IT>I.. 1'P.L PROC
WRITEFILES
Writes SURFACE and PROI II .1:
files
Module PBL: \>\)\. H«)C
WSTAR
Function to calculate convecm e
velocity scale w*
Module I'HL: PBLJ'kOC. ( <)\V_HT
YEARSTR
Obtains the strinu of \ ears lor the
freq sectoriki:o six r:
keyword
Module I'I'.L: PBL PATH
E-7
-------
Table E-5. Subroutines and functions in module SURFACE.
Subroutine or
Description
Calling subroutines
Function
CHECK ASOS
Checks the ASOS status of a
Module SURFACE
SF TEST, READ ISHD,
station or hour
READ CD144, READ SCRAM, READ SAM,
READ HUSWO, READ EXT, SF STAGE2
CHECK DUP
Checks to see if current
Module SURFACE
READISHD,
observation can be overwritten
READ CD144, READ SCRAM, READ SAM,
with a duplicate observation
READ HUSWO, READ EXT
DECODE 144
Decodes CD-144 overpunches
Module SURFACE
R1: \l) SCRAM
READCD144,
HEADER
Writes header information for
EXTRACT and QAOUT file
Module SI RI\CE
SFPROC
NEW OBS
Initializes/increments variables and
Module SURI ACi:
READISHD,
checks for duplicates for new
READ CD 144. Rl!
\l) SCRAM, READS AM,
observation
READ HUSWO, Ri:\l) I AT
NWSHGTS
Processes the NWS HGT ke> word
in the AERMET control file
Module PBL: PBL
Rvni
READ1MIN
Processes AERM1NUTE output in
Stage 2
\i:r\ii:t
READCD144
Processes CD144 I'oiui;ii d;il;i
Module SI Rl ACE
SFPROC
READEXT
Processes the EXTR \( "1 or
QAOUT file
Module SI RI ACE
SFPROC
READHUSWO
Processes HUSWO formal d;il;i
Module SURFACE
SFPROC
READISHD
Processes ISHD formal data
Module SURFACE
SFPROC
READSAM
Processes SAMSON formal d;il;i
Module SURFACE
SFPROC
READSCRAM
Processes SCRAM formal d;il;i
Module SURFACE
SFPROC
SFAUDIT
Audits surface data
Module SURFACE
SFPROC
SF_PR()(
Controls the reading and QA of
surface data for stage 1
AERMET
sf_si\(ii::
Reads upper air EXTRACT or
QAOUT file header for Stage 2
Module SURFACE
SFPROC
SF TEST
( hecks that mandatory keywords
Module READ INPUT: READINP
h;ivc been included and valid
piwcssiim requested
SFTHRESH
hwesscs I IIRI :SH_1MIN
kc\ word in AERMET control file
Module PBL: PBL
PATH
SFCINIT
Initializes the data type SFVARS,
formats for certain messages, valid
start/end dates for data formats,
and ASOS station information
Module SURFACE
SURFPATH
SURFLIST
Process NO MISSING keyword or
AUDIT keyword for surface data;
calls VAR LIST
Module SURFACE
SURFPATH
SURF PATH
Processes lines from the AERMET
Module READ INPUT: READINP
control file for the SURFACE path.
E-8
-------
Subroutine or
Function
Description
Calling subroutines
SURFRANGE
Processes the RANGE keyword for
surface data by calling
RANGE MOD
Module SURFACE: SURFPATH
E-9
-------
Table E-6. Subroutines and functions in module READ INPUT
Subroutine or
Function
Description
Calling subroutines
CHECKLINE
Reads AERMET control file and
checks syntax
Module READINPUT: READINP
JOBPATH
Processes lines from the AERMET
control file for the JOB path.
Module READINPUT: READINP
READINP
Main controlling subroutine to read
AERMET control file
AERMET
Table E-7. Subroutines and functions in module UK PORTS
Subroutine or
Function
Description
Calling subroutines
AUDIT_SUMM
Summarize audit results for upper
air, surface, or site-
specific/prognostic data
\ERMET
DATESLOC
Writes the processing start/end
dates and location for each path
(upper air, surface, she-specific, or
prognostic)
Modules RLPORTS: IM'l 1 SI MM
INPUT_SUMM
Writes names of inpui output liles
and processnm options foreacli
paili:
\i:rmi:t
SFCHARSUM
Writes summars of surface
characteristics forpriniar> and
secoudars site
\ermi :t
sum Fii.i:s
Writes input output filenames and
status foreacli path to report lile
Modules REPORTS: INPUT SUMM
WR]li: \IS(,
Writes messaue lile summary to
report file
AERMET
E-10
-------
Table E-8. Subroutines and functions in module UPPERAIR
Subroutine or
Description
Calling subroutines
Function
FSLVERSION
Determines the FSL data file
format version
Module UPPERAIR: READ FSL
HEADER
Writes header information for
EXTRACT and QAOUT file
Module UPPERAIR: UP_PROC
NEW SOUND
Initializes and increments variables
Module UPPERAIR: READ EXT, READ FSL,
for a new sounding
READ IGRA, READ 6201
NEWTEMP
Function to calculate new
temperature or dewpoint
Module I I'I'I :k \IR: UP_MODIFY
READ 6201
Process 6201 format upper air data
Module I I'I'I !k \IR: UP_PROC
READEXT
Read EXTRACT or QAOUT upper
air file
Module I I'lTkMR- UP_PROC
READFSL
Process FSL format upper ai r dala
Module UPPER\lk 1 P PROC
READIGRA
Process IGRA format upper air
data
Module UPPER.V1R. 1 1' I'kOC
UPAUDIT
Audits upper air data
Module I I'kERAIR: 11' I'kOC
UPMODIFY
Modifies upper air dala b\ 1)
deleting mandators le\ els. 2) sol
wind direction to <> if u md speed is
0 and 3) interpolate unssiuu
temperature and dewpoinl
Module I I'kERAIR: UP_PRO(
UPMODKEY
Processes \1( )l)IFYkeyword in
\l!K\ 11 !T control lile
Module I PPEkAIR: UPPER PATH
UPPROC
('iiiiiiols ihe icadiuu and QA of
upper air dala lor siaue 1
\ERMET
UP k \\c,i:
Processes ihe k W(¦ 1! kesword lor
Module UPPERAIR: UPPER PATH,
upper air dala In callum
I P STAGE2
k \\(ii: \l()l)
up_si\(,i::
Reads upper air EX I k \CT or
QAOUT file header lor Siage 2
Module READ INPUT: READINP
uptest
( hecks thai mandatory keywords
have been included and valid
processing requested
Module READ INPUT: READINP
UPPERINIT
1 uiiiali/cs the data type UPVARS
and formats for certain messages
Module UPPERAIR: UPPER PATH
UPPERLIST
Process NO MISSING keyword or
AUDIT keyword for upper air data;
calls VAR LIST
Module UPPERAIR: UPPER PATH
E-ll
-------
Subroutine or
Function
Description
Calling subroutines
UPPERPATH
Processes lines from the AERMET
control file for the UPPERAIR
path.
Module READ INPUT: READINP
VIRTTEMP
Function to calculate virtual
temperature
Module UPPERAIR: UP_AUDIT
E-12
-------
Appendix F. Comparison of 21DRF AI RM IT to 21112 AERMET
As part of the evaluation of 21DRF AERMET, AERMET and AERMOD were run for
the 17 evaluation databases used to promulgate AERMOD and evaluate AERMOD for each
update. AERMET version 21112 and the 21DRF version were run for each database and
AERMOD 21112 was run for each AERMET version and model results were compared. The
databases are described in Appendix B of the AERMOD model and formulation document
(EPA, 2021a). Table F-l lists the databases with summaries of sources and meteorological data.
Sources listed in gray are subject to the EPA's protocol lor determining best performing model.
Meteorological outputs were compared on an hour-by-hour basis with and without the surface
friction velocity adjustment and the AERMOD results based on the AI-RMET versions were
compared using the methodology described in Section B.4. in the AERMOD model formulation
and evaluation document (EPA, 2021a).
F-l
-------
Table F-l. AERMOD evaluation databases
Location
Stack
heights
Urban/rur
al
Terrain
Downwash
Turbulence
parameters
Site specific AERMET
inputs
Marlins
( reck
5l>. "(>. 1S i
in
Rural
( OlliplcN
Yes
III III rr . rr
loin w md.
icuipcralurc. >-42n m
w iutl (c\ er\ '0 un
Tracy
91 m
Rural
Complex
No
OVj C>w
10 and 50-400 m
(every 25 m) wind,
temperature
1 .o\ ell
145 in
Rural
(oniplc\
No
o\ n\v
Hi. 5t>. and 1 do in
wind, icuipcralurc
W'csh aco
I'Ji) in
Rural
( OlliplcN
No
o\
'D. 2 11). ^2(>. ^(><>. and
41(> in uiiid.
icuipcralurc
D.VLC
1 ill, 24 in,
46 m
Rural
Hal
Yes
("7
lusolaliou. In. 2 ' 5
and 50 in vv ind,
temperature
EOCR
1,25, 30 m
Rural
Flat
Yes
a,
4, 10, and 30 m wind,
temperature
Alaska
39.2 m
Rural
Flat
Yes
oVj aw
33 m wind,
temperature
Indianapolis
84 m
Urban
I'lal
No
o"vj aw
Station pressure, net
radiation. 10 m u iud.
icuipcralurc
Kiucaid
IX" in
Rural
I'lal
No
n\ ov
Ncl radialiou.
IllsolallOII. Id. 'O. ;|||d
5i> ill u iud.
Icuipcralurc
AGA
9.8, 14 5.
24.4 in
Rural
I'lal
Yes
None
10 m wind and
temperature
Millston
3 stacks 2l>
in i ficoni 4X
in (Sl'(>i
Rural
I'lal
Yes
None
10 m wind speed; 43.3
m wind and
Icuipcralurc
IJou line
2 slacks
X(i S" in
Rural
I'lal
Yes
None
Kin in u ii ids ;n id
leiiiperalure
IJaldxx in
' slacks
IS4 4 in
Rural
I'lal
Yes
None
In and Inn in wind.
Icuipcralurc
( lil'l\ Creek
' slacks
2u" in
Rural
\ 11 \
No
None
In in icuipcralurc. <><>
111 \\ Illd
Rnuric (iiass
ii 4<> in
Rural
I'lal
No
C5\ C7\V
I *. IIIIMIIU liciulil.
ceiling height, cloud
cover; 1, 2, 4, 8, and
16 m temperature and
wind; ctv, ctw at 2 m
1. 30 m observations removed from AERMOD profile before running AERMOD.
F-2
-------
F. 1. Meteorological data differences
As previously noted, hourly comparisons were made for all surface variables and profile
variables with a tolerance to account for rounding differences since AERMET 21DRF switched
from real to double precision for variables. Table F-2 lists the variables with tolerances.
Table F-2. Meteorological variables for comparison with tolerances.
Variable
Tolerance
Sensible heat flux
0 2 W/nr
Surface friction velocity
i) D02 m/s
Convective velocity scale
i) i)02 m/s
0 lapse rate above mixing height
i) i )D2 K in
Convective mixing height
1 m
Mechanical Mixing height
1 in
Monin-Obukhov length
i) 2 m
Surface roughness
i) in
Bo wen ratio
i)
Albedo
i)
Reference wind speed
1) 111 s
Reference wind direction
i)
Reference wind height
i) m
Reference temperature
i) 2 K
Reference temperature height
0m
Precipitation code
0
Precipitation
0 mm/hr
Relative humidity
1 %
Station pressure
2 mb
Cloud cover
0 tenths
Wind flag
Character: character strings compared
Profile height
0m
Profile top indicator
Not checked
Profile wind speed
0 m/s
Profile wind direction
0°
Profile temperature
0°C
Profile oe
0°
Profile ow
0 m/s
F-3
-------
Following are summaries of comparisons for each of the databases.
Martins Creek
o Six hours where Monin-Obukhov length differed with a range of -411 m to 1 m
for non-adjusted u*
¦ Largest difference for 1/17/199.1 hour v
o Seven hours where Monin-Obukhov length differed with a range of -302.1 to 0.6
m for adjusted u*
¦ Largest difference for both eases is 1/17/1993 hour ^
For non-adjusted and adjusted ir. difference is due to differences
in 9* for the hour and the ()* difference is due to a slight
difference in the critical angle lor the hour (9.782 for AERMET
21112 and lJKI I for AI-RMl-T 21 l)RF)
o All oilier \ ariables and hours were within tolerances for both non-adjusted and
adjusted ir
Tracy
All other \ ariables and hours were within tolerances for both non-adjusted and
adjusted ir
l.oveU
c I i\ e hours where Monin-Obukhov length differed with a range of 0.2 to 16 m for
both adjusted and non-adjusted u*
¦ Max difference of 16 m for 9/12/1988 hour 7; differences due to slight
differences in variables for calculating convective L, possibly due to the
switch from real to double precision in AERMET 21DRF.
o Precipitation missing codes differed for all hours (9999 for AERMET 21112 and
99 for AERMET 21DRF); would make no difference in AERMOD as
precipitation values matched for the two versions of AERMET.
o All other variables and hours were within tolerances for both non-adjusted and
adjusted u*
F-4
-------
Westvaco
o One hour, 6/8/1981 hour 8, differed for albedo (0.15 for AERMET 21112 and
0.16 for AERMET 21DRF). Due to adjustment of noontime albedo for hour 8
and most likely due to switch from real to double precision in AERMET 21DRF
o Two hours differed for the precipitation code with AERMET 21112 reporting 0
and AERMET 21DRF reporting as missing. Precipitation values did not differ.
o Seven hours differ for Monin-Obukho\ Icnulh for non-adjusted u* with a range
of -0.3 to 1 m
o Eight hours differ for Monin-Obukho\ Icnulh lor adjusted u* with a range of -0.3
to 1.3 m
o All other variables and hours w civ u ithin tolerances lor hoth non-adjusted and
adjusted u*
DAEC
o One hour, 7/6/1978 hour I (¦> lor a height of 5<). differs in missing values for oe.
This is due to the missing code in the raw data file not matching default missing
code for r, in AI-RYIF.T AFRMFT interprets the missing value as valid and the
AERMI-T control file should he updated to reset the missing code. While
AERMI-T 21 l)RI also does not use a reset value for the missing code, because
the input c, is neuati\ e. AI-RMI-T 21 l)RF interprets as missing.
Differences in missing codes lor precipitation. Both AERMET versions report
precipitation as missing and precipitation values are not different so no effect on
AFRMOI) results
o All other \ ariahlcs and hours were within tolerances for both non-adjusted and
adjusted ir
EOCR
o Three hours differ for the oe missing value due to missing codes (AERMET
21112 is 999 and AERMET 21DRF is -99). No effect on AERMOD as both are
interpreted as missing by AERMOD.
o All other variables and hours were within tolerances for both non-adjusted and
adjusted u*
F-5
-------
Alaska
o For both non-adjusted and adjusted u*, 11/8/1987 hour 24 differs for all
variables. This is because in the raw data file, hour 24 is reported as 11/9/1987
hour 0. AERMET 21112 ignores the hour because it is outside the XDATES
dates. Therefore, AERMET sets hour 23 values to hour 24 for the day.
AERMET 21112 converts 11/9/1987 hour 0 to 11/8/1987 hour 24 before
checking against the XDATES dates. AERMET 21112 uses the reported values
for the hour.
o Four hours for oe in the profile have different missing codes for both non-
adjusted and adjusted u*
o Nine hours for ow in the profile ha\ e different missing codes for both non-
adjusted and adjusted u*
o All other variables and hours were within tolerances for both non-adjusted and
adjusted u*
Indianapolis
o Nine hours where reference wind direction and profile wind direction differ by
0.1° in both non-adjusted and adjusted ir data Most likely due to rounding
when switching from real to double precision in AI-IIMET 21DRF.
o Two hours w here Monin-Obukho\ length differ between -0.2 and 0.2 m for both
non-adjusted and adjusted ir
Thirteen hours where r,n in the profile differ between -0.04 and 0.05 m/s
144 hours where c, in the profile differs between -0.5 and 0.5°. It appeared that
\i:k\ii:t :i 11: was rounding the input values for oe in the raw met data file to
the nearest integer
kincakl
o Set A, 8 I I ) hour 24 is missing for cloud cover and other variables that
depend on cloud cover for calculations for AERMET 21DRF but is not missing
for AERMET 21112. This is because AERMET 21112 substitutes hour 23 for
hour 24 for SURFACE data prior to PBL calculations and AERMET 21DRF
does not do that substitution. This is for both non-adjusted and adjusted u*.
o One hour in Set A where AERMET 21DRF cloud cover is 1 tenth and AERMET
21112 is 0 tenths. This is for both non-adjusted and adjust u*
o One hour where heat flux differs by 1.1 W/m2 for Set A for non-adjusted u*.
F-6
-------
o 37 hours where Monin-Obukhov length differs by 10.6 to 146.8 m for non-
adjusted u* for set A and 37 hours where Monin-Obukhov length differs by -7.2
to 84.2 m for adjusted u* for set A.
¦ Maximum differences of L due to slight difference in solar angle and 9*
for non-adjusted u* and 84.2 m for adjusted u*
o Different missing values for go and owin Set A for both non-adjusted and
adjusted u*. AERMET 21112 reports -999 and AERMET 21DRF reports 99.
Does not affect AERMOD as AERMOD sees both values as missing.
o SetB, 6/17/1981 hour 24 is missing lor AliRMI-T 21DRF and not missing for
AERMET 21112 due to the hour 23 substitution lor hour 24 for SURFACE data.
This is both for non-adjusted and adjusted u*.
o 23 hours for Set B where Monin-Obukhov length differs between -2.4 and 7.2 m
for non-adjusted u*
o 18 hours for Set B where Monin-Obul
-------
o All other variables and hours were within tolerances for both non-adjusted and
adjusted u*
Millston
o All hours have different missing codes for precipitation type code for both non-
adjusted and adjusted u*
o Two hours differ for Monin-Obukhov length for non-adjusted u*, -0.2 and 0.8 m
o Three hours differ for Monin-Obukho\ length lor adjusted u*, -0.2, 0.2, and 0.9
m
o All other variables and hours were within tolerances for both non-adjusted and
adjusted u*
Bowline
o All hours have different missing codes for precipitation type code for both non-
adjusted and adjusted ir
o Eight hours differ for Monin-Obukhov length for non-adjusted u*, -0.5 to 0.3 m
o Six hours differ for Vtonin-Ohuklun length for adjusted u*, -0.5 to 0.8 m
o All other \ariaMes and hours were within tolerances for both non-adjusted and
adjusted ir
IS:ilcl\v in
I I lM3 hour 24 hour 24 is missing for cloud cover and other variables that
depend on cloud co\ er for calculations for AERMET 21DRF but is not missing
for AI-RMI-T 21 I 12 This is because AERMET 21112 substitutes hour 23 for
hour 24 for SI RI 'ACE data prior to PBL calculations and AERMET 21DRF
does not do that substitution. This is for both non-adjusted and adjusted u*.
Monin-()bukho\ length differs for 14 hours for non-adjusted u* ranging from
-0.3 to W ni
o Monin-Obukhov length differs for 12 hours for adjusted u* ranging from -0.2 m
to 1. m
o All other variables and hours were within tolerances for both non-adjusted and
adjusted u*
F-8
-------
Clifty Creek
o Monin-Obukhov length differs for 3 hours for non-adjusted u* ranging from 0.3
to 1.3 m
o Monin-Obukhov length differs for 5 hours for adjusted u* ranging from -0.2 to 1
m.
o All other variables and hours were within tolerances for both non-adjusted and
adjusted u*
Prairie Grass
o Different missing codes for precipitation lor all hours, also results in different
precipitation codes
o Twenty-two hours differ for mechanical mixing heights for non-adjusted u*.
Differences range from -58 to 2b2 m Differences are due to a mix of site-
specific mixing heights and calculated mixing heights. AERMEI 21112 does
not smooth the mechanical heights w hen there is a mix. AERMET 21DRF does
smooth with a mix of heights
o Two hours differ for r,n with a difference of <> n| Most likely due to rounding
o All other \ariables and hours were within tolerances for both non-adjusted and
adjusted ir
F. 2. AF.RMOI) evaluations
In addition to e\aluation of meteorological data, the differences in meteorological data
were e\ aluated bused on AI-RMOI) results. For the databases listed in gray in Table F-lError!
Reference source not found., the full I -PA. protocol for determining best performing model was
used as describe in Section 1} 3 2 of the AERMOD Model Formulation and Evaluation
document. The exception to the procedure outlined in the AERMOD MFED versus the
AERMET evaluation presented here is that the ratio of the MCM to the standard error is used as
the basis of statistical significance between the two model outputs when only considering two
models. If the absolute value of the ratio is less than 1.7 then the two models are not considered
statistically different. For the databases not in gray in Table F-l, the metric compared is the
Robust Highest Concentration compared to observations. The RHC is defined by Equation 119
in Section B.3.2.1 of the AERMOD Model Formulation and Evaluation document (U.S. EPA,
2021a).
F-9
-------
Results for the databases not subject to the EPA protocol for determining best performing model
are shown in Table F-3. For most of the databases, the differences in meteorology made no
difference in RHC values. This could be due to in part, that the differing hours in the
meteorological data were not hours with observed concentrations. Two exceptions were DAEC
and Prairie Grass. DAEC differences were very small, less than 1 |ig/m3. The differences were
due to slight differences in air temperatures in the meteorological data that were within the
tolerances but given that the DAEC releases were close lo ambient temperature, the modeled
results were slightly different. For Prairie Grass, the differences u ere mostly due to the changes
in mixing heights as discussed in Section F. 1.
Table F-4 lists the Composite Performance Measure (CPM) results for the databases that
use the EPA protocol for determining best performing model and Table 1-5 shows the Model
Comparison Measure (MCM), standard error (SI 1). and ratio of MCM/SE lor the same
databases. Based on the results presented in the tables. AI-RMI-T 21112 and AERMET 21DRF
are not statistically different. The MCM \ allies are close to zero and the ratio of the MCM to
the standard error is within ±1.7.
F-10
-------
Table F-3. Observed and modeled robust highest concentrations for databases not subject to the EPA protocol for determining best
performing model.
Database
klk
Observed
\l :k\1i: r \cision
21112
21DRF
No adjust u* with
turbulence
Adjust u* no
turbulence
No adjusi ir iin
turbulence
No adjust u* with
iMihuleiice
Adjust u* no
turbulence
No adjust u* no
turbulence
Tracy
15
25
18
1 ^
25
18
13
DAEC (h=l m)
346
240
188
:::
24i)
188
222
DAEC (h=24
m)
253
84
71
"5
84
71
75
DAEC (h=46
m)
140
91
59
1
59
99
EOCR
3763
5822
5731
s:5u
5s::
5731
8250
Alaska
6
5
8
s
5
8
8
Indianapolis
6
4
4
5
4
4
5
AGA
296
NA
:<¦:
:xi
\ \
262
281
Millston
(Freon)
76
NA
«K.
|u|
\ \
96
101
Millston (SF6)
79
NA
33
35
\ \
33
35
Prairie Grass
92508"
m:57
899086
899086
F-ll
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Table F-4. Composite Performance Measure (CPM) for databases subject to the EPA protocol for determining best performing
model.
Scenario
Version
1 )atabase
Martins
Creek
Lovett
West\ aco
kincaid
Bowline
Baldwin
Clifty Creek
No adjust u*; with turbulence
21112
0.35
0.40
0.41
0.37
NA
NA
NA
21DRF
0.35
0.40
0.41
0.37
NA
NA
NA
Adjust u*; no turbulence
21112
0.31
0.53
0.60
0.56
0.50
0.45
0.49
21DRF
0.31
0.53
0.60
0.56
<>.50
0.45
0.49
No adjust u*; no turbulence
21112
0.49
0.58
0.44
0.56
0.47
0.46
0.51
21DRF
0.49
0.58
0.44
0.56
0.47
0.46
0.51
Table F-5. Model Comparison Measure (MCM), standard error (SI-) and MCM/SE ratios for databases subject to the EPA protocol
for determining best performing model
Scenario
Metric
Database
Marlins
Creek
l.ovetl
Westvaco
Kincaid
Bowline
Baldwin
Clifty Creek
No adjust u*; with
turbulence (21DRF-21112)
MCM
-1.0x10"1'
-l.OxlO"6
-l.OxlO"6
6.0x10"5
NA
NA
NA
SE
0.035
0.040
0.020
0.092
NA
NA
NA
MCM/SE
-5.0x10"5
-l.OxlO"6
-4.0x10"5
6.5x10"4
NA
NA
NA
Adjust u*; no turbulence
(21DRF-21112)
MCM
-LOxlO"6
l.OxlO"6
l.OxlO"6
2.0xl0"5
-l.OxlO"6
2.0xl0"5
3.0xl0"5
SE
0.039
0.038
0.019
0.024
0.030
0.033
0.024
MCM/SE
-5.0x10"5
l.OxlO"6
3.2xl0"4
7.5xl0"4
-l.OxlO"5
5.2xl0"4
0.001
No adjust u*; no
turbulence
(21DRF-21112)
MCM
-l.OxlO"6
l.OxlO"6
l.OxlO"6
2.0x10"5
-l.OxlO"6
2.0x10"5
3.0x10"5
SE
0.054
0.044
0.023
0.025
0.035
0.035
0.025
MCM/SE
-3.0x10"5
l.OxlO"6
l.OxlO"6
9.4x10"4
-l.OxlO"5
4.8x10"4
0.001
F-12
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United States Office of Air Quality Planning and Standards Publication No. EPA-454/D-21-001
Environmental Protection Air Quality Assessment Division December 2021
Agency Research Triangle Park, NC
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