United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park, NC 27711
EPA-454/B-96-001
October 1996
Air
& EPA
PCRAMMET User's Guide
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EPA-454/B-96-001
PCRAMMET
USER'S GUIDE
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air Quality Planning and Standards
Emissions, Monitoring, and Analysis Division
Research Triangle Park, NC 27711
October 1996
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NOTICE
The information in this document has been reviewed in its
entirety by the U.S. Environmental Protection Agency (EPA), and
approved for publication as an EPA document. Mention of trade
names, products, or services does not convey, and should not be
interpreted as conveying official EPA approval, endorsement, or
recommendation.
The following trademarks appear in this guide:
Microsoft is a registered trademark of Microsoft Corp.
Pentium and 80486 are registered trademarks of Intel, Inc.
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ACKNOWLEDGEMENTS
Many individuals have assisted with time and energy, not
only in the preparation of this User's Guide, but also in the
long-term evolution of the PCRAMMET program. Special thanks
should go to Russ Lee, Desmond Bailey, Jerry Moss, Jerry Mersch,
Joe Tikvart, and the original developer of the code, Joan Novak.
Modifications to the source code and preparation of this
user's guide were performed by Jayant Hardikar and James Paumier
of the Modeling Section, Systems Development Group (Roger Erode,
Manager) of Pacific Environmental Services, Inc., Research
Triangle Park, North Carolina. The source code to process
precipitation data was developed by Earth Tech (formerly Sigma
Research, Inc.) of Concord, Massachusetts. This effort was
funded by the U.S. Environmental Protection Agency under Contract
No. 68D30032, with Donna B. Schwede as Work Assignment Manager.
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TABLE OF CONTENTS
NOTICE i
ACKNOWLEDGEMENTS ii
TABLE OF CONTENTS iii
TABLES V
1 INTRODUCTION 1-1
1.1 OVERVIEW 1-1
1.2 DIFFERENCES FROM PREVIOUS VERSIONS 1-3
1.2.1 User Interface 1-4
1.2.2 Additional File Types 1-4
1.2.3 Output Options 1-5
2 INPUT/OUTPUT DATA 2-1
2.1. INPUT DATA 2-1
2.1.1 Mixing Height Data 2-2
2.1.2 Hourly Surface Observations 2-5
2.1.2.1 CD-144 and SCRAM Formats 2-5
2.1.2.2 SAMSON Format 2-6
2.1.3 Precipitation Data - TD-3240 Format . . . 2-9
2.2 OUTPUT FILE 2-10
3 RUNNING PCRAMMET AND THE PROGRAM INTERFACE 3-1
3.1. INTERACTIVE MODE 3-1
3.2 BATCH MODE 3-15
4 TECHNICAL DISCUSSION 4-1
4.1 TIME OF DAY 4-1
4.2 HOURLY VALUES OF MIXING HEIGHT 4-1
4.3 PASQUILL-GIFFORD STABILITY CLASSES 4-3
4.4 WINDS 4-6
4.5 TEMPERATURE 4-6
4.6 QUALITY ASSURANCE 4-7
4.7 DEPOSITION PARAMETER ESTIMATES 4-9
4.7.1 Unstable Atmosphere 4-9
4.7.2 Stable Atmosphere 4-13
4.7.3 Parameters at the Application Site . . 4-16
5 PCRAMMET PROGRAM NOTES 5-1
5.1 COMPILING AND LINKING PCRAMMET 5-1
5.2 PCRAMMET AND SCRAM 5-2
6 ERROR AND WARNING MESSAGES 6-1
6.1 WARNING MESSAGES 6-1
6.2 ERROR MESSAGES 6-3
7 REFERENCES 7-1
IV
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APPENDIX A FILE FORMATS A-1
APPENDIX B TABLES OF SITE PROPERTIES B-l
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TABLES
Table Page
2-1 Conversion of Reported Precipitation Type/Intensity to
Precipitation Codes (Liquid) 2-12
4-1 Insolation Classes as a Function of Solar Altitude for
Cloud Cover <. 5/10 4-4
4-2 Stability Classification Criteria 4-5
B-l Surface Roughness Length, in Meters, for Land-Use Types
and Seasons B-l
B-2 Albedo of Natural Ground Covers for Land-Use Types and
Seasons B-2
B-3a Daytime Bowen Ratio by Land Use and Season - Dry
Conditions B-3
B-3b Daytime Bowen Ratio by Land-Use and Season - Average
Conditions B-3
B-3c Daytime Bowen Ratio by Land-Use and Season - Wet
Conditions B-4
B-4 Average Anthropogenic Heat Flux (Qf) and Net Radiation
(Q*) for Several Urban Areas B-5
VI
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SECTION 1
INTRODUCTION
This Users Guide contains instructions for executing the
U. S. Environmental Protection Agency's PCRAMMET program on a
personal computer (PC). PCRAMMET is a meteorological
preprocessor used for preparing National Weather Service (NWS)
data for use in the Agency's short term air quality dispersion
models such as ISCST3, RAM, BLP, SHORTZ, and COMPLEX1. PCRAMMET
is not restricted for use only on a PC. It is written in
standard FORTRAN-77 code which can be compiled and run on most
platforms.
This section provides an overview of PCRAMMET and a
description of the differences between this version and previous
versions. In Section 2, the input and output files are discussed
in detail and Section 3 presents the user interface and
instructions on running PCRAMMET. Section 4 discusses the
technical aspects of the processing, while Section 5 presents
instructions on how to retrieve the program and hourly surface
observations and mixing heights from the SCRAM BBS.
1.1 OVERVIEW
The user can provide the necessary information for
processing the meteorological input data in one of two ways:
1) as an interactive prompt/response session at the PC keyboard,
or 2) with a file of responses. The response file is accessed by
including the filename as an argument on the command line.
The operations performed by PCRAMMET include:
Calculate hourly values for atmospheric stability
from meteorological surface observations;
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Interpolate twice daily mixing heights to hourly
values;
Optionally, calculate the parameters for dry and
wet deposition processes; and
Output data in the standard (PCRAMMET unformatted)
or ASCII format required by regulatory air quality
dispersion models.
The input data requirements for PCRAMMET depend on the
dispersion model and the model options for which the data are
being prepared. The minimum input data requirements to PCRAMMET
are the twice-daily mixing heights and hourly surface
observations of wind speed, wind direction, dry bulb temperature,
opaque (or total) cloud cover and ceiling height. For dry
deposition estimates, station pressure is recommended, and for
wet deposition estimates, the precipitation type and the amount
are required for those periods during which precipitation was
observed.
The surface and upper air stations should be selected for
their meteorological representativeness of the general area being
modeled. Generally this criterion corresponds to the stations
closest to the source(s) being modeled and in the same
climatological regime (e.g., coastal, mountainous, plains).
The hourly surface data can be obtained by request from the
National Climatic Data Center (NCDC) in Asheville, North
Carolina. Observations in CD-144 format on diskette for a
specific year and station should be requested. Precipitation
data can be obtained from NCDC by requesting data in TD-3240
format. An alternative to the CD-144 and TD-3240 data is the
data available on the Solar and Meteorological Surface
Observation Network (SAMSON) CD-ROMs.
The mixing height data also can be obtained by request from
the NCDC (TD-9689) in either diskette or tabular form by
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specifying 'twice daily mixing heights' for specific year(s) and
station(s).
The mixing height data and a compressed subset of the CD-144
data, with fewer weather elements, are available from the Support
Center for Regulatory Air Models (SCRAM) section on EPA's Office
of Air Quality Planning and Standards (OAQPS) Technology Transfer
Network (TTN) bulletin board system (BBS). The hourly weather
observations from SCRAM are not sufficient for use in wet
deposition or depletion calculations in ISCST3 because the SCRAM
data do not contain the present weather fields required to
determine the type of precipitation.
The output data file format depends on the final processing
option specified by the user. If the meteorological output are
to be used in an air quality model for concentration estimates
without deposition effects, then an unformatted file can be
written. However, the user has the option to write an ASCII file
directly, allowing the user to view the results without first
translating the unformatted file to an ASCII file. The formatted
ASCII file has the advantage that it is independent of the
compiler and computing platform on which it is created. If an
unformatted file is created, a formatted ASCII file can be
obtained from the unformatted file by using BINTOASC.EXE, a
program found with the ISCST3 and PCRAMMET files on the SCRAM
BBS.
For dry and wet deposition processing in ISCST3, several
additional parameters must be written to the standard PCRAMMET
output file. Due to this additional processing in ISCST3, there
is no option to write an unformatted PCRAMMET output file; the
output will always be an ASCII file.
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1.2 DIFFERENCES FROM PREVIOUS VERSIONS
Several enhancements have been incorporated into PCRAMMET
that affect the operation of the preprocessor. These
enhancements include: 1) the way the user supplies processing
information to the preprocessor (the interface), 2) an increase
in the number and type of files that can be processed, and 3)
additional options for the type of processing.
1.2.1 User Interface
In the previous version of PCRAMMET, only one type of
processing was performed and all the necessary information to
process the data was contained in the files. With the expanded
capabilities, a new user interface was necessary. With this
version of PCRAMMET, the user supplies the preprocessor with the
necessary information in one of two ways: interactive or batch.
In the interactive mode, the user responds to on-screen prompts,
with particular responses to some prompts determining subsequent
prompts, i.e., the type of data and the output requirements
determines which prompts are displayed. Once the responses are
entered, PCRAMMET begins execution. The responses to the prompts
are saved in a file for later use. A complete discussion of this
mode is provided in Section 3.1.
In the second mode, the batch mode, the user runs PCRAMMET
using command line arguments. There are two arguments on the
command line following the program name: (I) the name of the file
containing the responses to the prompts that would appear in an
interactive mode, and (2) the name of the output file. A
discussion of this mode is provided in Section 3.2.
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1.2.2 Additional File Types
In addition to the hourly surface weather observations in
the CD-144 format and the twice-daily mixing heights, several
additional file types can now be processed by PCRAMMET. Hourly
surface observations (with precipitation data, if needed)
retrieved from SAMSON CD-ROM can be used in PCRAMMET. The SAMSON
data are on a three CD-ROM set and contain radiation
measurements, weather observations and precipitation data from
the first order stations in the United States for the period
1961-1990.
PCRAMMET can now process the CD-144 hourly surface
observations that are on OAQPS' SCRAM bulletin board in the
compressed format (i.e., shorter records). Previously, the user
had to use a program to expand the SCRAM (28-character) format
to the CD-144 (80-character) format. Now, the user can use the
SCRAM files directly in PCRAMMET. This format is referred to as
the SCRAM format in the remainder of this user's guide.
The ISCST3 model can estimate, at the option of the user,
wet deposition. To make this estimate, precipitation data are
required. This version of PCRAMMET can process precipitation
data in the TD-3240 format (NCDC) or from the SAMSON CD-ROM.
Both the variable length and fixed length formats can be
processed. Generally, the data are ordered (from NCDC) in the
variable length format.
These formats are discussed in more detail in Section 2.
1.2.3 Output Options
Previous versions of PCRAMMET output an unformatted (binary)
file with hourly values of winds, temperature, stability and
mixing heights. If the user required an ASCII file, a separate
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program had to be run on the unformatted data. With this version
of PCRAMMET, the user has the option to write an ASCII output
file.
The user has the option to estimate the parameters required
for dry or wet deposition estimates in ISCST3. If the user
selects one of these options, then an ASCII output file is
created (an unformatted file is not an option) with additional
parameters for dry deposition and wet deposition estimates.
Section 3.1, item(11) describes the additional parameters need
for deposition modeling.
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SECTION 2
INPUT/OUTPUT DATA
PCRAMMET processes five input data formats: 1) CD-144 hourly
surface observations, 2) twice-daily mixing height data,
3) hourly surface observations retrieved from SCRAM, 4) hourly
surface observations, including precipitation data, archived on
CD-ROM, and 5) precipitation data (TD-3240 format).
If meteorological data are to be used as input to an air
quality model only to estimate concentration, the user has the
option of creating an unformatted (binary) or ASCII output file.
If deposition estimates are required, the output file is created
as an ASCII file.
In this section, the input data and output files are
discussed. The file structures are provided in Appendix A.
2.1. INPUT DATA
The input data requirements for PCRAMMET depend on the
dispersion model and the model options for which the data are
being prepared. For concentration estimates for which the effect
of settling and removal processes of dry and wet deposition are
not required, the necessary data are:
Wind direction
Wind speed
Dry bulb temperature
Opaque (or total) cloud cover
Cloud ceiling height
Morning mixing height
Afternoon mixing height.
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The mixing heights are based on NWS upper air soundings at 1200
GMT and 0000 GMT, respectively.
For dry deposition estimates in ISCST3, one additional
variable is needed:
Station pressure.
Station pressure is used only to compute the density of dry air.
If station pressure is missing, then a value of 1000 mb is
automatically substituted.
For wet deposition estimates in ISCST3, additional data
requirements are:
precipitation amount
present weather (for use in determining
precipitation type).
The precipitation type is determined from the present weather
codes in the hourly surface observations, which indicates whether
the type of precipitation is liquid or frozen. The hourly
precipitation amount is obtained from a separate file.
2.1.1 Mixing Height Data
Previous versions of PCRAMMET required a header record,
which is no longer needed. This record is no longer required.
However, PCRAMMET can read mixing height files that contain this
record - the record will simply be ignored. The header record,
if present, contains the following information:
NWS meteorological surface station number,
Year of surface data,
Latitude of the surface station,
Longitude of the surface station, and
Time zone of the surface station.
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The structure of the mixing height file for this version of
PCRAMMET is as follows:
Mixing height record for December 31 of the year
preceding the year of record;
Mixing height record for January 1 of the year of
record;
Mixing height record for January 2 of the year of
record;
Mixing height record for December 30 of the year of
record;
Mixing height record for December 31 of the year of
record;
Mixing height record for January 1 of the year
following the year of record (or duplicate of the
December 31 record with year, month, day changed).
The format of the mixing height data corresponds to the
format of the data that are available on the SCRAM BBS, which is
described in Appendix A. Each record contains the following
information:
Upper Air Station Number - the Weather Bureau Army Navy
(WBAN) station identification number identifying the
NWS upper air observation station used to calculate
mixing heights. The List of Upper Air Stations
available from NCDC tabulates such WBAN numbers. The
station must be representative of the site to be
modeled.
Year - the last two digits of the year of record for
the mixing height data.
Month - the month number corresponding to a given set
of mixing heights.
Day - the calendar day number corresponding to a given
set of mixing heights.
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Nocturnal Urban Mixing Height - the minimum mixing
height for a given day calculated from the 1200 GMT
upper air sounding on that day, using morning surface
temperature augmented by 5°C to account for urban
heating.
Afternoon Mixing Height - the maximum mixing height for
a given day calculated from the afternoon surface
temperatures and the 1200 GMT upper air sounding for
that day.
Each record also contains additional information on wind speed
and general weather conditions that are not processed by
PCRAMMET.
The method for calculating hourly mixing heights from the
twice daily mixing heights uses the methods suggested by
Holzworth (1972). This method interpolates the mixing heights
using the afternoon mixing height from the preceding day and both
mixing heights from the following day. For this reason, the
mixing heights for the last day of the year preceding the year of
record must be included as the first mixing height record and the
mixing heights for the first day of the year following the year
of record must be included as the last mixing height record. If
these data are not available, the data for the first and last
days of the year of record can be substituted, respectively. A
discussion of the interpolation method can be found in Section 4.
The mixing height records input to PCRAMMET must contain the
morning and afternoon mixing heights for the day being processed.
Quality checks are not performed on mixing height data input to
PCRAMMET, and so it is recommended that the user review these
data for completeness. A blank in a mixing height field is
interpreted as a zero, i.e., the mixing height is assumed to be
at the surface.
The twice daily mixing height values can be purchased from
the National Climatic Data Center (TD-9689 format) or downloaded
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from the SCRAM BBS. Note that the field position of the
afternoon mixing height in the NCDC file is not the same as the
position in the files from the SCRAM BBS (See Appendix A). The
NCDC format has the afternoon mixing height in columns 25-28 and
the PCRAMMET format has the afternoon mixing height in columns
32-35. Therefore, the user should reformat the NCDC file to
conform to the data format available on SCRAM.
2.1.2 Hourly Surface Observations
Hourly observations of surface weather can be obtained from
three sources: CD-144, SCRAM and SAMSON CD-ROM. The CD-144
format is the traditional format processed by PCRAMMET. SCRAM is
a reduced version (fewer weather variables) of the CD-144 data
and is available on the OAQPS1 TTN bulletin board. The SAMSON
data take advantage of the expanding technologies of personal
computers in the area of CD-ROM. Only one of these formats can
be processed in a single PCRAMMET run.
2.1.2.1 CD-144 and SCRAM Formats
The CD-144 format refers to the "Card Deck 144 format"
available from the NCDC. The file is composed of one record per
hour, with all weather elements reported in an 80-column card
image. The format of these records is described in the Card Deck
144 WBAN Hourly Surface Observations Reference Manual (NOAA,
1970), also available from the NCDC. Data in this file that are
checked or used by PCRAMMET includes the station number, year,
month, day, hour, cloud ceiling height, wind direction, wind
speed, dry bulb temperature, and opaque cloud cover, or total sky
cover if opaque is missing (Appendix A). The surface data files
downloaded from the SCRAM BBS contain these five weather elements
in a compressed format. The weather variables not required in
the computations are omitted and the blank fields removed to
create a 28-character record. The SCRAM format can be processed
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directly by PCRAMMET or the data may be expanded to the 80-
character records for input into PCRAMMET (See Program Notes in
Section 5).
The variables used by PCRAMMET from the CD-144 record
include the following:
Surface Station Number - the WBAN number identifying
the NWS surface observation station for which hourly
meteorological data are input to the PCRAMMET program.
Year, Month and Day of Record - identifies the year,
month and day during which the meteorological data were
observed. Only the last two digits of the year are
reported.
Hour - identifies the hour of the meteorological data
observation. Hour is based on the 24-hour clock and is
recorded as 00 through 23. Times are Local Standard
Time (LST) and are adjusted in PCRAMMET to the 01 - 24
clock in which hour 24 is the same as hour 00 of the
next day.
Ceiling Height - the height of the cloud base above
local terrain and is coded in hundreds of feet.
Wind Direction - the direction from which the wind is
blowing, based on the 36 point compass, e.g. 09=East,
18=South, 27=West, 36=North, 00=Calm.
Wind Speed - the wind speed measured in knots
(00=Calm).
Dry Bulb Temperature - the ambient temperature measured
in whole degrees Fahrenheit.
Cloud Cover - There are two cloud cover parameters,
opaque cloud cover and total cloud cover in the CD-144
and SCRAM meteorological data files. Both parameters
identify the amount of cloud cover measured in tens of
percent, e.g., 0 = clear or less than 10%, 4 = 40-49%,
-' = overcast or 100%. PCRAMMET reads the field for
opaque cloud cover.
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2.1.2.2 SAMSON Format
With the advent of CD-ROM for the personal computer, large
amounts of data can be stored in small amounts of space. NCDC
has 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, referred to as the SAMSON data. PCRAMMET
processes the data retrieved from these CD-ROMs.
PCRAMMET cannot access the data directly from a SAMSON CD-
ROM. Rather, the user must run the software provided with the
data to retrieve the station(s), period(s) of time and variables
for the site and period to be modeled. The software is a DOS-
based, interactive graphical interface and is user-friendly. The
output files are written in an ASCII file on the user's local
drive.
The software used to extract data from the CD-ROMs can
retrieve multiple years of data for a single station and save it
in the same file. However, PCRAMMET expects a maximum of one
year of data in a data file retrieved from a SAMSON CD-ROM. The
reason for this restriction is explained below.
Retrieving data from the CD-ROM is completely under the
control of the user. When data are retrieved from the CD-ROMs,
the user has the option to specify which variables to retrieve
from a list of 21 variables stored for each station. At a
minimum, the ceiling height, wind direction and speed, dry bulb
temperature and opaque cloud cover should be retrieved (to be
compatible with the data in the files on SCRAM). These variables
are sufficient for most of the models listed in Section 1, and
results in an ASCII file of about 400 Kb for one year of data.
However, if dry deposition and/or wet deposition estimates are to
be made with ISCST3, then several additional variables should be
retrieved. These are: station pressure for dry deposition
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(resulting in a file size of about 445 Kb), and present weather
and hourly precipitation amount for wet deposition (resulting in
a file size of about 537 Kb). If all of the variables are
retrieved, then a file size of about 1.2 Mb is created. When
precipitation data are retrieved, the size will vary because
precipitation amount is the last field and is filled 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).
PCRAMMET processes both of these records to obtain information
about the station (e.g., latitude and longitude) and to determine
how to process the data that follow. It is imperative that the
user not alter or delete these records. These two records begin
with the tilde character (~) . If more than one year of data are
retrieved from the CD-ROMs, these two records appear before each
year in the file. If more than one year of data are in the file,
the program will terminate with a compiler-issued error when
PCRAMMET encounters the second set of header records. The
program expects an integer value (the year), but encounters a
character value (the tilde). However, the output for the
previous year will be complete and intact. It is recommended
that the user restrict data retrieved from CD-ROM to one station
and one year per file.
PCRAMMET examines the second record to determine if the
variables retrieved from the CD-ROM are sufficient to process the
entire file according to the user's responses on how the output
is expected to be used. If there are insufficient data, then
PCRAMMET writes an error message and stops processing. The user
must either select a different processing option, or return to
the CD-ROMs and retrieve the data once again, making sure to
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retrieve all of the necessary variables to generate the
meteorological data output file.
The header records are followed by the data records. There
is one record for each hour of the time period the user
retrieved. Unlike the CD-144 format which reports the hour on
the 00-23 clock, the hour is reported on the 01 - 24 clock.
Hour 24 of a day retrieved from SAMSON corresponds to hour 00 of
the next day for CD-144 data, i.e., the time adjustment that
PCRAMMET must go through for CD-144 data is not necessary with
SAMSON.
Data stored in the SAMSON format are in different units than
found in the CD-144 data. For the output to be identical from
both input formats, PCRAMMET converts the SAMSON data to the
units that are in the CD-144 data.
2.1.3 Precipitation Data - TD-3240 Format
For wet deposition estimates from ISCST3, the dispersion
model requires the amount of precipitation as well as the
precipitation type (liquid or frozen). The precipitation type is
obtained from the present weather fields in the hourly surface
observation files (CD-144 or SAMSON) and converted to a
precipitation code that the dispersion model interprets. The
precipitation amount is not reported with the standard CD-144
data. Therefore, another file of precipitation amount is
required for wet deposition processes when CD-144 data is used.
The TD-3240 data format from NCDC contains the necessary
precipitation amount. In addition to supplying the precipitation
data when CD-144 data are processed, these data can be used to
supplement the SAMSON precipitation data in the event there are
little or no precipitation data for a station (there are about 20
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such stations which are noted in the SAMSON online help), or if
precipitation was not retrieved from the CD-ROMs.
The TD-3240 data as received from NCDC are usually in a
variable-length format. In this format, precipitation data for
the entire day is stored on one record, and only for those hours
during which precipitation was reported. A fixed-length format
is also available in which one record contains the precipitation
amount for one hour. As with variable-length files, data are
stored only for those days and hours for which precipitation was
reported. PCRAMMET can process both formats. For variable-length
formats, the preprocessor converts the data to a fixed-length
format, writes the results to a scratch file and uses the scratch
file for processing. The scratch file is deleted at the end of
the run.
Precipitation is reported in inches and hundredths of an
inch in the TD-3240 format. These units are converted to
millimeters for use in the ISCST3 dispersion model.
2.2 OUTPUT FILE
The first record in the output file from PCRAMMET contains a
file identification record followed by one record for each day in
the year. The file identification record contains the year of
record for the surface meteorological data, the surface station
identification number, the year of record for the mixing height
data, and the upper air station identification number.
If the user specifies that no (dry or wet) deposition
estimates are to be performed with the output data set, then the
user has the option of creating an unformatted (binary) or ASCII
output file. The binary output from PCRAMMET consists of one
record with the year, month, and the Julian day followed by 24
values of stability class, wind speed, temperature, flow vector,
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randomized flow vector, and rural and urban mixing heights. The
ASCII file contains the same information except that each hour is
written as a separate record.
The four values on the file identification record and the
year, month, Julian day and stability class record are written as
FORTRAN integer variables. All other values on the daily records
are FORTRAN real number variables. See Appendix A for a
description of the arrangement of the variables on each of the
daily records.
If an unformatted file is written, all records on the output
file are written with an unformatted FORTRAN write statement.
Thus, the resulting output file structure will be dependent upon
the FORTRAN compiler used to create the PCRAMMET executable. As
a result, to maintain compatibility with the unformatted file,
the models requiring its use must also have been created using
the same compiler. Most executables on the SCRAM BBS requiring
the use of the PCRAMMET unformatted output file have been created
using the Microsoft or Lahey FORTRAN compiler.
For dry deposition estimates, three additional fields are
written to the output file: surface friction velocity (u,) ,
Monin-Obukhov length (L), and surface roughness length (z0) .
Stull (1988) provides a good discussion of these parameters. The
output file is in ASCII only.
For wet deposition, the three parameters for dry deposition
plus two additional parameters are written: precipitation type
(which is based on the present weather codes in the hourly
surface observation file) and the precipitation amount. The
output is in ASCII only. Table 2-1 below shows how the reported
precipitation type and intensity are converted to the
precipitation codes that are written to the output file.
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TABLE 2-1
Conversion of Reported Precipitation Type/Intensity to
Precipitation Codes (Liquid)
Precipitation Code
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Type
Rain
Rain
Rain
Rain Showers
Rain Showers
Rain Showers
Freezing Rain
Freezing Rain
Freezing Rain
(not used)
(not used)
(not used)
Drizzle
Drizzle
Drizzle
Freezing Drizzle
Freezing Drizzle
Freezing Drizzle
Intensity
Light
Moderate
Heavy
Light
Moderate
Heavy
Light
Moderate
Heavy
.
.
-
Light
Moderate
Heavy
Light
Moderate
Heavy
2-12
-------
TABLE 2-1, continued
Conversion of Reported Precipitation Type/Intensity to
Precipitation Codes (Liquid)
Precipitation Code
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
Type
Snow
Snow
Snou
Snow Pellets
Snow Pellets
Snow Pellets
(not used)
Ice Crystals
(not used)
Snow Showers
Snow Showers
Snow Showers
(not used)
(not used)
(not used)
Snow Grains
Snow Grains
Snow Grains
Ice Pellets
Ice Pellets
Ice Pellets
(not used)
Hail
(not used)
(not used)
Small Hail
(not used)
Intensity
Light
Moderate
Heavy
Light
Moderate
Heavy
.
*
.
Light
Moderate
Heavy
.
.
_
Light
Moderate
Heavy
Light
Moderate
Heavy
.
*
.
.
*
-
* Intensity not reported for ice crystals, hail and small hail.
2-13
-------
SECTION 3
RUNNING PCRAMMET AND THE PROGRAM INTERFACE
The user supplies the necessary processing information to
PCRAMMET in one of two ways: 1) interactively, responding to
program prompts, or 2) in a batch mode using a file that contains
the responses to the prompts that would appear during an
interactive session (referred to as a response file). In this
section, these two methods of providing information to PCRAMMET
are presented. It is recommended that PCRAMMET be run in the
interactive mode until the user gains familiarity with the
various prompts and is comfortable constructing or modifying
response files.
3.1. INTERACTIVE MODE
The user can enter the information needed by PCRAMMET by
responding to a series of screen prompts from PCRAMMET.
Particular responses will affect subsequent prompts. In other
words, not every PCRAMMET run will have the same set of prompts.
PCRAMMET records the users responses in an annotated file named
INPUTS, which can be used to run PCRAMMET with command line
arguments, as discussed in Section 3.2.
To start the interactive mode, the user types PCRAMMET at
the DOS prompt followed by pressing ENTER. The following is the
sequence of prompts that appear on screen and a description of
the expected responses. Note that not all prompts will be
displayed for every run of PCRAMMET. The prompts depend on what
the output will be used for and the data formats to be used.
Some of the prompts discussed below have been grouped together
because either (1) all will appear or (2) none will appear
(again, depending on previous responses). The responses can be
entered in upper or lower case - PCRAMMET converts many of the
3-1
-------
character responses to upper case for correct processing. When a
filename is entered, it must conform to the computer platform's
file naming conventions. On a DOS platform, this is an optional
path followed by an 8-character file plus 3-character extension.
The maximum length for a path\filename.extension is 40
characters. PCRAMMET attempts to catch any errors the user makes
when entering responses. A message is displayed and the program
prompts for a new response. If a valid, but incorrect, response
is entered, simultaneously pressing the 'control1 and 'C' or
'control' and 'break' keys simultaneously will return the user to
the DOS prompt.
The prompts and possible or expected responses are:
1) Will you be making any dry or wet deposition calculations?
None / Dry / Wet :
The user can respond with NONE (N), DRY (D) or WET (W) ,
corresponding to no deposition, dry deposition, or wet
and dry deposition, depending on the dispersion model
application. The first letter of the response also can
be used here.
2) Enter the OUTPUT filename:
The name of the file where the output is to be written
is entered at this prompt.
3) Enter the output file type:
Unform / Ascii :
This prompt is seen only if NONE (or N) is the response
to the type of calculation (in (1) above). Valid
responses are UNFORM (or U) and ASCII (or A). UNFORM
will produce the unformatted file generated by previous
versions of PCRAMMET.
3-2
-------
4) Enter MIXING HEIGHT data filename:
The name of the file containing the twice-daily mixing
heights is entered at this prompt. If the file does
not exist (e.g., the user misspells the name), PCRAMMET
immediately displays an error message and prompts for
the filename again.
5) Enter the HOURLY SURFACE DATA filename:
The name of the file containing the hourly weather
observations is entered at this prompt. If the file
does not exist (e.g., the user misspells the name),
PCRAMMET immediately displays an error message and
prompts for the filename again.
6) Enter surface data format:
GDI44 or SAMSON or SCRAM :
Valid responses are CD144, SCRAM and SAMSON. These
formats are explained in detail in Section 2. CD144
corresponds to the format that previous versions of
PCRAMMET have used, SCRAM refers to the format
available on OAQPS1 TTN bulletin board, and SAMSON
refers to data the user has retrieved from CD-ROM.
7) Enter the latitude of the surface station in decimal degrees
- positive for stations north of the equator:
Enter the longitude of the surface station in decimal degrees
- positive for stations *WEST* of Greenwich:
Enter the time zone of the surface station
- positive for stations WEST of Greenwich:
These three prompts are seen only if the surface data
format is CD144 (in (6) above) or SCRAM. The user
3-3
-------
enters the latitude and longitude, in decimal degrees,
that correspond to the location where the hourly
surface observations were taken. For the output using
CD-144 and SCRAM input data to agree with the output
using SAMSON input data, the latitude and longitude
should be specified with four or more digits after the
decimal.
If the user is unsure about the correct values to enter
here, the latitude, longitude, and time zone for all
sites on the SCRAM BBS are available from the
Meteorological Data Main Menu. Select Station
Lat/Long Values Search from this menu and enter the
station number or station name when asked to enter a
search key. Alternatively, NCDC has available a manual
of latitude and longitude by station name and WBAN
number. SAMSON data contain this information within
the file, so PCRAMMET does not request it. Note: These
prompts/responses and the station and date information
in SAMSON data files replace the initialization record
that appeared in the mixing height file for previous
versions of PCRAMMET.
8) SAMSON data may already contain hrly precip
Do you want to supplement with TD-3240 data?
Yes / No :
This prompt is seen only if the response to the type of
calculation (in (1) above) is WET and the surface data
format is SAMSON (in (6) above). Valid responses are
YES (or Y) and NO (or N). If the user answers with
YES, the user specifies the filename of TD-3240
precipitation data to use (in (9) below) in the event
the SAMSON data retrieved from CD-ROM lacks
precipitation data.
3-4
-------
9) Enter HOURLY PRECIP DATA filename:
This prompt is seen only if the response to the type of
calculation (in (1) above) is WET and the surface data
format (in (6) above) is CD144, oj: if the SAMSON data
are to be supplemented (in (8) above). The name of the
file containing the precipitation data in NCDC's TD-
3240 format is entered at this prompt. If the file
does not exist (e.g., the user misspells the name),
PCRAMMET immediately displays an error message and
prompts for the filename again.
10) Enter precipitation file format
Variable or Fixed:
This prompt is seen only if the response to the type of
calculation (in (1) above ) is WET. Valid responses
are VARIABLE (or V) and FIXED (or F). These terms are
explained in Section 2.1.3.
11) For deposition, site characteristics are needed
If the response to the type of calculation (in (1)
above) is DRY or WET, then PCRAMMET prompts the user
for properties representative of the measurement and
application sites. These properties are required for
dry and wet deposition calculations that are performed
with the ISCST3 model. For many of these site
characteristics, if the user enters an invalid value
(e.g., a roughness length less than zero), a message is
shown on the screen and the prompt is redisplayed.
The following are more detailed explanations of the
information required to respond to the prompts.
Minimum Monin-Obukhov Length - Stable Conditions fmeters)
The Monin-Obukhov length is a measure of atmospheric
stability. It is negative during the day when surface
3-5
-------
heating results in an unstable atmosphere and positive at
night when the surface cools (stable atmosphere). Values
near zero indicate very unstable or stable conditions
(depending on the sign). In urban areas during stable
conditions, the estimated value of L may not adequately
reflect the less stable boundary layer. Hanna and Chang
(1991) point out that mechanical turbulence generated by
obstacles (buildings) in urban areas will tend to produce a
"more neutral" surface layer than that over an unobstructed
site. They suggest that a minimum value of L be set for
stable hours in order to simulate this effect. Using an
approximate relation between obstacle height and the zone of
flow affected by an obstacle, they suggest the following
minimum values for several urban land use classifications:
agriculture (open) 2m
residential 25m
compact residential/industrial 50m
commercial (19-40 story buildings) 100m
(> 40 story buildings) 150m
Anemometer Height (meters)
The height at which the winds were measured. For data
observed at airports, this value can range from about 6
meters (20 feet) to 9 meters (30 feet). The user must
determine the anemometer height. A good source is the set
of Local Climatological Data Annual Summaries, available
from NCDC. These summaries contain information about the
instrumentation at the end of each station's data entry for
the entire period of record.
Surface Roughness Length - Measurement Site (meters)
The surface roughness length is a measure of the height of
obstacles to the wind flow. It is not equal to the physical
dimensions of the obstacles, but is generally proportional
to them. Typical values for a range of land-use types as a
function of season are listed in Table B-l. At this prompt,
3-6
-------
the user enters a value representative of the site where the
winds were measured, e.g., an airport.
Surface Roughness Length - Application Site (meters)
At this prompt, the user enters a roughness length
representative of the site where the meteorological output
are to be applied. The discussion above for the roughness
length at the measurement site also applies here.
Noon-time Albedo
Noon-time albedo is defined as the fraction of the incoming
solar radiation that is reflected from the ground when the
sun is directly overhead. Adjustments are made
automatically within PCRAMMET for the variation in the
albedo with solar elevation angle. A range of values is
given in Table B-2 as a function of several land-use types
and season.
Bowen Ratio
The Bowen ratio is a measure of the amount of moisture at
the surface. The presence of moisture at the earth's
surface alters the energy balance, which in turn alters the
sensible heat flux and Monin-Obukhov length. A range of
values is given in Tables B-3a, 3b and 3c as a function of
land-use types, seasons and moisture conditions.
Anthropogenic heat flux (W/ro2)
The anthropogenic heat flux can usually be neglected (set
equal to zero) in areas outside highly urbanized locations.
However, in areas with high population densities or high
energy use, this flux may not always be negligible. Oke
(1978) presents estimates of population density and per
capita energy use for 10 cities and obtains a heat flux for
each. Summertime values are typically 50% of the mean,
while wintertime values are about 150% of the mean in the
3-7
-------
colder climates. Table B-4 provides guidance for several
urban areas.
Fraction of Net Radiation Absorbed at the Ground
The flux of heat into the ground during the daytime is
parameterized as a fraction of the net radiation. Values
suggested by Oke (1982) are:
rural 0.15
suburban 0.22
urban 0.27
The three types of calculation (NONE, DRY and WET) and two
hourly surface observation formats (CD-144 and SAMSON) yield
six combinations of prompts (others are possible, depending
on responses, but these are the main categories that have an
affect on subsequent prompts). The following tables can be
referred to by the user to assist in which prompts to expect
for the six combinations. The prompts and responses when
using SCRAM data would be the same as for CD-144 data except
for the response to the "Surface Data Format" prompt.
3-8
-------
NO DEPOSITION, CD-144 DATA
Program Prompt
User Response
Comments
Calculation Type
Output Filename
Output File Type
Mixing Height Filename
Hourly Surface Obs. Filename
Surface Data Format
Station Latitude
Station Longitude
Station Time Zone
NONE (or N)
output_filename
UNFORM (or U) or ASCII (or A)
mi x i ng_he i gh t_fiIename
surface_data_fiIename
CD 144
station latitude
station longitude
time zone (5=Eastern, 6=Central,
7=Mountain, 8=Pacific)
Output cannot be used for
deposition estimates in ISCST3
Does not appear in response file
Data from SCRAM can be used -
respond with SCRAM
decimal degrees
decimal degrees
integer
NO DEPOSITION, SAMSON DATA
Program Prompt
User Response
Comments
Calculation Type
Output Filename
Output File Type
Mixing Height Filename
Hourly Surface Obs. Filename
Surface Data Format
NONE (or N)
output_filename
UNFORM (or U) or ASCII (or A)
mixing_height_filename
surface_data_fiIename
SAMSON
Output cannot be used for
deposition estimates in ISCST3
Does not appear in response file
latitude, longitude and time zone
are in the data file
3-9
-------
DRY DEPOSITION, CD-144 DATA
Program Prompt
User Response
Comments
Calculation Type
Output Filename
Mixing Height Filename
Hourly Surface Obs. Filename
Surface Data Format
Station Latitude
Station Longitude
Station Time Zone
Minimum Monin-Obukhov Length
Anemometer Height
Surface Roughness Length -
Measurement Site
Surface Roughness Length -
Application Site
Noontime Albedo
Bowen Ratio
Anthropogenic Heat Flux
Fraction of Net Radiation
Absorbed at the Ground
DRY (or D)
output_filename
mixing_height_filename
surface_data_filename
CD 144
station latitude
station longitude
time zone (5=Eastern, 6=Central,
7=Mountain, 8=Pacific)
Output cannot be used for wet
deposition estimates in ISCST3
ASCII is only output file type;
does not appear in response file
SCRAM data lack station pressure;
a default of 1000 mb is used if
SCRAM data are used
decimal degrees
decimal degrees
integer
meters
meters
meters
meters
between 0.0 and 1.0
0.5 = very moist, 10.0 = very dry
0 for rural, 100 for large urban
0.15 for rural, 0.27 for urban
3-10
-------
DRY DEPOSITION, SAMSON DATA
Program Prompt
User Response
Comments
Calculation Type
Output Filename
Mixing Height Filename
Hourly Surface Obs. Filename
Surface Data Format
Minimum Monin-obukhov Length
Anemometer Height
Surface Roughness Length -
Measurement Site
Surface Roughness Length -
Application Site
Noontime Albedo
Bowen Ratio
Anthropogenic Heat Flux
Fraction of Net Radiation
Absorbed at the Ground
DRY (or D)
output_filename
mixing_height_filename
surface_data_filename
SAMSON
Output cannot be used for wet
deposition estimates in ISCST3
ASCII is only output file type;
does not appear in response file
meters
meters
meters
meters
between 0.0 and 1.0
0.5 = very moist, 10.0 = very dry
0 for rural, 100 for large urban
0.15 for rural, 0.27 for urban
3-11
-------
WET DEPOSITION, CD-144 DATA
Program Prompt
User Response
Comments
Calculation Type
Output Filename
Mixing Height Filename
Hourly Surface Obs. Filename
Surface Data Format
Station Latitude
Station Longitude
Station Time Zone
Hourly Precipitation Filename
Precipitation File Format
Minimum Monin-Obukhov Length
Anemometer Height
Surface Roughness Length -
Measurement Site
Surface Roughness Length -
Application Site
Noontime Albedo
Bowen Ratio
Anthropogenic Heat Flux
Fraction of Net Radiation
Absorbed at the Ground
WET (or W)
output_filename
mi x i ng_he i gh t_fiIename
surface_data_fiIename
CD 144
station latitude
station longitude
time zone (5=Eastern, 6=Central,
7=Mountain, 8=Pacific)
prec i p_data_f i I ename
VARIABLE (or V) or FIXED (or F)
ASCII is only output file type;
does not appear in response file
SCRAM data lack present weather;
do not use the SCRAM format for
wet deposition in ISCST3
decimal degrees
decimal degrees
integer
meters
meters
meters
meters
between 0.0 and 1.0
0.5 = very moist, 10.0 = very dry
0 for rural, 100 for large urban
0.15 for rural, 0.27 for urban
3-12
-------
WET DEPOSITION, SAMSON DATA
Program Prompt
User Response
Comments
Calculation Type
Output File Name
Mixing Height Filename
Hourly Surface Obs. Filename
Surface Data Format
Supplement SAMSON Precipitation
Data with TD-3240?
Hourly Precipitation Filename
Precipitation File Format
Minimum Monin-Obukhov Length
Anemometer Height
Surface Roughness Length -
Measurement Site
Surface Roughness Length -
Application Site
Noontime Albedo
80wen Ratio
Anthropogenic Heat Flux
Fraction of Net Radiation
Absorbed at the Ground
WET (or V)
output_filename
mi x i ng_hei ght_f iIename
surface_data_filename
SAMSON
YES (or Y) or NO (or N)
prec i p_data_f iIename
VARIABLE (or V) or FIXED (or F)
ASCII is only output file type;
does not appear in response file
prompted only if using TD-3240 as
supplemental data
prompted only if using TD-3240 as
supplemental data
meters
meters
meters
meters
between 0.0 and 1.0
0.5 = very moist, 10.0 = very dry
0 for rural, 100 for large urban
0.15 for rural, 0.27 for urban
3-13
-------
When the user responds to the final prompt, PCRAMMET begins
processing the data. The current year/month/day are displayed as
each day is processed. Depending on the system used, the runtime
for PCRAMMET is from 35 seconds on a 80486 33 MHz system to 10
seconds on a 90 MHz Pentium. On completion, the following
message is displayed:
Your responses to the program prompts have been written to the file
"INPUTS."
See the file PCRAM.LOG for a review this run
The message indicates that the responses provided during the
interactive input (excluding the output filename) can be found in
the file "INPUTS." This file can be used for subsequent runs of
PCRAMMET (as described below). The second line indicates that a
summary of the run is located in the file PCRAM.LOG. This file
is an ASCII file that can be viewed with any text editor or typed
to the screen.
In addition, if PCRAMMET wrote any warning messages to the
log file, then the following message appears:
*** Warning messages were generated by PCRAMMET and are in PCRAM.LOG
The message indicates that nonfatal messages generated by
PCRAMMET are located in PCRAM.LOG. Messages such as rural mixing
heights less than 10 meters and warnings about multiple forms of
precipitation are written to this file.
If a fatal error occurs, PCRAMMET writes one message in
PCRAM.LOG that identifies the source of the error. The following
message is displayed on the screen, and PCRAMMET stops
processing:
3-14
-------
****** FATAL ERROR ******
PROGRAM TERMINATED
See the Output File PCRAM.LOG for Details
The message should provide sufficient information for the user to
identify and correct the problem and restart PCRAMMET. Examples
of fatal errors are: 1) a file not found, and 2) incorrect
specification of a file format (e.g., indicating the surface data
are CD144 when the file is the SAMSON format). A listing of
error messages is located in Section 6.2.
Whether PCRAMMET successfully or unsuccessfully completes
processing the data, the user should review PCRAM.LOG to insure
the data were processed correctly and as expected.
3.2 BATCH MODE
PCRAMMET records the users responses during the interactive
session in an annotated file named INPUTS. This file is referred
to as a response file. The only response that is not written to
this file is the output filename. If the user expects to rerun
PCRAMMET with these or similar responses, then the user should
save INPUTS, e.g. by renaming the response file. If the file is
not saved in some manner, then the next run of PCRAMMET
overwrites the file without any opportunity to save or rename the
file.
PCRAMMET can use this file, or a modified version of it, as
one of the command line arguments to run the preprocessor in
batch mode. In addition to the program name, the user supplies
two filenames: the file with the responses to the prompts that
the program would display during an interactive session
(response_file) and the file to which the output is written
(output_file). To start PCRAMMET in this manner, type:
PCRAMMET response_file output_file
3-15
-------
followed by pressing ENTER. If the user only supplies one
filename or more than two, then the following message appears on
the screen and PCRAMMET stops:
COMMAND ERROR: PCRAMMET [input_control output_for_model]
optional
If the command line doesn't have an error, PCRAMMET
processes the records in the response file as if they were
entered interactively, and assuming no errors are encountered,
processes the meteorological data. The current year/month/day
are displayed as each day is processed. On successful completion
of the processing, PCRAMMET displays the following message:
See the file PCRAM.LOG for a review this run
If any warning messages were issued, the following message will
also appear, indicating that nonfatal messages generated by
PCRAMMET are located in the log file:
*** Warning messages were generated by PCRAMMET and are in PCRAM.LOG
Any errors in the response file will prevent PCRAMMET from
processing the remainder of the response file as well as the
input meteorological data. PCRAMMET displays the following
message and stops:
****** FATAL ERROR ******
PROGRAM TERMINATED
See the Output File PCRAM.LOG for Details
Whether PCRAMMET successfully or unsuccessfully completes
processing the data, the user should review PCRAM.LOG to insure
the data were processed correctly and as expected.
3-16
-------
SECTION 4
TECHNICAL DISCUSSION
In this section the technical issues regarding the data
processing are discussed. These issues include simple data
manipulation (e.g., converting data to the correct units) and
simple quality assurance procedures, methods for computing the
hourly mixing heights and atmospheric stability, and the
theoretical basis for estimating the deposition parameters.
4.1 TIME OF DAY
When reading the CD-144 format, PCRAMMET skips the first
hourly record of data in the year because the 24-hour period for
the regulatory models starts with the l-hour period ending 0100
LST and the observations in CD-144 files begin with the
observation reported at 0000 LST (equivalent to 2400 LST of the
previous day). Sequential reading of the remaining data
automatically makes this adjustment for each succeeding day.
Meteorological data for the last hour in the year are assumed
equal to that for the next to the last hour because the data for
a day always ends with hour 23. Data on the SAMSON CD-ROM begin
with hour 1 and end with hour 24, eliminating the need to skip a
record. However, the last hour of the year may contain missing
data and are processed similarly to the CD-144 formatted data.
4.2 HOURLY VALUES OF MIXING HEIGHT
The processing of hourly mixing heights requires: 1)
morning and afternoon estimates of mixing heights; 2) the local
standard time of sunrise and sunset; and 3) hourly estimates of
stability. Morning and afternoon mixing height estimates are
based on the method of Holzworth (1972). Two interpolation
schemes are used to estimate hourly mixing heights, one for rural
4-1
-------
sites and the other for urban sites. Both estimates are included
in the PCRAMMET output file. The time of sunrise and sunset are
calculated within PCRAMMET based on the date, latitude,
longitude, and time zone, using known earth-sun relationships
(e.g., Sellers (1965)). The values for latitude, longitude, and
time zone for a particular station are required input to PCRAMMET
when using the CD-144 formatted data. SAMSON data contain this
information in the first record of the file, making it
unnecessary to enter this information. Estimates of hourly
stability class are based on Turner's (1964) method using time of
day, surface wind speed, and observations of cloud cover and
ceiling.
To calculate an hourly mixing height, the procedure uses the
maximum mixing height (MAX) from the previous day (i-1) , the
computation day (i) and the following day (i+1) and the minimum
mixing height (MIN) for days (i) and (i+1) . For urban sites
between midnight and sunrise, under neutral stability (i.e.,
Class D) , the interpolation is between MAX^a at sunset on the
previous day, and MAXA at 1400 LST on the current day. For
stable conditions (i.e., Class E or F) , the value for the minimum
mixing height (MIN) is used. Between sunrise and 1400 LST, if
the stability was classified as neutral in the hour before
sunrise, the earlier interpolation between MAX^ and MAXX is
continued; if the hour before sunrise was classified as stable,
the interpolation is between MINi and MAX^ For the period 1400
LST to sunset, the value for MAXi is used. During the hours
between sunset and midnight under neutral stability, the
interpolation is between MAXi at sunset and MAXi+1 at 1400 LST the
next day; if the stability is stable, the interpolation is
between MAXi at sunset and MINi+1 at midnight.
For rural sites between midnight and sunrise, the
interpolation is between MAXi-! at sunset on the previous day and
at 1400 LST on the current day. During the hours between
4-2
-------
sunrise and 1400 LST, if stability was classified as neutral in
the hour before sunrise, the earlier interpolation between MAX^
and MAXi is continued; if the hour before sunrise was classified
as stable, the interpolation is between 0 and MAXi. For the
period 1400 LST to sunset, the value for MAXi is used. During
sunset to midnight, the interpolation is between MAXi at sunset
and MAXi+: at 1400 LST the next day.
4.3 PASQUILL-GIFFORD STABILITY CLASSES
PCRAMMET recognizes seven stability classes. The first six
categories correspond to Pasquill's (1974) classifications (A-F).
The seventh category corresponds to the 'dashes' in the original
classification by Pasquill and indicates a strong, ground-based
nocturnal temperature inversion with non-definable wind flow
conditions. Standard EPA practice in regulatory dispersion
modeling is to restrict temporal changes in stability class to no
more than one per hour. The stability smoothing procedure in
PCRAMMET implements this.
In the urban mode, stability categories 5, 6, and 7 (E, F,
and G) are treated as category 4 (i.e., D or neutral). Also, it
should be noted that most regulatory models treat rural stability
class G (7) as F (6). For daytime cases, the appropriate
insolation class is selected by means of the Turner (1964)
objective method using cloud cover, ceiling height, and solar
elevation as indicators. This method assigns net radiation
indices, using the criteria shown in Table 4-1, for cases where
the total cloud cover is less than or equal to 5/10. If the
cloud cover is greater than 5/10, but less than 10/10 (overcast),
the insolation class is reduced by one category when the ceiling
height is between 7000 and 16000 feet and by two categories for
ceilings less than 7000 feet. For a cloud cover of 10/10 (i.e.,
overcast), the insolation class is reduced by one category when
the ceiling height is greater than 16000 feet and by two
4-3
-------
categories for ceilings between 7000 and 16000 feet. For
ceilings below 7000 feet and 10/10 cloud cover, a net radiation
of 0 is defined and neutral stability is specified. With the
exception of the 10/10 low cloud cases, the net radiation index
is never reduced below 1, or 'weak1. The final stability
classification criteria is selected from Table 4-2 and Turner's
insolation classes from Table 4-1.
TABLE 4-1
Insolation Classes as a Function of Solar
Altitude for Cloud Cover < 5/10 *
Solar elevation Insolation Net Radiation
angle (a) class Index
0°
15°
35°
60°
5/10 cloud cover, see text
4-4
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TABLE 4-2
Stability Classification Criteria
Daytime Insolation
Surface
Wind
Speed
(knots)
< 1
2
3
4
5
6
7
8
9
10
11
i!2
Strong
1
1
1
1
1
2
2
2
2
3
3
3
Moderate
1
2
2
2
2
2
2
3
3
3
3
4
Slight
2
2
2
3
3
3
3
3
3
4
4
4
Weak
3
3
3
4
4
4
4
4
4
4
4
4
Overcast
4
4
4
4
4
4
4
4
4
4
4
4
Nighttime
2:5/10
Cl oud
6
6
6
5
5
5
4
4
4
4
4
4
< 5/10
Cloud
7
7
7
6
6
6
5
5
5
5
4
4
4-5
-------
4.4 WINDS
Hourly wind direction data input to PCRAMMET are tested for
calms (coded as 0° by the NWS; note that a north wind is coded as
360°), and if present, the wind direction from the previous hour
is substituted. PCRAMMET converts all wind directions to flow
vectors (in the range of 0-360°) by adding or subtracting 180°.
These flow vectors are then randomized by adding a random integer
number of azimuth degrees between -4° and +5°. This procedure is
applied to remove the directional bias introduced into the NWS
data because they are reported to only the nearest 10°. The
randomization gives the flow vector an equal probability of
occurring anywhere within the 10° sector and so incorporates the
natural fluctuations of this parameter. A standard set of 8784
random numbers is used.
Hourly wind speed data in the CD-144 format are converted
from the NWS units of knots to meters per second (ms"1) . Wind
speeds in the SAMSON data are already in meters per second (to
the nearest 1/10 m s"1) , but are converted back to knots then to
meters per second to insure that the results in the output files
from the two input data formats are identical. Wind speeds below
1.0 ms"1 (calms included) are set to 1.0 m s"1 before computations
are made in PCRAMMET.
4.5 TEMPERATURE
For the CD-144 data, hourly ambient temperature data are
converted from the NWS reporting units of degrees Fahrenheit (°F)
to Kelvin (K). For SAMSON data, the reporting units are degrees
Celsius (°C) and are converted to Kelvin.
4-6
-------
4.6 QUALITY ASSURANCE
Data may be missing from any of the sources for certain
hours, days, or even months. PCRAMMET performs a limited check
on the data, depending on the source and type.
Quality assurance of the CD-144 surface data file beginning
with the year, month, day and hour are checked for consistency
and completeness. If one or more hourly records are missing, or
are out of order, then the program terminates after printing
appropriate error messages. PCRAMMET does not verify the station
identification number.
For the CD-144 format, blanks in the data fields indicate
missing data. In PCRAMMET, the data are read as character
strings and then checked for blanks. If a blank is encountered,
then a message is written to the log file indicating which
variable is missing and the date and time it is missing. A
missing data code is entered for that variable for that hour.
Next, the year, month, and day of the hourly surface
observations are compared to the corresponding date from the
mixing height file. If these two files are not synchronized,
then PCRAMMET stops after writing an error message (with the
month and day of the mismatch) to the log file. PCRAMMET reads
24-hour blocks of data and performs only one check on the month
and day.
Hourly surface observations obtained from the SCRAM BBS are
in a compressed format, i.e., only selected variables are
reported and the record length is shortened. The SCRAM data can
be used directly in PCRAMMET or it can be expanded using a
program such as MET144, which is provided on the SCRAM BBS. The
MET144 program provides an option to expand the SCRAM format to
the CD-144 format. The program also provides an option to list
4-7
-------
all the missing data, with the date and time of occurrence, that
appear in the SCRAM formatted surface data file.
Prior to processing the SAMSON data, PCRAMMET checks to
verify that the necessary meteorological variables were retrieved
from CD-ROM for the intended modeling option (no/dry/wet
deposition). If there are insufficient data, a message is
written to the log file and PCRAMMET stops. If the necessary
meteorological variables are present, the SAMSON data are checked
for missing data as each record is processed. If a missing value
is encountered, a message is written to the log file indicating
which variable and the date and time of occurrence.
There are no data quality checks on the mixing height data.
If a data field is blank, then the preprocessor assumes a value
of zero for the field. It is the user's responsibility to ensure
that the information in this file is complete and properly
ordered.
The structure and contents of the precipitation file do not
allow for the data to be checked for missing records - only hours
during which precipitation occurred are reported. A date and
time are passed to the routine that retrieves the hourly
precipitation. This date and time is either the values from the
CD-144 or SAMSON data file. One quality check that is performed
is to insure that special groupings of data are terminated
properly (special flags identify these groupings). Another check
on the data identifies when both liquid and solid forms of
precipitation are reported for an hour. A message indicating
such an occurrence is written to the log file, and the code used
in the data processing corresponds to liquid precipitation.
4-8
-------
4.7 DEPOSITION PARAMETER ESTIMATES
Additional meteorological parameters are required to make
estimates of dry and/or wet deposition in ISCST3. The
computation of the friction velocity and Monin-Obukhov length in
PCRAMMET is presented in this section. Stull (1988) provides a
good introduction to the theoretical basis for estimating these
parameters.
The day is divided into two regimes: stable and unstable.
The atmosphere is considered stable if the time of day is between
sunset and sunrise (of the next day) and the transfer of heat is
toward the earth's surface. The atmosphere is unstable if the
time of day is between sunrise and sunset and the transfer of
heat is away from the surface. The parameters of interest in the
deposition process are surface roughness length (z0) , the surface
friction velocity (u*) and the Monin-Obukhov length (L).
The surface roughness length has been discussed in previous
sections. The surface friction velocity is a characteristic
velocity based on (wind) shear stresses at the earth's surface.
The Monin-Obukhov length is a stability parameter that relates
this velocity to the transport of heat. In the next two
sections, the estimates of these values are discussed for the
site where the preprocessor input data were measured. In the
final section, these results then are used to estimate the
parameters at the site where the output from PCRAMMET are to be
applied.
4.7.1 Unstable Atmosphere
During daytime convective conditions (L < 0), the surface of
the earth is heated, resulting in an upward transfer of heat.
Hourly estimates of this heat flux are required to estimate u*
and L. The estimates for the heat flux here follow the
4-9
-------
development of Holtslag and van Ulden (1983). The heat flux is
estimated from cloud cover, surface temperature, Bowen ratio and
albedo, as described below.
Once the heat flux is computed, u* and L are determined
through an iterative procedure using surface layer similarity.
While u. and L change with each iteration, the hourly heat flux
remains fixed.
A simple equation that expresses the energy balance at the
earth's surface is:
RN+Qf = H + XE + G (4.1)
where RN is the net radiation, Qf is the anthropogenic heat flux,
H is the sensible heat flux, AB is the latent heat flux, and G is
the flux of heat into the ground. Each term is expressed as
W m"2. The value of G is assumed to be proportional to the left
side of Eq. 4-1, i.e., G = cg (RN + Qf) , where cg is the fraction
of the net radiation absorbed at the ground, and is specified by
the user. Using this estimate for G and the definition of the
Bowen ratio, B0 = H / AB, which was specified by the user, the
following expression for the sensible heat flux, H, is obtained
(i.o-Cg)*;
(4-2>
B
o
where RN* = RN + Qf.
The net radiation, RN, is estimated from total incoming
solar radiation, R, as
RN= (l-r)R-IN (4.3)
4-10
-------
where r is the user-specified surface albedo (dimensionless), and
IN is the net long-wave radiation at the earth's surface as given
by Holtslag and van Ulden (1983). The anthropogenic heat flux,
Qf, specified by the user is then added to the net radiation to
obtain J?w*.
In the general case in which clouds are present, R is
computed using the following formula proposed by Kasten and
Czeplak (1980)
R = R0 ( I +blNt'2) (4.4)
where R0 (W m"2) is the incoming solar radiation at ground level
for clear skies, and N is the fractional opaque cloud cover. The
empirical coefficients b1 and b2 are assigned the values of -0.75
and 3.4, respectively. If cloud cover is missing for a
particular hour, then PCRAMMET assumes complete overcast (i.e.,
10/10 cloud cover) and proceeds with the calculations. A warning
message is written to the log file to indicate such an
occurrence.
The incoming solar radiation for clear skies R0 is given by
R0 = a^incj) + a2 (4.5)
where 4> is the elevation of the sun above the horizon (degrees) ,
a; = 990 W m"2 and az = -30 W m"2. The constants a: and az account
for attenuation of the short wave radiation by water vapor and
dust in the atmosphere. The values used in PCRAMMET are
appropriate for mid-latitudes (Holtslag and van Ulden, 1983) .
Substituting Eqs. 4.4 and 4.5 into Eq. 4.3 and
parameterizing the net long-wave radiation as a function of
temperature and cloud cover, Holtslag and van Ulden (1983)
estimate the net radiation as
4-11
-------
(1 - r) R + c. T6 - o- T4 + c,N
-^ (4'6>
where OSB = 5.67 x io"8 W m"2 K"4 is the Stefan-Boltzmann constant,
and the other empirical constants are as follows:
c: = 5.31 x 10"13 W m"2 K"6,
c2 = 60 W m"2,
C3 = 0.12.
An empirical expression for the albedo as a function of
solar elevation angle is given by
r = r' + (1 - r') eav+b (4.7)
where r' is the surface albedo (dimensionless) for the sun on the
meridian specified by the user, v is the solar elevation angle in
degrees, a = -0.1, and Jb = -0.5 (1 - r')2.
PCRAMMET next computes the surface friction velocity u. and
the Monin-Obukhov length L for the unstable atmosphere through an
iterative procedure. (This technique is similar to that used in
the METPRO processor (Paine, 1987). The two equations for u* and
L used in the iteration algorithm are:
"' = z ~
1 ^ / ref \ _ IT; j. m (4.8)
o
and
p c Tu3
L = --£ 1 (4.9)
kgH
where
H is the sensible heat flux at the surface (W m"2) ,
k is the von Karman constant,
U is the wind speed (m s"1) ,
4-12
-------
zref is the anemometer height (m) ,
z0 is the surface roughness at the measurement site (m)
specified by the user,
p is the density of dry air (kg m"3) ,
cp is the specific heat capacity of air (1004 J kg"1 deg"1) ,
T is temperature (K) , and
g is the acceleration due to gravity (9.81 m s'2) .
The values for W and ₯0 (Lumley and Panofsky, 1964 and Businger,
1973) are:
£) +ln(-^H-) - 2 tan"1
(4.10)
1 +u 1 +u
= 2 In ( } + In ( -} -2 tan'1 (4.11)
2 2
where
U = ( 1 - 16z . / L )1/4 (4.12)
u = ( 1 - 16z / L )1/4 (4.13)
This procedure requires an initial guess for u., which is
found by initially setting *P and W0 to zero. The iteration
continues until consecutive values of L differ by 1% or less.
4-13
-------
4.7.2 Stable Atmosphere
The calculations of u* and L for the stable atmosphere
(L > 0) are based on an approach outlined by Venkatram (1980).
The approach does not require an iterative procedure as used for
the unstable atmosphere. Estimates of u. and 6* (a temperature
scale) are made from cloud cover, wind speed and temperature.
This, in turn, provides an estimate of the heat flux, and L is
computed directly from Eq. 4.9.
The method begins with the following estimate for 0*:
6. = 0.09 (1 - 0.5AT2) (4.14)
where N is the fraction of opaque cloud cover. The neutral drag
coefficient, CD (dimensionless) , is calculated as
The friction velocity is determined from
= CDU/2 ( l+( 1- ( 2uo / (CDU))2 (4.16)
where
(4.17)
and 3m = 4.7 is a dimensionless constant.
To obtain real-valued solutions for u», the following must
hold
4-14
-------
(4.18)
If this condition holds, then vu is computed from Eq. 4.16;
if this condition does not hold (under very stable conditions),
then the solution to the quadratic equation is imaginary, and a
slightly different approach is taken.
Equality in the above condition corresponds to a minimum
wind speed, C7cr, at which (and above) a real-valued solution to
Eq. 4.16 is
U =
cr
\
(4.19)
TC.
D
For this value, there is a corresponding friction velocity, u*cr,
such that
u = ER^L. (4.20)
2
For wind speeds less than this critical value, Eq. 4.16 no
longer yields a real-valued solution, and it is desirable to have
u, - 0 as U - 0. Therefore, for U < Ucr, u.cr is scaled by the
ratio U / Ucrl and u. is calculated as
(4.21)
For U < Ucr, van Ulden and Holtslag (1985) showed that there is a
nearly linear variation of 6* with u,. Therefore, 6* is similarly
scaled as
4-15
-------
u
e = e
* »cr
U.cr
(4.22)
With the u. from Eq. 4.16 or 4.21 and the 6* from Eq. 4.14 or
4.22, the heat flux H is computed as
H = -pcpu,6, . (4.23)
Finally, using these estimates of u. and H, L is computed from
Eq. 4.9.
In the case of strong winds, H may become unrealistically
large. Therefore, a limit of -64 W m"2 is placed on the heat
flux, which forces a limit on the product u»9*. This yields a
cubic equation in u,, which is solved to obtain a new u.. With
this new value for u. and H = -64 W m"2, L is recomputed from Eqs.
4.9 and 4.23 as:
L = T u* / (k g 60 (4.24)
If the value of the Monin-Obukhov length is less than the
minimum value specified by the user, then L is reset to this
minimum value and a new value for u* is computed.
4.7.3 Parameters at the Application Site
The discussion above focused on the estimates at the
measurement site. Typically, the measurement site is not the
location where the output meteorological data from PCRAMMET are
to be applied. Dry deposition estimates are sensitive to the
value of the friction velocity, therefore, the friction velocity
and Monin-Obukhov length estimated for the measurement site are
adjusted to represent the site where the output are to be
applied. With the surface roughness length entered by the user
for the application site and the estimates of u* and L at the
4-16
-------
measurement site, u* and L representative of the application site
are estimated and written to the output file.
Walcek et al. (1986) suggest that near the surface
uiu.i a U2U.2 (4.25)
for changes in the underlying surface roughness, where the
subscripts 1 and 2 represent the previous and current estimates.
PCRAMMET incorporates this approach to estimate u* and L at the
application site.
With the roughness length representative of surface
conditions at the application site, a new estimate for u* is
obtained through an iterative process using surface layer
similarity. The Monin-Obukhov length is obtained from
L2 = Lj (u*2/un)3 (4.26)
(on the first iteration, the subscript 1 represents the value at
the measurement site). When two consecutive estimates of u* are
within 1%, then the process stops.
4-17
-------
SECTION 5
PCRAMMET PROGRAM NOTES
PCRAMMET is suited for operation on a PC. The input files
are of reasonable size and the programs involved execute in a
moderate amount of time. In this section, a description of the
files and steps required to compile and link PCRAMMET is
presented. The section concludes with steps to retrieve the
program and hourly surface weather observations and twice-daily
mixing heights from the SCRAM BBS.
5.1 COMPILING AND LINKING PCRAMMET
There are five source code files associated with PCRAMMET:
PCRAMMET.FOR main program - setup, initialization and
input/output handling;
PCRLIB.FOR routines that are used by several of the
subprograms;
PCRDATA.FOR routines to process the raw input data;
PCRPARAM.FOR routines to compute the boundary layer and
deposition parameters;
PCRAM.INC variable declarations and common blocks that
are used in the routines in the files above.
The executable provided on the SCRAM BBS was created using
the Lahey F77L-32/EM Fortran Compiler, version 5.2. A math
coprocessor is mandatory for use of a Lahey-compiled executable.
If the source code is modified, the following commands will
compile the source code:
5-1
-------
d:\suJbdir\f77l3 pcrammet.for /b /i /I /no /nw /dlLAHEY
d:\suJbdir\f7713 pcrlib.for /b /i /I /no /nw
d:\suJbdir\f7713 pcrdata.for /b /i /I /no /nw
d:\suJbdir\f7713 pcrparam.for /b /i /I /no /nw
where d: \ suJbdir \ refers to the drive and directory where the
Lahey compiler and linker reside if the directory is not in your
path. The switches after the filename provide the following
control:
/b checks array subscripts and character substring bounds;
/i interface checking between subprograms;
/I lists line numbers in the event the executable program
terminates abnormally;
/no compiler options are not displayed when a file is
compiled;
/nw warning messages are not displayed when a file is
compiled.
The /dlLAHEY specifier is required because the source code uses
conditional compiler directives to properly access any command
line arguments that may be used to run PCRAMMET.
To create the executable, the following command is used:
d: \suJbdir\3861ink pcram, per lib, pcrdata, pcrparam
-stub runb -pack
*
The switches after the filenames have the following effect:
-stub runb binds the Lahey/Phar Lap 386 | DOS-Extender to
the (protected-mode) executable,
-pack performs data compression on the executable
file.
The next, and final, step is optional and simply disables
the 386[DOS-Extender banner that is shown whenever the executable
program is run:
CFIG386 PCRAMMET.EXE -nosignon.
The resulting executable code size is 380 Kb.
5-2
-------
If the user needs to create a version that does not rely on
a math coprocessor or needs to create an unformatted
meteorological file that is compatible with models compiled with
a Microsoft Fortran compiler, then PCRAMMET can be compiled and
linked using the batch file included with the PCRAMMET package.
The batch file invokes Microsoft Fortran compiler and linker and
creates an executable of about 175 Kb.
5.2 PCRAMMET AND SCRAM
The following steps for retrieving the program and data from
the SCRAM BBS, some of which may have already been performed by
the user, are all that are needed for minimal implementation of
PCRAMMET:
1) Many of the programs and data files on SCRAM are available
only in a compressed format, which includes PCRAMMET source
and executable code and the hourly surface data. These
files must be decompressed with PKUNZIP (version 2.04g) or
other program that recognizes this format. If the user does
not have PKUNZIP (version 2.04g), it can be downloaded from
the OAQPS TTN. PKUNZIP can be found in the <1> System
Utilities section of the Main Menu. Select
Archivers/Dearchivers and download PKUNZIP.EXE. If the user
is unfamiliar with downloading from the OAQPS TTN, the menu
item Help Downloading/Uploading may be useful from the
Systems Utility menu.
2) Download the file(s) containing the PCRAMMET code and
dearchive the file(s) by entering
at the DOS prompt. The files with the .FOR extension
contain the source code for the programs and the ones with
the .EXE extension are the executable modules for the same.
The .RME file is a file containing a very brief synopsis of
what is contained in this User's Guide.
5-3
-------
3) To download the hourly surface data file, select
Meteorological Data from the SCRAM Main menu, then select
urface Data followed by <1> Surface Meteorological Data
File Downloads. This will present a list of States for
which there are data available. Remember the File Area
Number of the State you wish to select as the States list
scrolls by. Enter the File Area Number and select the
station/year and download that file. The selected file
nnnnn-yy.ZIP (nnnnn = Station Number, yy = Year) should now
be dearchived by entering at the DOS
prompt. This will produce two files: Snnnnnyy.DAT and
Snnnnnyy.TXT. The Snnnnnyy.TXT file contains a 'before and
after1 listing of the missing meteorological parameters that
were filled in by the SCRAM staff before the files were
placed on the SCRAM BBS. The Snnnnnyy.DAT file contains the
surface meteorological data in a 28 byte format used by the
SCRAM BBS to conserve disk space. Optionally, this file may
be converted to the NWS CD-144 format by executing the
MET144 program. This is accomplished by entering and selecting the expansion
option (1) when the program begins execution. The
Snnnnnyy.EXP file will contain the surface data in CD144
format and is now ready for input into PCRAMMET. A note on
the MET144 program - the edit option (0) will function
properly only on the SCRAM 28-byte record format file. If
there is no 'I1 in the FLAG field of the station selection
menu on the SCRAM BBS, the data in the file should be
complete. If an 'I1 is present in the FLAG field, the data
are incomplete and the user may wish to consider another
meteorological data file to use for modeling.
Data for all NWS surface stations were considered for
placement on the SCRAM BBS; however, the data for many of
the sites were incomplete. Reasons for not placing the data
on the SCRAM BBS included less than 24 observations per day
5-4
-------
or several months of missing data. If an alternate station
is selected for model analysis, that station should be
representative of the site.
4) Download the twice daily mixing height data file. Select
Meteorological Data from the SCRAM Main menu, then
select Mixing Height Data followed by <2> Mixing Height
Data File Downloads. This will present a list of States for
which there are data available. Remember the File Area
Number of the State you wish to select as the list of States
scrolls by. Enter the File Area Number and select the
station/year that you wish to download. This download
process produces the file containing mixing height data
named nnnnn-yy.TXT. Again, if an 'I1 is present in the FLAG
field of the station selection menu, the user may wish to
consider another site for modeling. The step to add an
initialization record has been removed in this version of
PCRAMMET.
5-5
-------
SECTION 6
ERROR AND WARNING MESSAGES
There are several conditions under which PCRAMMET may write
warning and error messages. Warning messages are written to the
log file (PCRAM.LOG) and PCRAMMET continues processing the data.
Error conditions are fatal and a single error message is written
to the log file and PCRAMMET stops processing the data. In the
next two sections, the warning and error messages generated by
PCRAMMET, with a brief explanation of each, is presented.
6.1 WARNING MESSAGES
In the messages below, text in italics indicates that a
value (for example, the date) will appear in the actual message
rather than the italicized text.
Rural Mixing Height < 10 m ( x.x) for (yy/mm/dd/hh) date/hour
Indicates that an estimate of the rural mixing height was
less than 10 meters. The estimated height and the date of
occurrence are reported.
Urban Mixing Height < 10 m ( x.x) for (yy/mm/dd/hh) date/hour
Indicates that an estimate of the urban mixing height was
less than 10 meters. The estimated height and the date of
occurrence are reported.
6-1
-------
Warning more than one type of precipitation reported on
(YYDDDHH):(date/hour)
format TYPE = nnnnnnnn PRECIP. CODE USED = x
If more than one type of precipitation is reported, then
PCRAMMET informs the user of the date (as year and Julian
day) and hour when the multiple precipitation types
occurred, the surface data file format (CD144, SCRAM or
SAMSON), the precipitation code, and the code that was
written to the output file. The code for liquid
precipitation is written to the output file.
CCCODE: The character " " is not allowable. Cloud cover defaults
to 10.
Indicates a blank in the cloud cover field. Occurs many
times when the 28-byte record surface file is used instead
of the 80-byte record file. MET144 must be used to expand
the 28-byte record file to 80-bytes.
FILMET: TD-3240 precip substituted for SAMSON on (yy/mm/dd/hh):
date/hour
If the precipitation was missing in the data file retrieved
from the SAMSON CD-ROM and the user responded that the
SAMSON data are to be supplemented with TD-3240 data, then
PCRAMMET writes this message to the log file for the data
and time shown.
The following messages appear if the variable referenced is
missing for the date and time displayed in the message. FILCD4
refers to CD-144 format data (and the subroutine that generated
the message) and FILSAM refers to data retrieved from the SAMSON
CD-ROM (and the subroutine that generated the message).
6-2
-------
FILCD4: Wind direction missing for (yy/mm/dd/hh) date/hour
FILCD4: Wind speed missing for (yy/mm/dd/hh) date/hour
FILCD4: Station pressure missing for (yy/mm/dd/hh) date/hour,
using 1000 mb (Note: this message is seen only if the run is
for DRY or WET deposition)
FILCD4: Temperature missing for (yy/mm/dd/hh) date/hour
FILSAM: Wind direction missing for (yy/mm/dd/hh) date/hour
FILSAM: Wind speed missing for (yy/mm/dd/hh) date/hour
FILSAM: Station pressure missing for (yy/mm/dd/hh) date/hour,
using 1000 mb
FILSAM: Temperature missing for (yy/mm/dd/hh) date/hour
FILSAM: Cloud cover missing for (yy/mm/dd/hh) date/hour
FILSAM: Ceiling height missing for (yy/mm/dd/hh) date/hour
FILSAM: Precipitation missing for (yy/mm/dd/hh) date/hour
6.2 ERROR MESSAGES
There are about 40 error messages that could originate from
PCRAMMET. PCRAMMET stops processing data if any of the follwoing
conditions occurs. The messages are:
ERROR OPENING THE INPUT FILE
An input file could not be opened.
ERROR OPENING FILE FOR SCREEN INPUT RESPONSES
The file that will be used to capture the user responses
during an interactive prompt/response run could not be
opened.
ERROR READING THE INPUT FILE: DEPOSITION TYPE
A runtime error was encountered while reading deposition
type from the response file.
6-3
-------
INCORRECT DEPOSITION TYPE SPECIFIED:
An error was encountered while reading the response file:
the deposition type - NONE, DRY or WET - was not correctly
specified.
ERROR READING THE INPUT FILE: OUTPUT FILE TYPE
An error was encountered while reading the response file:
the output file type (ASCII or UNFORM), was not specified
properly.
ERROR READING THE INPUT FILE: SURFACE FILE NAME
An error was encountered while reading the response file:
the input hourly surface observation filename was not
specified properly.
ERROR READING THE INPUT FILE: SURFACE FILE TYPE
An error was encountered while reading the response file:
the file format type (CD144 or SAMSON), was not specified
properly.
ERROR READING THE INPUT FILE: MIXING HEIGHT FILE NAME
An error was encountered while reading the response file:
the input mixing height filename was not specified properly.
ERROR READING THE INPUT FILE: PRECIPITATION YES|NO
An error was encountered while reading the response file:the
response as to the use of precipitation data was invalid.
ERROR READING THE INPUT FILE: PRECIP FILE NAME
An error was encountered while reading the response file:
the input hourly precipitation data filename was not
specified properly.
6-4
-------
ERROR READING THE INPUT FILE: PRECIP FILE TYPE
An error was encountered while reading the response file:
the precipitation file type (FIXED or VARIABLE) was not
specified properly.
ERROR READING THE INPUT FILE: SITE LATITUDE
An error was encountered while reading the response file:
the station latitude was improperly specified - this message
is seen only if the surface observations are CD144 or SCRAM
format.
ERROR READING THE INPUT FILE: SITE LONGITUDE
An error was encountered while reading the response file:
the station longitude was improperly specified - this
message is seen only if the surface observations are CD144
or SCRAM format.
ERROR READING TIME ZONE FROM THE INPUT FILE
An error was encountered while reading the response file:
the surface station's time zone was improperly specified -
this message is seen only if the surface observations are
CD144 or SCRAM format.
ERROR OPENING THE SURFACE FILE
An error occurred when attempting to open the file of hourly
surface observations.
ERROR OPENING THE MIXING HEIGHT FILE:
An error occurred when attempting to open the file of mixing
height data.
ERROR OPENING THE PRECIPITATION FILE:
An error occurred when attempting to open the file of
precipitation data.
6-5
-------
PRECIP FILE NOT VARIABLE FORMAT AS SPECIFIED BY USER
The user specified that the precipitation data are variable-
length block data; PCRAMMET determined that the format is
not VARIABLE-length. The format is likely FIXED-length, or
a format unfamiliar to PCRAMMET.
ERROR OPENING TEMPORARY PRECIPITATION FILE
When a variable-length precipitation file is used, a
temporary file is opened to reformat the data for internal
use. The attempt to open this temporary file failed.
PRECIP FILE NOT FIXED FORMAT AS SPECIFIED BY USER
The user specified that the precipitation data are fixed-
length block data; PCRAMMET determined that the format is
not FIXED-length. The format is likely VARIABLE-length, or
a format unfamiliar to PCRAMMET.
ERROR OPENING PRECIPITATION FILE:
The precipitation file does not exist - check the spelling
or the path.
ERROR OPENING OUTPUT FILE (UNFORM):
The attempt to open the output file as an unformatted file
failed.
ERROR OPENING OUTPUT FILE (ASCII):
The attempt to open the output file as an ASCII file failed.
SURFACE FILE NOT OF TYPE CD-144 AS SPECIFIED BY USER
The user specified that the hourly surface observations are
in the CD144 format; PCRAMMET has determined that the format
is not the CD144 format. The format is likely to be SAMSON,
SCRAM, or possibly a format unfamiliar to PCRAMMET.
6-6
-------
SURFACE FILE NOT OF TYPE SAMSON AS SPECIFIED BY USER
The user specified that the hourly surface observations are
in the SAMSON format; PCRAMMET has determined that the
format is not the SAMSON format. The format is likely to be
CD144, SCRAM, or possibly a format unfamiliar to PCRAMMET.
SURFACE FILE NOT OF TYPE SCRAM AS SPECIFIED BY USER
The user specified that the hourly surface observations are
in the SCRAM format; PCRAMMET has determined that the format
is not the SCRAM format. The format is likely to be CD144,
SAMSON or possibly a format unfamiliar to PCRAMMET.
SCRAM DATA AND WET DEPOSITION NOT COMPATIBLE
The user specified SCRAM data for the hourly surface
observation file and processing for wet deposition. These
two options are not compatible - wet deposition requires
information on the precipitation type (when precipitation is
occurring) which is available from the present weather
codes. The present weather codes are not in the SCRAM
meteorological data files. The user has to choose an
alternate format for the surface observations or not process
the data for wet deposition.
ERROR READING HEADER RECORD OF THE SURFACE FILE:
An error was encountered while reading one of the header
records of a SAMSON-formatted hourly surface observation
data file.
ILLEGAL VARIABLE ID IN HEADER RECORD:
An error was encountered while decoding the second header
record (the list of weather variables in the file) of a
SAMSON-formatted hourly surface observation data file.
6-7
-------
INSUFFICIENT DATA IN SAMSON FILE FOR PROCESSING
After decoding the second header record in the SAMSON data
file, there is insufficient data to estimate the parameters
for any dispersion model.
INSUFFICIENT DATA IN SAMSON FILE FOR WET DEPOSITION
After decoding the second header record in the SAMSON data
file, there is insufficient data to estimate the parameters
for wet deposition (precipitation type and amount).
ERROR READING SAMSON SURFACE DATA:
An error was encountered while reading the hourly surface
data from a SAMSON-formatted data file.
ERROR READING CD144 SURFACE DATA:
An error was encountered while reading the hourly surface
data from a CD144-formatted data file.
ERROR READING MIXING HEIGHT DATA:
An error was encountered while reading the twice-daily
mixing height data.
SURFACE AND MIXING HEIGHT TIME STAMP MISMATCH:
The date of the hourly surface observations and mixing
height data are not synchronized.
SURFACE AND PRECIP DATA TIME STAMP MISMATCH:
The date of the hourly surface observations and
precipitation data are not synchronized.
STABILITY CALCULATED TO BE LESS THAN 1:
The estimate of the Pasquill-Gifford stability category is
in error.
6-8
-------
ANEMOMETER HT < ROUGHNESS LENGTH
The anemometer height specified in the response file (batch
processing) is less than the surface roughness length. This
message will appear if either the roughness length at the
measurement site or application site is above the anemometer
height.
ANEMOMETER HT < 0.0
The anemometer height specified in the response file (batch
processing) is less than 0.0.
ALBEDO OUT OF RANGE
The albedo specified in the response file (batch processing)
is either less than 0.0 or greater than 1.0.
NET RADIATION ABSORBED BY GROUND OUT OF RANGE
The fraction of the net radiation absorbed by the ground
specified in the response file (batch processing) is less
than 0.0 or greater than 1.0.
These last four messages only appear when using PCRAMMET in
a batch mode. In the interactive mode, PCRAMMET prompts the user
for another value. In the batch mode, PCRAMMET cannot prompt for
another value, so an error message is written to the log file and
the preprocessor stops.
6-9
-------
SECTION 7
REFERENCES
Businger, J. A., 1973: Turbulent Transfer in the Atmospheric
Surface Layer. Workshop on Micrometeorology, D. Haugen
(editor). American Meteorological Society, Boston, MA
02108.
Hanna, S.R. and J.C. Chang, 1991: Modification of the Hybrid
Plume Dispersion Model (HPDM) for Urban Conditions and Its
Evaluation Using the Indianapolis Data Set. Vol. I. User's
Guide for HPDM-Urban. Sigma Research Corporation, Concord,
MA, 01742.
Holtslag, A. A. M. and A. P. van Ulden, 1983: "A Simple Scheme
for Daytime Estimates of the Surface Fluxes from Routine
Weather Data." J. Climate Appl. Meteorology, 22.'- 517-529.
Holzworth, G.C., 1972: Mixing Heights, Wind Speeds, and Potential
for Urban Air Pollution Throughout the Contiguous United
States, Environmental Protection Agency, Publication No. AP-
101, Division of Meteorology, Research Triangle Park, NC
27711.
Iqbal, M. 1983: An Introduction to Solar Radiation,. Academic
Press, New York, NY.
Kasten, F. and G. Czeplak, 1980: "Solar and Terrestrial Radiation
Dependent on the Amount and Type of Cloud." Solar Energy,
21: 177-189.
Lumley, J. L. and H. A. Panofsky, 1964: The Structure of
Atmospheric Turbulence. Monographs and Texts in Physics and
Astronomy, Vol XII. Interscience Publ., John Wiley & Sons,
New York, NY.
NCDC, 1990: Hourly Precipitation Data TD-3240, National Climatic
Data Center, Asheville, NC 28801.
NOAA, 1970: Card Deck 144 WBAN Hourly Surface Observations
Reference Manual, available from the National Climatic Data
Center, Asheville, NC 28801.
7-1
-------
Oke, T.R., 1978: Boundary Layer Climates,. John Wiley & Sons,
New York, NY.
Oke, T.R., 1982: "The Energetic Basis of the Urban Heat Island."
Quart. J. Royal Meteor. Soc., 108; 1-24.
Paine, R.J., 1987: User's Guide to the CTDM Meteorological
Preprocessor fMETPRO) Programf U.S. Environmental Protection
Agency, Research Triangle Park, NC 27711.
Pasquill, F.,1974: Atmospheric Diffusion, D. Van Nostrand
Company, Ltd., London, 2nd Edition.
Sellers, W.D., 1965: Physical Climatology, U. of Chicago Press.
Sheih, C.M., M.L. Wesley, and B.B. Hicks 1979: "Estimated Dry
Deposition Velocities of Sulfur Over the Eastern U.S. and
Surrounding Regions." Atmos. Environ., 13; 361-368.
Stull, R.B., 1988: An Introduction to Boundary Layer Meteorology,.
Kluwer Academic Publishers, Dordrecht, The Netherlands.
Turner, D.B., 1964: "A Diffusion Model for an Urban Area." -L.
Applied Meteorology, 3_: 83-91.
van Ulden, A. P., and A. A. M. Holtslag, 1985: "Estimation of
Atmospheric Boundary Layer Parameters for Diffusion
Applications." J. Climate Appl. Meteorology, 24: 1196-1207.
Venkatram, A., 1980: "Estimating the Monin-Obukhov Length in the
Stable Boundary Layer for Dispersion Calculations."
Boundary Layer Meteorology, 19: 481-485.
Walcek, C. J., R. A. Brost, J. S. Chang and M. L. Wesley, 1986:
"SO2, Sulfate and HNO3 Deposition Velocities Computed Using
Regional Land Use and Meteorological Data." Atmos.
Environ., 20, 949-964.
7-2
-------
APPENDIX A
FILE FORMATS
MIXING HEIGHT DATA RECORDS (SCRAN BBS/PCRAMMET FORMAT)
Element.
Mixing Station Number
Year
Month
Day
AM Mixing Value
PM Mixing Value
Columns
1- 5
6- 7
8- 9
10-11
14-17
32-35
Note: NWS format has the PM Mixing Value in positions 25-28
SURFACE DATA RECORD (28 BYTE RECORD - MET144 FORMAT)
Element Columns
Surface Station Number 1- 5
Year 6- 7
Month 8-9
Day 10-11
Hour 12-13
Ceiling Height (Hundreds of Feet) 14-16
Wind Direction (Tens of Degrees) 17-18
Wind Speed (Knots) 19-21
Dry Bulb Temperature (° Fahrenheit) 22-24
Total Cloud Cover 25-26
Opaque Cloud Cover 27-28
SURFACE DATA RECORD (80 BYTE RECORD - CD144 FORMAT)
Element Columns
Surface Station Number 1- 5
Year 6- 7
Month 8-9
Day 10-11
Hour 12-13
Ceiling Height (Hundreds of Feet) 14-16
Wind Direction (Tens of Degrees) 39-40
Wind Speed (Knots) 41-42
Dry Bulb Temperature (° Fahrenheit) 47-49
Opaque Cloud Cover 79
A-l
-------
SURFACE DATA RECORD - SAMSON FORMAT
The first record in the file retrieved from the SAMSON CD-
ROMs contains station data. The format of this record is:
Columns
001
002-006
008-029
031-032
033-036
039-044
039
040-041
043-044
047-053
047
048-050
052-053
Element
Indicator
WBAN Number
City
State
Time Zone
Latitude
Longitude
056-059 Elevation
Definition
to indicate a header record
Station number identifier
City where station is located
State where station is located
The number of hours by which the local
standard time lags or leads Universal
Time.
Station latitude
N = north of eguator
Degrees
Minutes
Station longitude
W = west, E = east
Degrees
Minutes
Elevation of the station in meters above
sea level.
The FORTRAN format of this record is:
(1X,A5,1X,A22,1X,A2,1X,I3,2X/A1,I2,1X/I2,2X,A1/I3,1X,I2/2X,I4)
Each variable is represented by a position number. This
position number always corresponds to that variable, no matter
how many or how few variables are retrieved. The second record
contains the list of variables (by a position number) that appear
in the data file. There is no particular format; the variable
number appears above the column of data it represents with at
least one space (and usually many more) between the position
numbers.
A-2
-------
The third and subsequent records contain the weather
elements retrieved from the SAMSON CD-ROMs. The data are free
format, i.e., there is at least one space between each element in
the record. The year, month, day, hour and observation indicator
always appear on each record. These are followed by the
variables retrieved by the user. If all the variables were
retrieved, they would appear in the following order:
Position Description
Year, month, day, hour (LST), observation indicator
1 Extraterrestrial horizontal radiation
2 Extraterrestrial direct normal radiation
3 Global horizontal radiation
4 Direct normal radiation
5 Diffuse horizontal radiation
6 Total cloud cover
7 Opaque cloud cover
8 Dry bulb temperature
9 Dew point temperature
10 Relative humidity
11 Station pressure
12 Wind direction
13 Wind speed
14 Visibility
15 Ceiling height
16 Present weather
17 Precipitable water
18 Broadband aerosol optical depth
19 Snow depth
20 Days since last snowfall
21 Hourly precipitation amount and flag
The online help that accompanies the CD-ROMs contains a complete
discussion of these variables, including the units, missing value
indicators and any special considerations or comments.
A-3
-------
HOURLY PRECIPITATION - TD-3240 FORMAT
Precipitation data are reported only for those hours during
which precipitation occurred. Variable-length blocks contain a
stations's precipitation record for one day on a physical record.
The format of the precipitation data for variable-length blocks
is as follows:
Field Columns Description
001 001-003 Record type
002 004-011 Station identifier
003 012-015 Meteorological element type
004 016-017 Measurement units
005 018-021 Year
006 022-023 Month
007 024-027 Day (right justified, zero filled)
008 028-030 Number of data groups to follow
009 031-034 Hour (left justified, zero filled)
010 035-040 Value of meteorological element
Oil 041 Measurement flag #1
012 042 Quality flag #2 (not used, blank)
Data groups in the same form as fields 009-012 are repeated
as many times as necessary to contain one day of values on one
record. These data would occupy fields 013 through 108, the
maximum number of fields.
Fixed-length blocks contain a stations's precipitation
record for one hour on a physical record. The structure is
identical to the variable-length blocks, except that only one
hour of data appears on the record, i.e. fields 001 through 012.
A-4
-------
The National Climatic Data Center publication TD-3240 Hourly
Precipitation (NCDC, 1990) contains a complete discussion of the
format, definitions and remarks for each of the fields presented
above.
A-5
-------
OUTPUT FILE (UNFORMATTED!
HEADER RECORD
Data type
Integer
Integer
Integer
Integer
Number Description
1 Surface Station Number
1 Surface Station Year
1 Mixing Height Station Number
1 Mixing Height Station Year
DATA RECORDS TONE PER DAY)
Data type
Integer
Integer
Real
Integer
Real
Real
Real
Real
Real
Number Description
1 Year
1 Month
1 Julian Day
24 Hourly Values of Stability Class
24 Hourly Values of Wind Speed (m/s)
24 Hourly Values of Temperature (K)
24 Hourly Values of Flow Vector
Values (degrees)
24 Hourly Values of Randomized Flow
Vector Values (degrees)
48 Array dimensioned 2,24 containing:
24 rural mixing height values (1), and
24 urban mixing height values (2) (m)
A-6
-------
OUTPUT FILE (ASCII FORMAT)
HEADER RECORD
The first record of the ASCII output file consists of the
following four variables:
Field Description
001 Surface Station Number
002 Surface Station Year
003 Mixing Height Station Number
004 Mixing Height Station Year
These variables are written with the format:
( 4(16, IX) )
DATA RECORDS (ONE PER HOUR)
If the user selected the option to process the input data
for CONCENTRATION estimates (i.e., NO DEPOSITION), then the ASCII
output file consists of the following variables, one record for
each hour of the period.
Field Description
001 Year (2 digits)
002 Month
003 Day
004 Hour
005 Random flow vector
006 Wind speed (m/s)
007 Ambient temperature (K)
008 Stability category
009 Rural mixing height (m)
010 Urban mixing height (m)
These variables are written with the format:
( 412, 2F9.4, F6.1, 12, 2F7.1 )
A-7
-------
If the user selected the option to process the input data
for DRY DEPOSITION estimates, then the following three variables
are added to the 10 above:
Field Description
Oil Friction velocity at the application site (m/s)
012 Monin-Obukhov length at the application site (m)
013 Roughness length at the application site (m)
The 13 variables are written with the format:
( 412, 2F9.4, F6.1, 12, 2F7.1, F9.4, F10.1, F8.4 )
If the user selected the option to process the input data
for WET DEPOSITION estimates, then the following three variables
are added to the 13 above:
Field Description
014 Precipitation code (1-18: liquid, 19 and above:
frozen)
015 Precipitation amount (mm)
The 15 variables are written with the format:
( 412, 2F9.4, F6.1, 12, 2F7.1, F9.4, F10.1, F8.4, 14, F7.2)
A-8
-------
APPENDIX B
TABLES OF SITE PROPERTIES
In this appendix, guidance on specifying the site properties
required for estimating the dispersion parameters is given.
Table B-l gives representative values for the surface roughness
length, B-2 for albedo, B-3 for Bowen ratio and B-4 for
anthropogenic heat flux.
TABLE B-l
Surface Roughness Length, in Meters, for Land-Use Types and
Seasons (from Sheih et al., 1979)
1.
2.
3.
4.
5.
6.
7.
8.
Land-Use Type
Water Surface
Deciduous Forest
Coniferous Forest
Swamp
Cultivated Land
Grassland
Urban
Desert Shrubland
Spring
0.0001
1.00
1.30
0.20
0.03
0.05
1.00
0.30
Summer
0.0001
1.30
1.30
0.20
0.20
0.10
1.00
0.30
Autumn
0.0001
0.80
1.30
0.20
0.05
0.01
1.00
0.30
Winter
0.0001
0.50
1.30
0.05
0.01
0.001
1.00
0.15
B-l
-------
TABLE B-2
Albedo1 of Natural Ground Covers for Land-Use Types and
Seasons (from Iqbal, 1983)
1.
2.
3.
4.
5.
6.
7.
8.
Land-Use Type
Water Surface
Deciduous Forest
Coniferous Forest
Swamp
Cultivated Land
Grassland
Urban
Desert Shrubland
Spring
0.12
0.12
0.12
0.12
0.14
0.18
0.14
0.30
Summer
0.10
0.12
0.12
0.14
0.20
0.18
0.16
0.28
Autumn
0.14
0.12
0.12
0.16
0.18
0.20
0.18
0.28
Winter2
0.20
0.50
0.35
0.30
0.60
0.60
0.35
0.45
See also Iqbal (1983) for specific crops or ground
covers.
Definitions of Seasons:
Spring: Periods when vegetation is emerging or partially
green. This is a transitional situation that
applies for 1-2 months after the last killing frost
in spring.
Summer: Periods when vegetation is lush and healthy,
typical of mid-summer, but also of other seasons
where frost is less common.
Autumn: Periods when freezing conditions are common,
deciduous trees are leafless, crops are not yet
planted or are already harvested (bare soil
exposed), grass surfaces are brown, and no snow is
present.
Winter: Periods when surfaces were covered by snow, and
when temperatures are sub-freezing.
Winter albedo depends upon whether a snow cover is
present continuously, intermittently, or seldom. Albedo
ranges from about 0.30 for bare snow cover to about 0.65
for continuous cover.
B-2
-------
TABLE B-3a
Daytime Bowen Ratio by Land Use and Season
Dry Conditions (from Paine, 1987)
Land-Use
Water (fresh and sea)
Deciduous Forest
Coniferous Forest
Swamp
Cultivated Land
Grassland
Urban
Desert Shrubland
Spring
0.1
1.5
1.5
0.2
1.0
1.0
2.0
5.0
TABLE
Daytime Bowen Ratio by
Average
Land-Use
Water (fresh and sea)
Deciduous Forest
Coniferous Forest
Swamp
Cultivated Land
Grassland
Urban
Desert Shrubland
Conditions
Spring
0.1
0.7
0.7
0.1
0.3
0.4
1.0
3.0
Summer
0.1
0.6
0.6
0.2
1.5
2.0
4.0
6.0
B-3b
Land-Use and
(from Paine,
Summer
0.1
0.3
0.3
0.1
0.5
0.8
2.0
4.0
Autumn
0.1
2.0
1.5
0.2
2.0
2.0
4.0
10.0
Season -
1987)
Autumn
0.1
1.0
0.8
0.1
0.7
1.0
2.0
6.0
Winter1
2.02
2.0
2.0
2.0
2.0
2.0
2.0
10.0
Winter
1.5
1.5
1.5
1.5
1.5
1.5
1.5
6.0
B-3
-------
TABLE B-3C
Daytime Bowen Ratio by Land-Use and Season -
Wet Conditions (from Paine, 1987)
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 1.0 1.0 0.5
Desert Shrubland 1.0 5.0 2.0 2.0
B-4
-------
TABLE B-4
Average Anthropogenic Heat Flux (Qf) and Net Radiation (Q*)
for Several Urban Areas (from Oke, 1978)
Urban area/
latitude/period
Manhattan (40°N)
annual
s miner
winter
Montreal (45°N)
annual
sunner
winter
Budapest (47°N)
annual
sunner
winter
Sheffield (53°N)
annual
West Berlin (52°N)
annua I
Vancouver (49°N)
annual
summer
winter
Hong Kong (22°N)
annua I
Singapore (1°N)
annua I
Los Angeles (34°N)
annua I
Fairbanks (64°N)
annua I
Population
(x 106)
1.7
1.1
1.3
0.5
2.3
0.6
3.9
2.1
7.0
0.03
Population
density
(persons/km2)
28,810
14,102
11,500
10,420
9,830
5,360
3,730
3,700
2,000
810
Per capita
energy usage
(MJxIoVyr)
128
221
118
58
67
112
34
25
331
740
(W/m2)
117
40
198
99
57
153
43
32
51
19
21
19
15
23
4
3
21
19
0.
(W/m2)
93
52
92
13
46
100
-8
56
57
57
107
6
-110
'110
108
18
B-5
-------
TECHNICAL REPORT DATA
(Please read Instructions on reverse before completing)
1. REPORT NO. 2.
EPA-454/B-96-001
4. TITLE AND SUBTITLE
PCRAMMET User's Guide
7. AUTHOR(S)
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Pacific Environmental Services, Inc.
5001 South Miami Boulevard
P.O. Box 12077
Research Triangle Park, NC 27709-2077
12. SPONSORING AGENCY NAME AND ADDRESS
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Emissions, Monitoring, and Analysis Division
Research Triangle Park, NC 27711
3. RECIPIENT'S ACCESSION NO.
5. REPORT DATE
October 1996
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
10. PROGRAM ELEMENT NO.
1 1 . CONTRACT/GRANT NO.
68D30032
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
This document presents user instructions on the use of the PCRAMMET meteorological preprocessor
program. PCRAMMET is a PC-driven, user interactive program which merges surface and mixing height
data into a single output file for use in refined atmospheric dispersion models, such as ISC. This revision
of the PCRAMMET program allows the user to enter options needed for use in dry and wet deposition of
the ISCST3 model. PCRAMMET allows for surface meteorological data to be in any of the following
formats: (1) SCRAM BBS, (2) SAMSON CD, or (3) CD144. The mixing height data may be in the
following formats: (1) SCRAM BBS, or (2) TD9689. A precipitation file may also be used by
PCRAMMET, in the TD3240 format.
17 . KEY WORDS AND DOCUMENT ANALYSIS
a. DESCRIPTORS
Air Pollution Meteorology
Air Dispersion Models
Meteorological Processor
18. DISTRIBUTION STATEMENT
Release Unlimited
b. IDENTIFIERS/OPEN ENDED TERMS
Refined Modeling
Deposition
Dispersion
19. SECURITY CLASS (Rq>on)
Unclassified
20. SECURITY CLASS (Page)
Unclassified
c. COSATI Field/Group
21. NO. OF PAGES
98
22. PRICE
,PA Form 2220-1 (Rev. 4-77) PREVIOUS EDITION IS OBSOLETE
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