EPA
United States
Environmental Protection
Agency
EPA-600/8-91-032
April 1991
Research and
Development
MOBILE4
SENSITIVITY
ANALYSIS
Prepared for
Office of Air Quality Planning and Standards
Prepared by
Air and Energy Engineering Research
Laboratory
Research Triangle Park NC 27711
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EPA-600/8-91-032
April 1991
MOBILE4 SENSITIVITY ANALYSIS
FINAL REPORT
by
Mark G. Smith
Terry T. Wilson
Alliance Technologies Corporation
100 Europa Drive, Suite 150
Chapel Hill, North Carolina 27514
EPA Contract No. 68-D9-0173
Work Assignments No. 0/109 and 1/106
Project Officer: Carl T. Ripberger
Air and Energy Engineering Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
Prepared for:
U.S. Environmental Protection Agency
Office of Research and Development
Washington, DC 20460
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ABSTRACT
The purpose of this analysis is to identify the MOBILE4 input variables that can have significant
impacts on highway vehicle emissions inventories and to develop priorities for the development of
improved guidance for specifying MOBILE4 inputs. Two major factors are considered: (1) the
likelihood and potential range of variability in values for each MOBILE4 input; and (2) the potential
magnitude of the effect of these variations, in terms of impact on typical mobile source inventories.
This analysis updates previous work based on MOBILES by using MOBILE4 for the sensitivity
analysis and by adding new MOBILE4 variables. The approach used in previous work is modified
to address the specific concerns of this project (the State implementation plan [SIP] and National
Emissions Data System [NEDS] inventory/guidance context). An additional level of detail is
included for two critical variables (speed and temperature), and sensitivity to basic vehicle
inspection/maintenance program specifications (waiver and compliance rate) is also considered.
The primary sensitivity analysis is structured around two base cases representing ozone and
carbon monoxide season conditions. Ranges around the base cases are usually specified, but in
some instances, other types of alternate values are specified. In general, the base cases and
primary ranges were chosen to parallel the previous sensitivity analysis and to relate to specific
cities or national averages available from the EPA Office of Mobile Sources. The pollutants,
regions and calendar years were chosen to cover the areas, periods and pollutants of interest in
SIP inventories and other typical inventory applications. The sections of the report describe: (1)
MOBILE4 input variable values for the ozone and CO base cases; (2) the variables and ranges or
alternate values applied in the sensitivity analysis; (3) the results of the sensitivity analysis, and (4)
conclusions.
ACKNOWLEDGEMENTS
This report was furnished to the U.S. Environmental Protection Agency in partial fulfillment of
Contract No. 68-D9-0173, Work Assignments No. 0/109 and 1/106, by Alliance Technologies
Corporation, 100 Europa Drive, Chapel Hill, North Carolina. It has been subject to the Agency's
peer and administrative review and has been approved for publication as an EPA document.
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TABLE OF CONTENTS
Section Page
ABSTRACT P
LIST OF FIGURES iv
LIST OF TABLES iv
1. BACKGROUND 1
2. MOBILE4 INPUT VALUES FOR THE BASE CASES 3
3. MOBILE4 INPUT VALUES FOR SENSITIVITY ANALYSIS 5
4. SENSITIVITY ANALYSIS RESULTS 7
5. CONCLUSIONS 14
6. REFERENCES 15
APPENDIX A - MOBILE INPUT VALUES FOR VEHICLE FLEET CHARACTERISTICS .... A-1
APPENDIX B - RESULTS OF PRIMARY AND SECONDARY MOBILE4 SENSITIVITY
ANALYSES B-1
APPENDIX C - EXAMPLES OF SPEED VERSUS EMISSIONS GRAPHS .C-1
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LIST OF FIGURES
1. Primary MOBILE4 Sensitivity Analysis Results 10
2. Secondary MOBILE4 Sensitivity Analysis 12
B-1. MOBILE4 Sensitivity Analysis (Low Altitude for 1990) B-2
B-2. MOBILE4 Sensrtivity Analysis (Low Altitude for 2005) B-4
B-3. MOBILE4 Sensitivity Analysis (High Altitude for 1990) B-6
B-4. MOBILE4 Sensitivity Analysis (High Altitude for 2005) B-8
B-5. Secondary MOBILE4 Sensitivity Analysis B-10
C-1. Example of Speed Versus HC Emissions for MOBILE3 and MOBILE4 C-2
C-2. Example of Speed Versus NOX Emissions for MOBILES and MOBILE4 C-3
C-3. Example of Speed Versus CO Emissions for MOBILES and MOBILE4 C-4
LIST OF TABLES
1. Protocol for MOBILE4 Sensitivity Analysis 2
2. "Basic" I/M Program Characteristics 4
A-1. MOBILE Input Values for Vehicle Fleet Characteristics A-2
B-1. Worksheets for MOBILE4 Sensitivity Analysis B-12
rv
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METRIC CONVERSIONS
Readers more familiar with metric units may use the following factors to convert to that
system.
Nonmetric
°F
gm/mi
Ib
mph
psi
Times
0.556 (T - 32)
1.609
0.454
1.609
6.895
Yields Metric
°C
gm/kg
kg
km/h
kPa
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SECTION 1
BACKGROUND
The purpose of this analysis is to identify the MOBILE4 input variables that can have significant
impacts on highway vehicle emissions inventories, and to develop priorities for the development
of improved guidance for specifying MOBILE4 inputs. Two major factors are considered: (1) the
likelihood and potential range of variability in values for each MOBILE4 input; and (2) the potential
magnitude of the effect of these variations, in terms of impact on typical mobile source inventories.
Although it is not possible to derive specific numeric ranges of MOBILE4 inputs associated with
probabilities of error or mis-specification, this exercise attempts to use ranges that illustrate the
following cases: misinterpretation of guidance; use of MOBILE4 defaults where local conditions
are significantly different; and use of assumptions about local conditions which may not accurately
reflect actual conditions.
MOBILE4 has internal data validity checks which prevent input of values beyond the range of its
internal algorithms, which constitute a natural set of limits representing the logical boundaries of
conditions expected in the inventory context, and which also serve to reject gross input errors.
This protocol does not explicitly attempt to address input errors such as miscoding.
A previous sensitivity assessment for MOBILES is documented in Procedures for Emission
Inventory Preparation - Volume IV: Mobile Sources.1 The purposes of the current analysis are to
update the previous work to a MOBILE4 basis (using MOBILE4 as the basis for the sensitivity
analysis as well as adding new MOBILE4 variables to the analysis), and to modify the approach to
the extent possible to address the specific concerns of this project, which include guidance for
use of MOBILE4 in State implementation plan [SIP] inventories as well as methods and data for
national-scale inventories. An additional level of detail is included for two critical variables (speed
and temperature), and sensitivity to basic inspection/maintenance (I/M) program specifications
(waiver and compliance rate) is also considered. It should be noted that the figures presented in
the Volume IVsensitivity analysis as published in July 1989 do not match the text in that volume.
The primary sensitivity analysis presented here is structured around two base cases representing
ozone and carbon monoxide season conditions. Ranges around the base cases are usually
specified, but in some instances, other types of alternate values are specified. Table 1
summarizes the protocol for the primary sensitivity analysis, including all relevant MOBILE4 input
variables. In general, the base cases and primary ranges were chosen to be parallel to the previous
sensitivity analysis, and to relate to specific cities or national averages from available work by the
EPA Office of Mobile Sources (OMS). The pollutants, regions and calendar years were chosen to
cover the areas, periods and pollutants of interest in SIP inventories and other typical inventory
applications. Table 1 also specifies input value labels which correspond to the labels in the Figures
in Section 4. It should be noted that the "high" and "low" labels are related to the input values, and
do not necessarily correlate to higher and lower emissions. Derivation of the input values in the
protocol is discussed in Sections 2 and 3. Additional information concerning the importance of
accuracy in estimating key variables is provided by testing the effects of secondary sensitivity
ranges around the base cases as well as around the primary speed and temperature ranges
specified in the protocol.
The following sections describe: (1) MOBILE4 input variable values for the ozone and CO base
cases, (2) the variables and ranges or alternate values applied in the sensitivity analysis, (3) the
results of the sensitivity analysis, and (4) conclusions.
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TABLE 1. PROTOCOL FOR MOBILE4 SENSITIVITY ANALYSIS
Pollutant
Region
Calendar Year
Avg. Speed (mph)b
Avg. Temperature(°F)c
Hot/Cold Starts
VMT Mix and
Mileage Accumulation
Vehicle Age Distrib.
ASTM Class
Diurnal Temp.(°F)
Base RVP (psi)
In-use RVP (psi)
I/M Program'
Compliance
Waivers
Base Case 1:
Ozone Season
HC, CO, NOX
Low + high altitude
1990, 2005
19.6
78.1
20.6/27.3/20.6
MOBILE4 Default
MOBILE4 Default
C
60-84°F
10.5
9.0 in 1992
Basic I/M
95%
8%
Base Case 2:
CO Season
CO only
Low + high altitude
1990, 2005
19.6
43.2, no diurnal
20.6/27.3/20.6
MOBILE4 Default
MOBILE4 Default
E
No diumal
13.7
13.7
Basic I/M
95%
8%
Ozone Season
Ranges9
_
-
-
7.1(low)-35(high)
86.0(low) -91.7(high)d
5.0/5.0/5.0 (low) -
5.0/55.0/5.0 (high)
Fairbanks - California
Fairbanks - Phoenix
CorBc
72-90; 62-102d
10.5; 9.0d
9.0; 7.8d
90 - 100%9
0-16%9
CO Season
Ranges3
—
-
-
7.1(low)-35(high)
11.3(low) -66.1 (high)
57.0/0/57.0 (low) -
5.0/5.0/5.0 (high)
Fairbanks - California
Fairbanks - Phoenix
-
No diumal
-
-
90-100%9
0-16%9
a In addition, secondary ranges of 5 mph and 5°F around the base cases and ranges for speeds and temperatures were simulated.
bReaders more familiar with metric units may use the factors listed at the end of the front matter to convert to that system.
cThese are trip- and emission-weighted average temperatures as calculated by MOBILE4.
^Temperature, ASTM class, diurnal range and RVPs varied jointly for Muskegon and Sacramento cases (see Section 3).
e Percent of VMT accumulated by: Non-catalyst vehicles in cold start mode/Catalyst vehicles in hot-start mode/Catalyst vehicles in cold start mode
other fractions calculated by MOBILE4.
'See Table 2 for listing of I/M program characteristics used
gRanges for I/M combined into two cases: 100% compliance with 0% waivers (high); 90% compliance with 16% waivers (low).
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SECTION 2
MOBILE4 INPUT VALUES FOR THE BASE CASES
Emissions of hydrocarbons, nitrogen oxides and carbon monoxide (HC, NOX and CO) were all
analyzed for summer ozone season conditions, although CO is a relatively minor participant in
ozone photochemistry. Only CO was considered for the winter CO season base case, since the
other mobile source pollutants are not implicated in urban CO problems. Both low and high
altitude situations were included, although only a few counties in the western United States are
actually modeled as high altitude. The years 1990 and 2005 were selected as typical base and
projection years for SIP submittals, to provide some perspective on the relative importance of the
individual variables over time. Table 1 lists the input values used for the MOBILE4 ozone and CO
season base cases. The combination of tow and high altitude with 1990 and 2005 results in four
altitude/year scenarios under the ozone and CO season base cases.
The base case speed of 19.6 mph is the Federal Test Procedure (FTP) average speed,
developed as a typical urban driving cycle. For the ozone season base case, the average
temperature and diurnal temperature range are based on the typical conditions simulated in the
FTP. It should be noted that the "average" temperatures cited here and elsewhere are trip- and
emission-weighted average temperatures as calculated by MOBILE4, which are used in the
estimation of several MOBILE4 emission factors.
The 10.5 psi Reid vapor pressure (RVP) chosen for the ozone season base case for 1990 is the
"Phase I" volatility standard specified for most of the country beginning in 1989.2 For 2005, the
ozone season RVP of 9.0 psi reflects the effect of Phase II summertime RVP limits.3
For the CO base case, the 43.2°F average daily temperature and 13.7 psi RVP are national
averages for cold temperature CO exceedance situations, taken from a recent draft Office of
Mobile Sources (QMS) analysis entitled "Use of Cold Temperature CO Air Quality Analysis for
Clean Air Act Amendment Evaluation."* Diumal temperature ranges do not affect CO.
For both ozone and CO season base cases, MOBILE4 default values were used for VMT mix,
mileage accumulation and vehicle age distributions. For hot/cold start percentages, typical values
recommended in the MOBILE4 guidance were used.5
Both-base cases and all sensitivity runs tests assume the typical basic inspection and maintenance
(I/M) program specified in Table 2. Since this is intended as an example, the individual program
specifications were selected to be typical of current programs. The base case compliance and
waiver rates are values selected as typical of I/M programs nationwide. Generally, the other I/M
characteristics are known program variables and are less subject to variation and error than the
waiver and compliance rates.
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TABLE 2. "BASIC" I/M PROGRAM CHARACTERISTICS
I/M PROGRAM:
START YEAR (JANUARY 1): 1983
PRE-1981 MYR STRINGENCY RATE: 20%
MECHANIC TRAINING PROGRAM?: NO
FIRST MODEL YEAR COVERED: 1970
LAST MODEL YEAR COVERED: 2020
VEHICLE TYPES COVERED: LDGV, LDGT1, LDGT2
1981+MYR TEST TYPE: IDLE ONLY
1981+ MYR TEST CUTPOINTS: 1.2% CO, 220 PPM HC
ANTI-TAMPERING PROGRAM SELECTED: NONE
ADDITIONAL MOBILE4 I/M INPUTS:
WAIVER RATES: 8% (ALL YEARS)
COMPLIANCE RATE: 95%
INSPECTION TYPE: CENTRALIZED
INSPECTION FREQUENCY: ANNUAL
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SECTION 3
MOBILE4 INPUT VALUES FOR SENSITIVITY ANALYSIS
Table 1 lists the MOBILE4 input values for the ozone and CO season ranges used in the
primary sensitivity analysis, which are described below.
Speed
The low speed of 7.1 mph is from the New York City cycle, a testing protocol that represents
driving in highly-congested urban traffic. The high speed of 35 mph is based on the highest-
speed urban driving cycle used by OMS.
Temperature/Reid Vapor Pressure
Since temperature and RVP are interrelated, two cases based on recent OMS analyses for
Muskegon and Sacramento were used to create two logical joint scenarios for the ozone and
CO season primary sensitivity analyses. Muskegon represents a case in which the diurnal
temperature range is 18°F rather than the 24°F of the Federal Test Procedure (FTP) (with
corresponding trip- and emission-weighted MOBILE4 average temperature of 86.0°F rather
than the FTP average of 78.1°F). The RVP-related parameters for Muskegon are unchanged
from the base case (10.5 psi in 1990). Sacramento is in a different ASTM region, and has
incrementally lower RVPs (9.0 in 1990), as well as a larger diurnal range and higher trip- and
emission-weighted average temperature.
Hot/Cold Start Fractions
Variations in the hot/cold start fractions were selected to be parallel to the previous MOBILES
sensitivity analysis. For the ozone season, the set of input fractions labeled as "low-
represents low levels of both cold and hot starts (5 percent), resulting in a high level of
stabilized emissions. The set labeled "high" represents a high level of hot starts (55 percent)
and low levels of cold starts. For CO season, the "low" input set includes 57 percent cold
starts and the "high" set has a minimum level of hot and cold starts (5 percent), resulting in a
high percentage of stabilized emissions. These designations were used to be consistent
with the previous MOBILES analysis and the "high" and "low" terms do not refer to the
resulting emissions levels.
VMT Mix, Mileage Accumulation and Vehicle Age
Ranges for VMT mix, mileage accumulation and vehicle age distribution were based on input
variable sets used in the previous MOBILES analysis to represent significant variations from
the MOBILES defaults. Fairbanks, Alaska was selected for its high proportion of light duty
trucks, tow mileage accumulation, and relatively low numbers of older vehicles. The VMT mix
and mileage accumulation for California were chosen for the relatively high proportion of cars
in the California fleet and the higher levels of mileage accumulation reported. The vehicle age
distribution for Phoenix was used as an example of an area where vehicles have relatively long
lives. For the California and Phoenix cases, each of these variable sets was used individually.
The unique character of the local fleet in Fairbanks (e.g., no motorcycles) made it inadvisable
to use the default VMT mix for that case, so the local VMT mix was also used in the mileage
accumulation and vehicle age distribution runs for Fairbanks. This causes the results of the
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latter runs to be a combination of the effects of the two input sets, as discussed in the
following section.
Appendix A provides the values used for each of the VMT mix, mileage accumulation and
vehicle age distribution cases, and the relative changes from the MOBILE4 default values.
I/M Program Compliance and Waiver Rate
Sensitivity of MOBILE4 to I/M program parameters was limited to joint variation of compliance
and waiver rates from the base case (95 percent compliance, 8 percent waivers). The "low"
case used 16 percent waivers and 90 percent compliance, and the "high" case used 100
percent compliance and 0 percent waivers (an ideal program with respect to these variables).
These two variables were chosen because they each have a direct impact on the overall I/M
effectiveness, and are key program design and assessment parameters. The other local I/M
program characteristics are generally more static and less susceptible to mis-specification in
inventory work.
Secondary Sensitivity Runs for Speed and Temperature
In addition to the primary ozone and CO season ranges discussed above, which were chosen
to represent reasonable limits to the conditions that might be expected in actual inventory
applications, a second set of sensitivity runs was made to illustrate the effects of smaller
changes in speed or temperature. These secondary sensitivity runs were made to illustrate
the potential effects of inaccuracies in these two critical variables across their potential ranges.
These analyses were made by varying temperature and speed for each of the primary
sensitivity analysis cases in Table 1 by 5°F and 5 mph, respectively. In the ozone season
temperature runs, this was done by raising or lowering the appropriate minimum and maximum
temperatures, resulting in time- and emission-weighted average temperature differences
which were not exactly 5°F. Variables other than speed or temperature remained at the values
used for the base case or range in question.
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SECTION 4
SENSITIVITY ANALYSIS RESULTS
Figure 1 presents the results of the sensitivity analysis for the primary ozone and CO season
cases for 1990 at low altitude. Figure 2 presents the results of the secondary sensitivity runs
for speed and temperature, also for 1990 and low altitude. Appendix B provides additional
figures for 2005 and high altitude cases, as well as tables of the fleet composite emission
factors on which the figures are based. These results are discussed below.
Results for Low Altitude In 1990
Results for the low altitude base case in 1990 will be discussed in some depth since the low
altitude case applies to most of the United States, and the current task is directed at
implications for base year State implementation plan inventories. The following discussions
for the year 2005 and high altitude concentrate on the ways in which sensitivities for these
cases vary from the 1990/low altitude case.
Ozone Season
The first three graphs in Figure 1 show the variation of hydrocarbon (HC), CO and NOX fleet
composite emission factors from the ozone season base case inputs to the ozone season
ranges shown in Table 1. In general, these graphs indicate that speed and the combination of
RVP and temperature have the largest and most consistent effects. The dramatic results for
speed follow the basic relationships shown in the figures in Appendix C,6 which consist of
relatively low emissions at high speeds and progressive emission increases at lower speeds.
CO is the pollutant most affected by speed, followed by HC and then NOX. The joint variation
of temperature and RVP to simulate Muskegon and Sacramento resulted in very significant
increases in HC and CO for both cases, with NOX being reduced slightly. This overall effect is
due primarily to the differences in temperature, with the HC and CO results for Sacramento
being tempered by the lower RVP.
Both of the alternate ozone season hot/cold start ratios reduced emissions for all pollutants,
with the "low" input set causing reductions of over 10 percent for all pollutants and smaller
changes for the "high" set. Changes in the l/M program waiver and compliance rates have a
relatively small effect on HC emissions, a slightly larger effect on CO emissions, and no effect
on NOX emissions (typical l/M programs are not intended to reduce NOX).
The three variables associated with local vehicle fleet characteristics (VMT mix, mileage
accumulation, and vehicle age distribution) show relatively little effect on overall emissions in
1990. The major exception is the effect of the Fairbanks VMT mix on NOX emissions, which is
mainly due to an increase in heavy duty diesel VMT of 130 percent over the base case. Since
heavy duty diesels emit about ten times as much NOX per mile as the other vehicle types, this
single VMT increase has a dramatic effect on fleet composite NOX emissions. The Fairbanks
VMT mix was also used in conjunction with the Fairbanks vehicle age and mileage
accumulation cases, so the NOX results for these cases are affected in a similar manner. The
net result is that the Fairbanks mileage accumulation appears to have no effect and the
Fairbanks vehicle age distribution has about 9 percent additional effect on NOX emissions. Of
the other fleet-related variable cases, the only results over five percent are the effect of the
Fairbanks vehicle age distribution on HC and CO emissions and the effect of the California
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mileage accumulation on NOX emissions.
The effects of the fleet-related variables can vary among pollutants. For example, the
California mileage accumulation reduces HC by 3 percent, increases NOX by 8 percent, and
has no effect on CO (relative to the MOBILE4 default mileage accumulation, holding the other
fleet variables at MOBILE4 default values).
Carbon Monoxide Season
The last graph in Figure 1 shows the variation of CO fleet composite emission factors from the
CO season base case inputs to the CO season ranges shown in Table 1. For the cooler CO
season temperatures, speed remains a major variable, and the temperature and hot/cold start
ranges selected for the CO season also have dramatic effects on CO emissions. Effects are
especially pronounced for low speed (7.1 mph), low temperature (11.3°F) and the
cold-start-dominated hot/cold start mix. The I/M program ranges have slightly less effect at CO
season temperatures than they do at ozone season temperatures. The vehicle fleet-related
variables also have less effect at CO season temperatures.
Secondary Sensitivity Runs for Speed and Temperature
Figure 2 shows the results of further variation of speed and temperature around the base
case and ranges described in Table 1. Secondary ranges of five degrees Fahrenheit and five
miles per hour were used around both the ozone and CO season base cases and the cited
primary ranges. This exercise illustrates the sensitivity of MOBILE4 results to small potential
errors in these key variables. The "high," "tow" and "base" designations for the individual
results in Figure 2 refer to the protocol in Table 1. For example, the first three sets of bars in
the graph for HC illustrate the effect of raising or lowering the maximum and minimum
temperatures by 5°F from the FTP-based base case and the "tow" and "high" ranges which
represent Muskegon and Sacramento (with corresponding changes in the trip- and emission-
weighted averages).
In general, the results in Figure 2 indicate that relatively small differences in average speed
and temperature can have significant effects on the MOBILE4 composite fleet emission
factors for ozone season HC and for CO in both seasons. NOX is much less sensitive to
speed and temperature. As the examples of MOBILE4 emissions/speed functions in
Appendix C show, the effects are particularly pronounced for the tow speed case. It should
be noted that the very dramatic results of lowering the low speed range (7.1 mph) to 2.1 mph
("Low-5" on Figure 2) would not be expected to occur in most typical inventory development
situations. That is, it is not likely that an error of 5 mph would be made in this speed range. In
fact, 2.1 mph is beyond the valid range of MOBILE4 input for light duty vehicle speed, and
light duty vehicle speeds were actually set at 2.5 mph in this set of runs. Excluding this
extreme case, it is still clear that accurate specification of the average speed and temperature
for an area is essential to the accuracy of the resulting mobile source inventory. For example,
a 5 mph inaccuracy in speed in the 20 mph range can cause an 11 to 18 percent error in
ozone season HC emissions and a 20 to 29 percent error in CO emissions for ozone or CO
season conditions. Relative changes in CO with speed are essentially the same for the ozone
and CO seasons since they are based on the same MOBILE4 speed correction factors,
although the absolute emissions are different (see the last worksheet in Appendix B).
Temperature sensitivity runs show ozone season HC most highly affected, with CO somewhat
sensitive as well.
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Results for 2005 and for High Altitude
Appendix B includes graphs showing the results of applying the entire Table 1 primary
sensitivity analysis protocol for 2005 and for high altitude. The main purpose of these runs
was to identify any situations in which the basic conclusions obtained for low altitude in 1990
might change in the future or in the few areas considered high altitude for MOBILE4
modeling.
For all future year and high altitude cases, the effect of changing I/M program compliance and
waiver rates is marginally less than for tow altitude in 1990.
For 2005 at low altitude, the following ozone season parameters showed some significant
variation from the 1990 base year:
Effect of the specified RVP/temperature combinations is somewhat smaller for HC and
their slightly negative effects for NOX in the base year become slightly positive for 2005.
Effects of vehicle fleet parameters and hot/cold start ratios are marginally larger for HC
and CO, and are mixed for NOX.
Effects of the speed range become a little larger for HC and NOX, but are reduced for
CO.
For the CO season, the results of the specified variations in vehicle fleet parameters are
mixed, and results for hot/cold start mix, temperature and speed are marginally smaller than in
1990.
Going from low to high altitude for the two analysis years results in only a few noticeable
changes. The general effects of the vehicle fleet characteristics on ozone season HC and CO
at high altitude are somewhat greater for 1990 and are considerably greater in 2005. The
Fairbanks VMT mix appears to be responsible for the biggest changes, resulting in roughly
double the changes seen for HC at low altitude. Sensitivity to speed is slightly lower in 2005,
for ozone season HC and CO emissions as well as for CO emissions in the CO season.
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OZONE SEASON MOBILE4 SENSITIVITY RESULTS
1990, LOW ALTITUDE, HC
(2) J I/U Program (high)
I/U Program (tew) J 2
RVP/r«mp. (Socroirwnto)
ITVP/T»mp. (Uuikwgan)
V«hicl« A?* (Phowiii)
V«hkJ< Ag« (Foirbonkj)
(3) [
VUT ITa (CoTrfomie)
VUT Uii (Foirbank*)
(2) |
(") KS
us) KSS;
Sp««a (lo«)
t i
XXXSN 3'
?^^S 25
2
3 5
Uitoo9« Accum. (CoWorruo)
! a
;
Hot/CcW Stort (high)
Mot/C«ld Stort (lo»)
Sp»d (high)
>>^CVs>>^OOC>C^CC»v^ 93
1 1 ,
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
1990, LOW ALTITUDE, CO
(«) K
I/U Program (lev)
I/U Program (high)
3 •
p. (Soergnxnto)
RVP/T«mp. (Uuakcgon)
Vahieki Ag« (Pho»mx)
Vihicll Ag< (Fo'.rtwnk.)
0
0
VUT Ui> (Cortfomio)
VUT Ui< (Foirbank.)
ss »
1
s •
UilMgi Accum. (CaPrfomio)
Accum. (Fairbanks)
(7) H Hl>t/C«ld Stof. (high)
('•) 52 M«/Cc« Start (low)
{**>
So««(! (high)
-150 -100 -50 0 50 100
Percent Ch&ufe from the Base Scenario
150
200
Figure 1. Primary MOB1LE4 Sensitivity Analysis Results (Low AKttude-1990)
(continued)
10
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OZONE SEASON MOBILE4 SENSITIVITY RESULTS
1990, LOW ALTITUDE, NOx
(3)
w I
V«hlcl« Ag< (Folrtxmk.)
Mil»og« Accum. (Colifomlo)
Accum. (Folrtxjnk.)
VUT Ub< (Folrbonkj)
(2) |
<«) SS
(•) S
Sp««d (low)
I/U Program (high)
I/U Program (low)
(Socram«nto)
KVP/T«mp. (Muilogon)
V«hkl« Age (Phoonix)
a «
xs^^^M s»
VUT Uu> (CkjOfofnta)
^^^^^N a«
Hot/Cold Slort (high)
Hot/Cold Start (tow)
Sp.«d (high)
5SS "
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
CO SEASON MOBILE4 SENSITIVITY RESULTS
1990, LOW ALTITUDE, CO
(5) N I/M Program (high)
I/U Program (low) U 4
Vthldi Ag. (Pho«nl») I 1
V«hld« Ag« (Foirbonka) U 4
(1) I Uil«og« Accum. (California)
(2)
VUT UIx (California)
(30)
Hot/Cold Start* (low)
T*mp«roturv (low)
KSNXSXSN
Sp.td (low)
Uil«ag« Accum. (Fairbonks)
VUT Uix (Falrbanki)
Hot/Cold Start! (high)
T«mp«ratur« (high)
Sp«d (high)
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
Figure 1. Primary MOBILE4 Sensitivity Analysis Results (Low Attttude-1990) (Continued)
11
-------
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
SECONDARY TEMPERATURE AND SPEED RANGES FOR HC
Tampercture (tovt-5)
<«>
Teinptrcture (bce*«5)
Temporoture (hifn-S
^ 16
Temperature (low-5)
20
(8) fS Temperoture (bc«-5)
Spnd (high+i)
Speid (high-5) fc 7
(31) E
Speed I
(")
Speed (txjjc-i)
Spud (lo.t-5)
Sp>«d
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
SECONDARY TEMPERATURE AND SPEED RANGES FOR CO
Temperoture (hig.h+3)
(") ^
T.mperolur. (to. +5)
(9) E
T.mperotur. (bOM*5)
(2) 1
(12) §§
3 ®
Tamptrotur* (high-5)
S "
Tamptroturc (tD»-5)
g W
Tcmpcroturv (bose-5)
Speed (hifh+5)
Speed (hijh-5) fcga^ 17
(•") KS^^S1;
Sp»«C (lov-t-5)
Speed (IO.-5) g§55$5^&5SSSS:SSSS^^^SS§SS§SSS5g: "0
f
(20) ESS Sp**d t^"*5)
S=t« (9CM-3) g^g^g 29
-150 -100 -50 C 50 ICO 150
Percent Change from the Baae Scenario
200
Figure 2. Secondary MOBILE4 Sensitivity Analysis (Low Altttude-1990)
(continued)
12
-------
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
SECONDARY TEMPERATURE AND SPEED RANGES FOR NOx
(2) ! Temperclure (h^
Temperature (higr>-S) 5 5
Tempercture (lov-fS)
Tempercturt (bc»«+5)
\ 1
1
Speed (high-S}
Speed (lo»-»5)
(2)
Temperoture (tow-5)
(2)
Temperature (bOM-&
Speed (high*S)
0
Speed (lew-5)
(4) g Speed (baief 5)
Speed (beie-i) fe C
_j i__
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
CO SEASON MOBILE4 SENSITIVITY RESULTS
SECONDARY TEMPERATURE AND SPEED RANGES FOR CO
(5)
Temperature (high-5)
Temperature (tow-5)
Temperature (bo»e-5)
Temperature (high+5)
S 5
Temperature
5 ^
Temperolure (boee-fS)
5 5
(«) ^ Speed (high+S)
Speed (hijn-5) ^S 17
Speed (lo.-S) ^
(20)
Speed (bc«-5)
(Soie-5)
2B
170
-150 -100 -50 0 50 ICO 150
Percent Change from the Base Scenario
2CO
Figure 2. Secondary MOBILE4 Sensitivity Analysis (Low Altitude-1990) (Continued)
13
-------
SECTION 5
CONCLUSIONS
The following is a summary of the general conclusions that can be drawn from this analysis.
The most consistently significant variables identified in this analysis are speed and the
combination of Reid vapor pressure (RVP) and temperature (temperature alone for the CO
season). This is true for current and future years, and for high and low altitude.
The primary speed ranges used in this analysis are wide enough that they should encompass
the area-wide average speeds of all U.S. cities, but should not be taken as indicative of
potential errors in any area-wide inventory. The increasing sensitivity of emissions at lower
speeds indicates that methods of incorporating speeds in inventories should be oriented
toward better reflection of the true distribution of speeds. For example, a VMT-weighted
average speed for an area would not produce an appropriate average emission factor for the
area since the speed/emission relationship is non-linear.
The combinations of RVP and temperature used for the ozone season sensitivity ranges
represent realistic cases which both fall above the base case for the analysis. Results show
that the combination of these two variables can cause significant variations between areas
(about 20 to 30 percent difference in HC and CO). The effect of RVP is less pronounced in
future years, due to Federal RVP control mandates.
For the cold temperature CO season case, there is high sensitivity to the average temperature
in the lower part of the range tested. The effects of the hot/cold start percentage were also
high, especially for the case with over 50 percent of the VMT in cold start mode. The overall
results for the CO season point out the need for explicit consideration of speed, temperature
and vehicle starts in analyses of CO exceedance situations, and for the development of better
methods and more accurate data for these variables if possible.
Secondary sensitivity analyses around the base and primary ranges for temperature and
speed indicate that relatively small differences in these variables can have significant effects
on the MOBILE4 emission factors for ozone season HC and for CO in both seasons. Ozone
season HC shows the highest sensitivity to temperature (9 to 20 percent change in emissions
due to 5 degrees change in temperature), while a five mph variation in speed can have
significant effects on ozone season HC and on CO in both ozone and CO seasons. The
effects of speed changes are most pronounced at low speed, but a five mph difference can
cause HC to vary by 11 to 18 percent and CO to vary by 20 to 29 percent even in the 20 mph
range. These results further support the statements regarding the importance of accurate
speed information which were made above regarding the primary sensitivity analysis.
Results for vehicle fleet characteristics and VMT mix were only significant in a few of the cases
used in this analysis. The most dramatic result was a 36 percent increase in NOX due to a 130
percent increase in heavy duty diesel VMT in the VMT mix for Fairbanks. The specific fleet-
related variables were taken from a previous analysis and no independent attempts were
made to determine whether they actually represent appropriate alternative cases for the 1990
and 2005 analysis years. More detailed study of this area could provide inventory managers a
better perspective on the value of developing area-specific inputs for these variables, and on
methods for their development.
14
-------
SECTION 6
REFERENCES
1. Procedures for Emission Inventory Preparation -- Volume IV: Mobile Sources.
EPA-450/4-81-026d (revised). U.S. Environmental Protection Agency, Research
Triangle Park, NC. July 1989.
2. Volatility Regulations for Gasoline and Alcohol Blends Sold in Calendar Years 1989 and
Beyond. (Notice of Final Rulemaking). 54 FR 11868, March 22,1989.
3. Volatility Regulations for Gasoline and Alcohol Blends Sold in Calendar Years 1992 and
Beyond. (Notice of Final Rulemaking). 55 FR 23658, June 11,1990.
4. Wolcott, Mark A., and Dennis F. Kahlbaum. Use of Cold Temperature CO Air Quality
Analysis for Clean Air Act Amendment Evaluation. U.S. Environmental Protection
Agency, Office of Mobile Sources, Ann Arbor, Ml. November 9,1989.
5. User's Guide to MOBILE4. EPA-AA-TEB-89-01 (NTIS PB89-164271).
U.S. Environmental Protection Agency, Office of Mobile Sources, Ann Arbor, Ml.
1989.
6. MOBILES and MOBILE4 Speed Correction Factors for 1985 Light Duty Vehicles. EPA
Office of Mobile Sources Briefing Materials. U.S. Environmental Protection Agency,
Office of Mobile Sources, Ann Arbor, Ml. 1989.
15
-------
APPENDIX A
MOBILE INPUT VALUES FOR
VEHICLE FLEET CHARACTERISTICS
This worksheet includes:
Values used for each of the VMT mix, mileage accumulation and vehicle age
distribution cases. Marginal notes indicate cases where specific lines in the original
Sierra input data were MOBILES default values rather than location-specific values,
and cases in which MOBILE4 block data (or calculations based on MOBILE4
routines) were used.
Relative changes from the MOBILE4 default values.
A-l
-------
TABLE A-1. MOBILE INPUT VALUES FOR VEHICLE FLEET CHARACTERISTICS
* * * •
****
****
MY->
LDGV
LDGT1
LDGT2
HDGV
LDOV
LOOT
HDDV
MC
****
MY->
LOGV
LDGT1
LDGT2
HOGV
LDDV
LOOT
HDDV
MC
MOBILE4 DEFAULT DATA* * * *
VMT MIX for 1990 (DEFAULTS FROM MOBILE4)
LDGV LOGT1 LOGT2 HOGV LDDV LOOT
0.710 0.127 0.086 0.015 0.013 0.004
MILEAGE
1
0.131
0.156
0.176
0.182
0.178
0.201
0.529
0.047
VEHICLE
1
0.062
0.070
0.070
0.065
0.062
0.070
0.082
0.144
ACCUMULATION
2
0.124
0.145
0.162
0.167
0.164
0.175
0.496
0.044
3
0.117
0.136
0.149
0.154
0.152
0.154
0.456
0.041
REGISTRATION
2
0.082
0.092
0.092
0.131
0.082
0.092
0.165
0.168
3
0.079
0.088
0.088
0.113
0.079
0.088
0.135
0.135
RATES (DEFAULTS
4
0.111
0.126
0.137
0.142
0.140
0.136
0.419
0.038
5
0.105
0.118
0.126
0.130
0.130
0.121
0.385
0.035
HDDV
0.034
MC
0.010
FROM MOBILE4 BLOCK DATA)
6
0.099
0.110
0.116
0.120
0.120
0.108
0.354
0.032
DISTRIBUTION (DEFAULTS
4
0.075
0.083
0.083
0.097
0.075
0.083
0.111
0.109
5
0.071
0.077
0.077
0.084
0.071
0.077
0.091
0.088
6
0.067
0.072
0.072
0.072
0.067
0.072
0.075
0.070
7
0.093
0.103
0.107
0.110
0.111
0.097
0.326
0.029
8
0.088
0.096
0.099
0.102
0.102
0.088
0.300
0.026
FROM MOB1LE4
7
0.063
0.067
0.067
0.062
0.063
0.067
0.061
0.056
8
0.060
0.062
0.062
0.054
0.060
0.062
0.050
0.045
9
0.084
0.089
0.091
0.094
0.095
0.081
0.276
0.023
10
0.079
0.083
0.083
0.086
0.087
0.074
0.254
0.019
11
0.075
0.078
0.077
0.079
0.081
0.068
0.233
0.016
12
0.071
0.072
0.071
0.073
0.075
0.064
0.214
0.013
13
0.067
0.067
0.065
0.067
0.069
0.059
0.197
0.000
14
0.063
0.063
0.060
0.062
0.064
0.056
0.181
0.000
15
0.060
0.059
0.055
0.057
0.059
0.053
0.167
0.000
16
0.056
0.055
0.051
0.052
0.054
0.051
0.153
0.000
17
0.053
0.051
0.047
0.048
0.050
0.049
0.141
0.000
18
0.050
0.047
0.043
0.044
0.046
0.047
0.130
0.000
19
0.048
0.044
0.040
0.041
0.043
0.046
0.119
0.000
FOOT-
20 NOTE
0.045
0.041
0.036
0.037
0.040
0.045
0.110 CALC
0.000
BLOCK DATA)
9
0.056
0.057
0.057
0.046
0.056
0.057
0.041
0.036
10
0.052
0.051
0.051
0.040
0.052
0.051
0.034
0.029
11
0.048
0.047
0.047
0.034
0.048
0.047
0.028
0.023
12
0.045
0.041
0.041
0.030
0.045
0.041
0.023
0.097
13
0.041
0.036
0.036
0.026
0.041
0.036
0.019
0.000
14
0.037
0.031
0.031
0.022
0.037
0.031
0.015
0.000
15
0.033
0.026
0.026
0.019
0.033
0.026
0.013
0.000
16
0.029
0.021
0.021
0.016
0.029
0.021
0.010
0.000
17
0.026
0.016
0.016
0.014
0.026
0.016
0.009
0.000
18
0.022
0.011
0.011
0.012
0.022
0.011
0.007
0.000
19
0.018
0.007
0.007
0.010
0.018
0.007
0.006
0.000
20
0.034
0.044
0.044
0.052
0.034
0.044
0.024
0.000
NOTE: Columns for vehicle registration and mileage accumulation represent the last 20 model years (MY) beginning with the most recent year (1).
LDGV = Light duty gas vehicle LDDV = Light duty diesel vehicle CALC = Calculated from MOBILE4 equation
LDGT1 = Light duty gas truck to 6000 Ibs LOOT = Light duty diesel truck MOB3 = MOBILE3 default
LDGT2 = Light duty gas truck, 6000 to 8500 Ibs HDDV * Heavy duty diesel vehicle MOB4 = MOBILE4 default
HDGV = Heavy duty gas vehicle MC = Motorcycle
(continued)
-------
TABLE A-1. MOBILE INPUT VALUES FOR VEHICLE FLEET CHARACTERISTICS (Continued)
SIERRA DATA* *••
****VMT MIX - CALIF (H3-VMTHX.OATA FROM SIERRA)
LDGV
0.716
****HILEAGE
MY-> 1
LDGV 0.159
LOGT1 0.159
LDGT2 0.157
HDGV 0.197
LOOV 0.159
LOOT 0.159
HDDV 0.786
MC 0.058
****VHT MIX
LOGV
0.656
""MILEAGE
MY-> 1
>LDGV 0.128
COLDGT1 0.174
LOGT2 0.184
HOGV 0.200
LDDV 0.128
LOOT 0.176
HOOV 0.529
MC 0.047
****MILEAGE
MY-> 1
LDGV 0.128
LDGT1 0.156
LDGT2 0.176
HDGV 0.182
LDDV 0.128
LDDT 0.201
HDDV 0.529
MC 0.047
LDGT1
0.144
ACCUM. -
2
0.150
0.150
0.157
0.197
0.150
0.150
0.738
0.042
LDGT2
0.048
CALIF
3
0.140
0.140
0.141
0.180
0.140
0.140
0.720
0.030
HDGV
0.031
LDDV
0.021
(M3-MILAC.DAT
4
0.131
0.131
0.126
0.180
0.131
0.131
0.602
0.021
- FAIRBANKS (H4-FBNKS
LDGT1
0.148
ACCUM. -
2
0.095
0.161
0.169
0.181
0.095
0.163
0.496
0.044
ACCUM. -
2
0.095
0.145
0.162
0.167
0.095
0.175
0.496
0.044
LDGT2
0.084
HDGV
0.024
5
0.122
0.122
0.113
0.151
0.122
0.122
0.602
0.015
LDDT
0.004
HDDV
0.030
MC
0.006
FILE FROM SIERRA)
6
0.113
0.113
0.102
0.151
0.113
0.113
0.457
0.011
7
0.103
0.103
0.094
0.115
0.103
0.103
0.457
0.008
8
0.099
0.099
0.086
0.115
0.099
0.099
0.399
0.006
9
0.085
0.085
0.080
0.100
0.085
0.085
0.294
0.004
10 11 12 13 14 15
0.076 0.067 0.066 0.062 0.059 0.055
0.076 0.067 0.066 0.062 0.059 0.055
0.075 0.071 0.066 0.063 0.060 0.055
0.100 0.074 0.074 0.074 0.074 0.074
0.076 0.067 0.066 0.062 0.059 0.055
0.076 0.067 0.066 0.062 0.059 0.055
0.294 0.294 0.294 0.294 0.294 0.294
0.004 0.004 0.004 0.004 0.004 0.000
16
0.051
0.051
0.052
0.074
0.051
0.051
0.294
0.000
17
0.050
0.050
0.050
0.074
0.050
0.050
0.294
0.000
18
0.047
0.047
0.047
0.074
0.047
0.047
0.294
0.000
19
0.044
0.044
0.044
0.074
0.044
0.044
0.294
0.000
20
0.044
0.044
0.044
0.074
0.044
0.044
0.294
0.000
.DATA FROM SIERRA)
LDDV
0.005
LDDT
0.004
HDDV
0.079
MC
0.000
FAIRBANKS (M4-FBNKS.DATA FROM SIERRA)
3
0.086
0.150
0.156
0.164
0.086
0.151
0.456
0.041
4
0.081
0.139
0.144
0.148
0.081
0.140
0.419
0.038
5
0.077
0.129
0.133
0.134
0.077
0.130
0.385
0.035
FAIRBANKS (M4-FBHKS
3
0.086
0.136
0.149
0.154
0.086
0.154
0.456
0.041
4
0.081
0.126
0.137
0.142
0.081
0.136
0.419
0.038
5
0.077
0.118
0.126
0.130
0.077
0.121
0.385
0.035
6
0.074
0.119
0.123
0.121
0.074
0.120
0.354
0.032
7
0.071
0.111
0.114
0.110
0.071
0.111
0.326
0.029
8
0.070
0.103
0.105
0.100
0.070
0.103
0.300
0.026
.DATA FROM SIERRA WITH
6
0.074
0.110
0.116
0.120
0.074
0.108
0.354
0.032
7
0.071
0.103
0.107
0.110
0.071
0.097
0.326
0.029
8
0.070
0.096
0.099
0.102
0.070
0.088
0.300
0.026
9
0.068
0.095
0.097
0.090
0.068
0.095
0.276
0.023
MOBILE4
9
0.068
0.089
0.091
0.094
0.068
0.081
0.276
0.023
10 11 12 13 14 15
0.066 0.065 0.064 0.063 0.062 0.061
0.088 0.082 0.076 0.070 0.065 0.061
0.090 0.083 0.076 0.071 0.065 0.060
0.082 0.074 0.067 0.061 0.055 0.050
0.066 0.065 0.064 0.063 0.062 0.061
0.088 0.082 0.076 0.070 0.065 0.060
0.254 0.233 0.214 0.197 0.181 0.167
0.019 0.016 0.013 0.000 0.000 0.000
DEFAULTS FOR LDGT, HDGV. & LDDT) -- USED
10 11 12 13 14 15
0.066 0.065 0.064 0.063 0.062 0.061
0.083 0.078 0.072 0.067 0.063 0.059
0.083 0.077 0.071 0.065 0.060 0.055
0.086 0.079 0.073 0.067 0.062 0.057
0.066 0.065 0.064 0.063 0.062 0.061
0.074 0.068 0.064 0.059 0.056 0.053
0.254 0.233 0.214 0.197 0.181 0.167
0.019 0.016 0.013 0.000 0.000 0.000
16
0.060
0.056
0.056
0.045
0.060
0.056
0.153
0.000
17
0.060
0.052
0.051
0.041
0.060
0.052
0.141
0.000
FOR COMPARISON
16
0.060
0.055
0.051
0.052
0.060
0.051
0.153
0.000
17
0.060
0.051
0.047
0.048
0.060
0.049
0.141
0.000
18
0.059
0.048
0.047
0.037
0.059
0.048
0.130
0.000
ONLY
18
0.059
0.047
0.043
0.044
0.059
0.047
0.130
0.000
19
0.058
0.045
0.044
0.033
0.058
0.044
0.119
0.000
19
0.058
0.044
0.040
0.041
0.058
0.046
0.119
0.000
FOOT-
20 NOTE
0.058
0.042 MOB3
0.040 MOB3
0.030 MOB3
0.058
0.041 MOB3
0.110 CALC
0.000 MOB4
FOOT-
20 NOTE
0.058
0.041 MOB4
0.036 MOB4
0.037 MOB4
0.058
0.045 MOB4
0.110 CALC
0.000 MOB4
MOTE- Columns for vehicle rcgistrotion ond mileage accumulation represent the last 20 model years (MY) beginning with the most recent year (1).
LDGV = Light duty gas vehicle LDDV = Light duty dicscl vehicle CALC = Calculated from MOBILE4 equation
LDGT1 = Light duty gas truck to 6000 Ibs LDDT = Light duty dicscl truck
LDGT2 = Light duty gas truck, 6000 to 0500 Ibs HDDV = Heavy duty dicsel vehicle
HDGV = Heavy duty gas vehicle MC = Motorcycle
(continued)
HOB3 = MOBILES default
HOB4 = MOBILE4 default
-------
TABLE A-1. MOBILE INPUT VALUES FOR VEHICLE FLEET CHARACTERISTICS (Continued)
* * * * SIERRA DATA (CONTINUED)" * * *
****VEIMCLE
MY-> 1
LDGV 0.041
LDGT1 0.036
LDGT2 0.036
HDGV 0.019
LDDV 0.041
LDDT 0.036
HDDV 0.022
HC 0.144
****VEIIICLE
MY-> 1
LDGV 0.063
LDGT1 0.065
LDGT2 0.074
HDGV 0.049
LDDV 0.010
LDDT 0.016
HDDV 0.044
HC 0.050
****VEHICLE
HY-> 1
LDGV 0.063
LDGT1 0.065
LDGT2 0.074
HDGV 0.049
LDDV 0.063
LDDT 0.065
HDDV 0.044
HC 0.050
REGISTRATION -
2
0.100
0.089
0.089
0.058
0.100
0.089
0.047
0.168
3
0.078
0.086
0.086
0.047
0.078
0.086
0.030
0.135
REGISTRATION -
2
0.076
0.076
0.083
0.057
0.017
0.079
0.106
0.104
3
0.068
0.061
0.060
0.050
0.058
0.108
0.105
0.126
REGISTRATION -
2
0.076
0.076
0.083
0.057
0.076
0.076
0.106
0.104
3
0.068
0.061
0.060
0.050
0.068
0.061
0.105
0.126
FAIRBANKS (M4-FBNKS.DATA FROM SIERRA DATA)
4
0.075
0.068
0.068
0.057
0.075
0.068
0.044
0.109
PHOENIX
4
0.074
0.067
0.072
0.071
0.083
0.154
0.088
0.123
PHOENIX
4
0.074
0.067
0.072
0.071
0.074
0.067
0.088
0.123
5
0.075
0.064
0.064
0.075
0.075
0.064
0.069
0.008
6
0.065
0.048
0.048
0.035
0.065
0.048
0.062
0.070
(M4-PHNX.DATA
5
0.076
0.062
0.068
0.059
0.091
0.151
0.040
0.122
6
0.080
0.067
0.077
0.073
0.018
0.244
0.050
0.080
(H4-PIINX.DATA
5
0.076
0.062
0.068
0.059
0.076
0.062
0.040
0.122
6
0.080
0.067
0.077
0.073
0.080
0.067
0.050
0.080
7
0.064
0.065
0.065
0.061
0.064
0.065
0.073
0.056
8
0.071
0.070
0.070
0.069
0.071
0.070
0.080
0.045
FROM SIERRA)
7
0.079
0.068
0.081
0.072
0.199
0.134
0.052
0.073
8
0.069
0.057
0.070
0.060
0.157
0.050
0.067
0.069
9
0.067
0.073
0.073
0.049
0.067
0.073
0.059
0.036
-- USED
9
0.065
0.055
0.063
0.051
0.104
0.029
0.088
0.046
10
0.062
0.069
0.069
0.051
0.062
0.069
0.047
0.029
11
0.049
0.055
0.055
0.066
0.049
0.055
0.102
0.023
12
0.051
0.046
0.046
0.050
0.051
0.046
0.058
0.097
13 14 15 16 17 18
0.042 0.036 0.026 0.021 0.019 0.019
0.042 0.039 0.026 0.024 0.026 0.026
0.042 0.039 0.026 0.024 0.026 0.026
0.046 0.035 0.024 0.046 0.053 0.053
0.042 0.036 0.026 0.021 0.019 0.019
0.042 0.039 0.026 0.024 0.026 0.026
0.049 0.043 0.031 0.031 0.038 0.038
0.000 0.000 0.000 0.000 0.000 0.000
19
0.019
0.026
0.026
0.053
0.019
0.026
0.038
0.000
FOOT-
20 NOTE
0.019
0.026
0.026
0.053
0.019
0.026
0.038
0.000 MOB3
AS REVISED BELOW
10
0.054
0.046
0.050
0.050
0.042
0.021
0.062
0.047
11
0.047
0.042
0.043
0.053
0.013
0.001
0.044
0.039
FROM SIERRA WITH LDDV AND LDDT SET
7
0.079
0.068
0.001
0.072
0.079
0.068
0.052
0.073
8
0.069
0.057
0.070
0.060
0.069
0.057
0.067
0.069
9
0.065
0.055
0.063
0.051
0.065
0.055
0.088
0.046
10
0.054
0.046
0.050
0.050
0.054
0.046
0.062
0.047
11
0.047
0.042
0.043
0.053
0.047
0.042
0.044
0.039
12
0.045
0.043
0.043
0.050
0.012
0.001
0.022
0.030
EQUAL
12
0.045
0.043
0.043
0.050
0.045
0.043
0.022
0.030
13 14 15 16 17 18
0.041 0.032 0.025 0.019 0.017 0.014
0.042 0.036 0.031 0.023 0.023 0.022
0.039 0.032 0.025 0.019 0.018 0.017
0.050 0.042 0.037 0.025 0.028 0.022
0.008 0.005 0.003 0.003 0.002 0.001
0.001 0.001 0.002 0.001 0.001 0.000
0.025 0.040 0.041 0.037 0.021 0.015
0.022 0.015 0.011 0.010 0.007 0.004
TO LDGV AND LDGT1)
13 14 15 16 17 18
0.041 0.032 0.025 0.019 0.017 0.014
0.042 0.036 0.031 0.023 0.023 0.022
0.039 0.032 0.025 0.019 0.018 0.017
0.050 0.042 0.037 0.025 0.028 0.022
0.041 0.032 0.025 0.019 0.017 0.014
0.042 0.036 0.031 0.023 0.023 0.022
0.025 0.040 0.041 0.037 0.021 0.015
0.022 0.015 0.011 0.010 0.007 0.004
19
0.011
0.016
0.012
0.018
0.001
0.001
0.013
0.003
19
0.011
0.016
0.012
0.018
0.011
0.016
0.013
0.003
20
0.045
0.098
0.054
0.083
0.007
0.004
0.039
0.019
20
0.045
0.098
0.054
0.083
0.045
0.098
0.039
0.019
NOTE: Columns for vehicle registration and mileage accumulation represent the last 20 model years (MY) beginning with the most recent year (1).
LDGV = Light duty gas vehicle LDDV = Light duty diesel vehicle CALC = Calculated from HOBILE4 equation
LDGT1 = Light duty gas truck to 6000 Ibs LDDT = Light duty diesel truck HOB3 = HOBILE3 default
LDGT2 = Light duty gas truck, 6000 to 8500 Ibs HDDV = Heavy duty diesel vehicle HOB4 = HOBILE4 default
HDGV = Heavy duty gas vehicle HC = Motorcycle
(continued)
-------
TABLE A-1. MOBILE INPUT VALUES FOR VEHICLE FLEET CHARACTERISTICS (Continued)
PERCENT DIFFERENCE OF SIERRA DATA TO MOBILE4 DEFAULT DATA (MOBILE4 - BASE SCENARIO))*"*
(((SIERRA-MOBILE4)/MOBILE4)* 100)
****VMT MIX - CALIF
LDGV LDGT1 LOGT2 HDGV LDDV
0.8 13.4 -44.2 106.7 61.5
LOOT HDDV MC
0.0 -11.8 -40.0
*MIIEAGE ACCUM. - CALIF
MY->
LDGV
LOGT1
LDGT2
HDGV
LDDV
LDDT
HDDV
MC
1
21.4
1.9
-10.8
8.2
-10.7
-20.9
48.6
23.4
2
21.0
9.7
-3.1
18.0
-8.5
-14.3
48.8
-4.5
3
19.7
10.3
5.4
16.9
-7.9
-9.1
57.9
-26.8
4
18.0
11.1
2.9
26.8
-6.4
-3.7
43.7
-44.7
5
16.2
11.0
0.0
16.2
-6.2
0.8
56.4
-57.1
6
14.1
10.9
-2.6
25.8
-5.8
4.6
29.1
-65.6
7
10.8
9.7
-4.7
4.5
-7.2
6.2
40.2
-72.4
8
12.5
7.3
-5.1
12.7
-2.9
12.5
33.0
-76.9
9
1.2
11.2
-5.5
6.4
-10.5
4.9
6.5
-82.6
10
-3.8
2.4
-3.6
16.3
•12.6
2.7
15.7
-78.9
11
-10.7
-2.6
-2.6
-6.3
-17.3
-1.5
26.2
-75.0
12
-7.0
-6.9
0.0
1.4
-12.0
3.1
37.4
-69.2
13
-7.5
-1.5
1.5
10.4
-10.1
5.1
49.2
--
14
-6.3
-1.6
5.0
19.4
-7.8
5.4
62.4
--
15
-8.3
0.0
9.1
29.8
-6.8
3.8
76.0
--
16
-8.9
0.0
7.8
42.3
-5.6
0.0
92.2
--
17
-5.7
0.0
10.6
54.2
0.0
2.0
108.5
--
18
-6.0
6.4
16.3
68.2
2.2
0.0
126.2
--
19
-8.3
6.8
17.5
80.5
2.3
-4.3
147.1
--
20
-2.2
7.3
22.2
100.0
10.0
-2.2
167.3
--
****VHT MIX - FAIRBANKS (M4-FBNKS.DATA FROM SIERRA)
LOGV LDGT1 LDGT2 HDGV LDDV LDDT HDDV MC
-7.6 16.5 -2.3 60.0 -61.5 0.0 132.4 -100.0
****MILEAGE ACCUM. - FAIRBANKS
cn
MY-> 1
LDGV -2.3
LDGT1 11.5
LDGT2 4.5
HDGV 9.9
LDOV -28.1
LDDT -12.4
HDDV 0.0
MC 0.0
****MILEAGE
MY-> 1
LDGV -2.3
LDGT1 0.0
LDGT2 0.0
HDGV 0.0
LDDV -28.1
LDDT 0.0
HDDV 0.0
MC 0.0
2
-23.4
20.0
13.6
8.4
-42.1
-6.9
0.0
0.0
ACCUM. -
2
-23.4
0.0
0.0
0.0
-42.1
0.0
0.0
0.0
3
-26.5
18.4
13.4
6.5
-43.4
-1.9
0.0
0.0
4
-27.0
19.0
13.9
4.2
-42.1
2.9
0.0
0.0
5
-26.7
17.8
14.3
3.1
-40.8
7.4
0.0
0.0
FAIRBANKS (M4-FBNKS
3
-26.5
0.0
0.0
0.0
-43.4
0.0
0.0
0.0
4
-27.0
0.0
0.0
0.0
-42.1
0.0
0.0
0.0
5
-26.7
0.0
0.0
0.0
-40.8
0.0
0.0
0.0
6
-25.3
17.3
14.7
0.8
-38.3
11.1
0.0
0.0
7
-23.7
15.5
15.0
0.0
-36.0
14.4
0.0
0.0
8
-20.5
15.6
15.2
-2.0
-31.4
17.0
0.0
0.0
.DATA FROM SIERRA WITH
6
-25.3
0.0
0.0
0.0
-38.3
0.0
0.0
0.0
7
-23.7
0.0
0.0
0.0
-36.0
0.0
0.0
0.0
8
-20.5
0.0
0.0
0.0
-31.4
0.0
0.0
0.0
9
-19.0
15.7
15.4
-4.3
-28.4
17.3
0.0
0.0
MOBILE4
9
-19.0
0.0
0.0
0.0
-28.4
0.0
0.0
0.0
10
-16.5
14.5
16.9
-4.7
•24.1
18.9
0.0
0.0
11
-13.3
12.8
16.9
-6.3
-19.8
20.6
0.0
0.0
DEFAULTS FOR
10
-16.5
0.0
0.0
0.0
-24.1
0.0
0.0
0.0
11
-13.3
0.0
0.0
0.0
-19.8
0.0
0.0
0.0
12
-9.9
13.9
16.9
-8.2
-14.7
18.7
0.0
0.0
LDGT,
12
-9.9
0.0
0.0
0.0
-14.7
0.0
0.0
0.0
13
-6.0
13.4
16.9
-9.0
-8.7
18.6
0.0
--
HDGV. &
13
-6.0
0.0
0.0
0.0
-8.7
0.0
0.0
14
-1.6
11.1
18.3
-11.3
-3.1
16.1
0.0
--
LDDT)
14
-1.6
0.0
0.0
0.0
-3.1
0.0
0.0
15
1.7
10.2
18.2
-12.3
3.4
13.2
0.0
--
15
1.7
0.0
0.0
0.0
3.4
0.0
0.0
* "
16
7.1
10.9
17.6
-13.5
11.1
9.8
0.0
--
16
7.1
0.0
0.0
0.0
11.1
0.0
0.0
17
13.2
9.8
19.1
-14.6
20.0
6.1
0.0
--
17
13.2
0.0
0.0
0.0
20.0
0.0
0.0
18
18.0
10.6
18.6
-15.9
28.3
2.1
0.0
--
18
18.0
0.0
0.0
0.0
28.3
0.0
0.0
~ "
19
20.8
9.1
17.5
-19.5
34.9
-4.3
0.0
--
19
20.8
0.0
0.0
0.0
34.9
0.0
0.0
20
28.9
9.8
22.2
-18.9
45.0
-8.9
0.0
--
20
28.9
0.0
0.0
0.0
45.0
0.0
0.0
" "
NOTE: Columns for vehicle registration and mileage accumulation represent the last 20 model years (MY) beginning with the most recent year (1).
LOGV = Light duty gns vehicle LDDV = Light duty dicscl vehicle CAI.C = Cnlculntcd from MOHILE4 equation
LDGT1 = Light duty gas truck to 6000 Ibs LOOT = Light duty dicscl truck
LDGT2 = Light duty gas truck, 6000 to 0500 Ibs HDDV = Heavy duty diesel vehicle
IIDGV = Heavy duty gas vehicle MC = Motorcycle
MOD3 = MOI1HE3 default
MOB4 = MOBILE4 default
(continued)
-------
TABLE A-1. MOBILE INPUT VALUES FOR VEHICLE FLEET CHARACTERISTICS
(Continued)
' PERCENT DIFFERENCE OF SIERRA DATA TO MOBILE4 DEFAULTS (MOB4 - BASE SCENARIO) (CONT'Dr * * *
(((SIERRA-MOB4)/MOB4)*100)
****VEHICLE
HY->
LOGV
LDGT1
LDGT2
HDGV
LDDV
LOOT
HDDV
MC
1
-33.9
-48.6
-10.6
-70.8
-33.9
-48.6
-73.2
0.0
****VEHICLE
HY->
LDGV
LOGT1
LOGT2
HDGV
LODV
LOOT
•?" HDDV
01 HC
1
1.6
-7.1
5.7
-24.6
-83.9
-77.1
-46.3
-65.3
****VEHICUE
MY->
LDGV
LDGT1
LOGT2
HDGV
LDOV
LOOT
HDDV
MC
1
1.6
-7.1
5.7
-24.6
1.6
-7.1
-46.3
-65.3
REGISTRATION -
2
22.0
-60.9
-60.9
-55.7
22.0
-3.3
-71.5
0.0
3
-1.3
1.1
1.1
-58.4
-1.3
-2.3
-77.8
0.0
REGISTRATION -
2
-7.3
-17.4
-9.8
-56.5
-79.3
-14.1
-35.8
-38.1
3
-13.9
-30.7
-31.8
-55.8
-26.6
22.7
-22.2
-6.7
REGISTRATION -
2
-7.3
-17.4
-9.8
-56.5
-7.3
-17.4
-35.8
-38.1
3
-13.9
-30.7
-31.8
-55.8
-13.9
-30.7
-22.2
-6.7
FAIRBANKS
4
0.0
3.6
3.6
-41.2
0.0
-18.1
-60.4
0.0
PHOENIX
4
-1.3
-19.3
-13.3
-26.8
10.7
85.5
-20.7
12.8
PHOENIX
4
-1.3
-19.3
-13.3
-26.8
-1.3
-19.3
-20.7
12.0
5
5.6
-11.7
-11.7
-10.7
5.6
-16.9
-24.2
0.0
6
-3.0
-11.1
-11.1
-51.4
-3.0
-33.3
-17.3
0.0
(H4-PHNX.DATA
5
7.0
-19.5
-11.7
-29.8
28.2
96.1
-56.0
38.6
6
19.4
-6.9
6.9
1.4
-72.7
238.9
-33.3
14.3
(M4-PHNX.DATA
5
7.0
-19.5
•11.7
-29.8
7.0
-19.5
-56.0
38.6
6
19.4
-6.9
6.9
1.4
19.4
-6.9
-33.3
14.3
7
• 1.6
-28.4
-28.4
-1.6
1.6
-3.0
19.7
0.0
8
18.3
4.8
4.8
27.8
18.3
12.9
60.0
0.0
9
19.6
22.8
22.8
6.5
19.6
28.1
43.9
0.0
10
19.2
43.1
43.1
27.5
19.2
35.3
38.2
0.0
11
2.1
46.8
46.8
94.1
2.1
17.0
264.3
0.0
12
13.3
34.1
34.1
66.7
13.3
12.2
152.2
0.0
13
2.4
27.8
27.8
76.9
2.4
16.7
157.9
14 15 ,16 17 18 19
-2.7 -21.2 -27.6 -26.9 -13.6 5.6
35.5 50.0 23.8 50.0 136.4 271. A
35.5 50.0 23.8 50.0 136.4 271.4
59.1 26.3 187.5 278.6 341.7 430.0
-2.7 -21.2 -27.6 -26.9 -13.6 5.6
25.8 0.0 14.3 62.5 136.4 271.4
186.7 138.5 210.0 322.2 442.9 533.3
•"
20
-44.1
-40.9
-40.9
1.9
-44.1
-40.9
58.3
FROM SIERRA)
7
25.4
1.5
20.9
16.1
215.9
100.0
-14.8
30.4
8
15.0
-8.1
12.9
11.1
161.7
-19.4
34.0
53.3
9
16.1
-3.5
10.5
10.9
85.7
-49.1
114.6
27.8
FROM SIERRA WITH LDDV
7
25.4
1.5
20.9
16.1
25.4
1.5
-14.8
30.4
8
15.0
-8.1
12.9
11.1
15.0
-8.1
34.0
53.3
9
16.1
-3.5
10.5
10.9
16.1
-3.5
114.6
27.8
10
3.8
-9.8
-2.0
25.0
-19.2
-58.8
82.4
62.1
11
-2.1
-10.6
-8.5
55.9
-72.9
-97.9
57.1
69.6
AND LOOT SET
10
3.8
-9.8
-2.0
25.0
3.8
-9.8
82.4
62.1
11
-2.1
-10.6
-8.5
55.9
-2.1
-10.6
57.1
69.6
12
0.0
4.9
4.9
66.7
-73.3
-97.6
-4.3
-69.1
EQUAL
12
0.0
4.9
4.9
66.7
0.0
4.9
-4.3
-69.1
13
0.0
16.7
8.3
92.3
-80.5
-97.2
31.6
--
TO LDGV
13
0.0
16.7
8.3
92.3
0.0
16.7
31.6
14 15 16 17 18 19
-13.5 -24.2 -34.5 -34.6 -36.4 -38.9
16.1 19.2 9.5 43.7 100.0 128.6
3.2 -3.8 -9.5 12.5 54.5 71.4
90.9 94.7 56.3 100.0 83.3 80.0
-86.5 -90.9 -89.7 -92.3 -95.5 -94.4
-96.8 -92.3 -95.2 -93.8 -100.0 -85.7
166.7 215.4 270.0 133.3 114.3 116.7
..
AND LDGT1)
14 15 16 17 18 19
-13.5 -24.2 -34.5 -34.6 -36.4 -38.9
16.1 19.2 9.5 43.7 100.0 128.6
3.2 -3.8 -9.5 12.5 54.5 71.4
90.9 94.7 56.3 100.0 83.3 80.0
-13.5 -24.2 -34.5 -34.6 -36.4 -38.9
16.1 19.2 9.5 43.7 100.0 128.6
166.7 215.4 270.0 133.3 114.3 116.7
20
32.4
122.7
22.7
59.6
-79.4
-90.9
62.5
--
20
32.4
122.7
22.7
59.6
32.4
122.7
62.5
NOTE: Columns for vehicle registration and mileage accumulation represent the last 20 model years (MY) beginning with the most recent year (1).
LDGV = Light duty gas vehicle LDDV = Light duty diesel vehicle CALC = Calculated from MOBILE4 equation
LDGT1 = Light duty gas truck to 6000 Ibs LDDT = Light duty diesel truck
LDGT2 = Light duty gas truck, 6000 to 8500 Ibs HDDV = Heavy duty diesel vehicle
HDGV = Heavy duty gas vehicle MC = Motorcycle
MOB3 = MOBILES default
MOB4 = MOBILE4 default
-------
APPENDIX B
RESULTS OF PRIMARY AND SECONDARY
MOBILE4 SENSITIVITY ANALYSES
BAR GRAPHS
Low Altitude for 1990
Low Altitude for 2005
High Altitude forl 990
High Altitude for 2005
Secondary Sensitivity Analysis
WORKSHEETS FOR SENSITIVITY ANALYSIS
B-l
-------
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
1990, LOW ALTITUDE, HC
(2) I
I/M Program (low)
WVP/T«mp. (Sacramento)
RVP/Ump. (Uvakvaon)
V«hict« Ao« (Pbo«nu)
V«hicl. Ao. (Fairtwnka)
•Elxio* Accum. (Foirtoonk*)
VUT Ui> (Colrfornio)
W7 ui> (Folrbonkj)
(2)
(») E
(25) P?SS
Sp«>d (low)
I/U Program
I 2
25
I 2
Ullwoo* Accum. (Canfomki)
9 3
Hot/Cold Start (hlg h)
Hot/Cold Stan (low)
Sp«d (high)
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
1990, LOW ALTITUDE, CO
<«) E
I/U Program (lew)
RVP/T«mp. (Socrwrxnto)
RVP/T«mp. (Uu«k*gon)
V«JikJ. A). (Pheviix)
Vihicl* Ag< (Fortwnkj)
0
0
VUT Uh (CoMomie)
VUT U1> (Foirtxinkj)
(«) ES
(«) S^J^N1^
Sa**d (Kw)
1 1
I/U Program (high)
a *
^^ »
JS tt
1
s •
kfil*O9« Accum. (Corrfomio)
bTil*«9* Accum. (F«irt>onka)
3 s
| 2
Mot/e»:d Star, (hig-i)
Hot/Cold Stort (low)
JS>COOOvXVOO>CsXVCCC\>sXs0\> "•*'
.
-150 -100 -50 0 50 100
Percent Change from the Baae Scenario
ISO
200
Figure B-1. Primary MOBILE4 Senslttvtty Analysis Results (Low Attttude-1990)
(continued)
B-2
-------
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
1990, LOW ALTITUDE, NOx
I/U Program (h'«jh)
I/U FVogrcm (lo«)
(5) 2 "v^A«mP- (Soercmento)
(3) J RVP/T«mp. (Uu»k»oon)
(2) [ VehicW H«
V«hicl« A,, (Foirbonta)
Uil«oo« Accum. (California) g 8
^^^^^^;
VUT Ui> (Foirt»nk.)
(2) |
WT tfa (CaTrfamio)
Hot/CoW Start (hi«h)
(12) |^] Mot/Cold Start (lo.)
(6) gj SeMd (hiflh)
Speed (Ip.)
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
CO SEASON MOBILE4 SENSITIVITY RESULTS
1990, LOW ALTITUDE, CO
(5) C I/U Program (hijh)
I/U Proflrsm (low)
Vehieli *ge (Pho^nli)
Vehicle A^« (Foirbonks)
S 4
Uilecgt Accum. (Colifomio
(2) J Uileoge Accum. (Foirtmnki
VUT U;, (CoMomie) | 1
0 VWT
(JO)
Hot/Cold S-.oru (:
Het/Colc S'.cr-j (hiah)
SS2
-•CO -£0 0 £0 '.CO
Percent Change from the Base Scenario
2:0
Figure B-1. Primary MOBILE4 Sensitivity Analysis Resutts (Low AHHude-1990) (Continued)
B-3
-------
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
2005, LOW ALTITUDE, HC
I/U Program (low)
RVP/T«mp, (Socromwite)
RVP/T«mp. (Uiuktgon)
V«hld< Ag. (Falrtxmk.)
Accum. (California)
U!l*og* Accum. (Foirbonlu)
VUT Mil (California)
VUT Ui» (Fairbank»)
(5)
(2B)
Sp.id (low)
I/U Program (high)
1
28
(Phoenix)
V>hlcl« ,
s •
3 3
3 *
3 *
a •
Hot/Cold Start (high}
Hot/Cold Start (low)
Sp««d (high)
106
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
2005, LOW ALTITUDE, CO
(3) Q I/U Program (high)
I/U Program (low)
RVP/Tunp. (Saeraminto) ^^S
RVP/T«mp. (Umk.gon) 10
Vehld* Ag< (Falrbanki)
UD«ag« Aceum. (California)
VUT Uii (California)
VUT Uii (Folrbonk»)
V.hlclt Ag« (Phoonui)
s «
MlUag* Accum. (Fairbanks)
(9) g] Hot/Cold Start (high)
(16) ESS M01/00'1* slort 0")
Sp«d (high)
Sp«d (low)
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
Figure B-2. MOBILE 4 Sensitivity Analysis (Low Altitude for 2005)
(continued)
B-4
-------
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
2005, LOTT ALTITUDE, NOx
RVP/T«mp. (Socrominto)
RVP/T«mp. (Uuak»gon)
I/U Program (high)
I/U Program (low)
(2) [ V.hlcli A«. (Pho«nl>)
Ag» (Folrbonk.)
UjUogi Accum. (California)
Ull*og« Accum. (Fairbanks)
VUT Mi« (California)
VUT UU (Fairbanki)
(«)
C7) ESS
Sp..d (low)
38
NSNNN 29
3 »
31
Hot/Cold Start (high)
Hot/Cold Slort (low)
Sp..d (high)
31
-150
-100 -50 0 50 100 150
Percent Change from the Base Scenario
200
CO SEASON MOBILE4 SENSITIVITY RESULTS
2005, LOW ALTITUDE, CO
I/U Program (low)
V«hici« Ag< (FolrtMnki) ^
Uiloagi Accum. (Calilomio)
0
VUT Uii (Cofilomia)
VUT Uii (Foirbanki)
(25)
Hot/Cold StorO (low)
Tempcraturt (low)
Spetd (low)
I/U Progrom (high)
2
V«hicl« Ag> (Photnii)
6
Uileoga Accum. (Foirbonka)
Hot/Cold Slorta (hich)
Tempera tun (high)
Spcid (high)
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
Figure B-2. MOBILE 4 Sensitivity Analysis (Low Altitude for 2005) (Continued)
B-5
-------
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
1990, HIGH ALTITUDE, HC
(2) J I/U Program (high)
I/U Program (low) | 1
RVP/T«mp. (Soerarranto)
Fvp/r«np- (uwkogon) :sss^ 24
V«hleU Ag« (Phowibc)
Vohlcli Ag« (Folrbonki)
(2) J UH.oo. Aecum. (Caufomlo)
Un.ag. Aecum. (Fairbankj) (^ 7
VUT Uii (Foirbonka)
(9) CS
(22)
Sp..d (low)
VUT Uii (California)
5 4
Hot/Cold Start (high)
Hot/Cold Start (low)
Sp..d (high)
82
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
1990, HIGH ALTITUDE, CO
(3) [
I/U Program (low)
RVP/T«mp. (Sacremnito)
RVP/T«mp. (Uutkcgon)
0
V«hld« Ag« (Falrtanki)
Uil«a?« Aecum. (Folrbonki)
VUT Uii (California)
VUT Uii (Fairbanks)
(8) S
(U) KS
(^i) ^OOOC^V
Sp»d (low)
1 1
I/U Program (high)
2
5SS 21
S3 «
V.hlcl. Ag. (Pho.rUi)
S 7
UH«ag« Aecum. (CoDfomio)
3 4
2
2
Hot/Cold Start (high)
Hot/Cold Start (low)
Sp«ad (high)
^^^^c^c^^^^v^s^^^sxxsv«^^^^^ ua
! . . _ 1
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
Figure B-3. MOBILE 4 Sensitivity Analysis (High Altitude for 1990)
(continued)
B-6
-------
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
1990, HIGH ALTITUDE, NOx
(••) C
CT C
S »
(2) | Vihlck ,
V«hlcl« Ag« (Folrbanki) J
UDoagt Accum. (California)
UII*og< Accum. (Folrbonkt)
VUT Ulx (California)
VUT Ulx (Fairbanks)
Hot/Cold Start (high)
(«) SS
(7) K
Sp»d (low)
I/U Program (high)
I/M Program (low)
RVP/Ump. (Sacramento)
RVP/T«mp. (Uuik.gon)
SO
37
Hot/Cold Start (low)
Sp«.d (high)
28
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
CO SEASON MOBILE4 SENSITIVITY RESULTS
1990, HIGH ALTITUDE, CO
P) C
I/U Program (low)
V.hid. Ag« (Phoonix)
V.hicli Ag« (Fairbonki)
w C
Uil*oge Accum. (Fairbonka)
VUT Uii (California)
VUT Mix (Fairbanki)
(25) fcxxs:
Hat/Cold Start (low)
(«) ES
T«mp«ratura (low)
«« f>X^S\\\
Sp«d (low)
I/M Program (high)
2
1
3 *
UiUag* Accum. (CoDlomio)
2
1
1
Hot/Cold Start (high)
^^X^^vVO "
T«mp«raturt (high)
^^^c^^^^^c>cl s°
Sp«*d (high)
>>XVC^vVC\\\V^\VOvV>OOO U2
1 1 1
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
Figure B-3. MOBILE 4 Sensitivity Analysis (High Altitude for 1990) (Continued)
B-7
-------
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
2005, HIGH ALTITUDE, HC
I/U Program (low)
RVP/T«np. (Soerom«nlo) JSNSN 25
RVP/r«">p. (Uuak.gon) gg U
V«h!cl. Ag. (Foirbonki)
U!Uog< Accum. (Celifomio)
Ul«og« Accum. (Fairbanks)
VUT Ua (Colifomio)
VUT Uix (Foirtaonki)
V«hicli Ag< (Phcwnix)
5S "
(5)
SS
Sp««d (Ion)
I/U Program (high)
1
3 «
SS
Hot/Cold Slort (hig
Hot/Cold Stort (low)
Spud (hifh)
-ISO -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
2005, HIGH ALTITUDE, CO
4
I/U Program (low)
- (Socronwnto) ?sS3 18
KVP/T«np-
V«hlcl> Af< (Photnlx)
V*h1cl* Ag« (Folrbonki)
Ulltogi Accum. (California)
Ull«cge Accum. (Falrbonkt)
VUT Uli (C«lifomla)
VUT Uii (Foirtaonks)
(») tS
(») CSS
Spa«d (low)
I/U Program (high)
2
S3 «
3 *
a 7
S 10
Hot/Cold Slort (high)
Hoi/Cold Slort (low)
Sf».d (high)
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
Figure B-4. MOBILE 4 Sensitivity Analysis (High Altitude for 2005)
(continued)
B-8
-------
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
2005, HIGH ALTITUDE, NOx
0
0
RVP/Temp. (Sacramento)
RVP/Temp. (Uuikcgon)
V«hicU Aa« (Foirbonki)
UHaaga Accum. (California) ^ 11
LGliogo Accum. (Foirbankj) ^CvCs>i
VUT Uu (Canfomio)
VUT Ui» (Fairbanks)
(") KSS
Sp**d (low)
I/U Program (high)
I/U Program (tew)
V«hiel« Ag» (Phoinra)
32
28
Hot/Cold Slort (hljh)
Hot/Cold Start (low)
Sp»d (high)
^^^^^i 31
-150 —100 -50 0 50 100 150
Percent Change from the Base Scenario
200
CO SEASON MOBILE4 SENSITIVITY RESULTS
2005, HIGH ALTITUDE, CO
(«
I/U Program (low)
V.hlcli Ag< (Felrbonkl)
un«ag> Accum, (C«E(emla)
U1l«ao,e Accum. (Fclrbonka)
VUT UJi (Califomio)
VUT Ubi (Foirtanki)
Hot/Cold Start (low)
(»)
Sptid (low)
I/U Program (high)
2
V«hlcl« Ag« (PhoinU)
7
2
2
3 5
a •
Hot/Cold Stort (high)
T«mp«rotun (high)
Spaad (high)
59
150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
Figure B-4. MOBILE 4 Sensitivity Analysis (High Altitude for 2005) (Continued)
B-9
-------
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
SECONDARY TEMPERATURE AND SPEED RANGES FOR HC
T«npu«tun
(U)
Twnptroturi (l»43)
(«) Ei
Tcmpcratun (b«««43)
Spud (h^h-5
(») g
Sptid (boit-9)
^ «
T«mp«r«tur«
Timpcroturi (lor-S)
JO
Ttmptratur* (b«»«—5)
Spttd (h'^h+3)
7
Sp.td po.+5)
Sptid (boit-fS)
-150 -100 -50 0 50 100 150 200
Percent Change from the Base Scenario
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
SECONDARY TEMPERATURE AND SPEED RANGES FOR CO
T
-------
OZONE SEASON MOBILE4 SENSITIVITY RESULTS
SECONDARY TEMPERATURE AND SPEED RANGES FOR NOx
a)
Tamptrotura (high—5)
(2)
Temperate*™ (tew-5)
Temperature (tase-5)
Speed (hich+5)
0
(«> L
Spied (l"-5)
Ttmperotur* (lowfS)
2
(baM+5)
«) E
Speed (boie-5)
I
Speed (high-J)
Speed (lo.+S)
Speed (boe.+J)
-150 -100 -50 0 50 100 150
Percent Change from the Base Scenario
200
CO SEASON MOBILE4 SENSITIVITY RESULTS
SECONDARY TEMPERATURE AND SPEED RANGES FOR CO
(5) g
T«mperoUir» (r»fh-3)
(7) §
T.emp«rctun (lo« -3)
W E
Temperature (boee-5)
(12) g§
Speed (hi5n-i)
Speed 0°*~3)
Speed (boie-3)
I 1
Temperature (hlgM-5)
3 5
Temp«roture (lewfS)
3 7
Temperotijre (ba*e+5)
Speed (hijh+I)
Speed (lo.+5)
^55SS555S»S?SS»5SSS«S^SS5SSS?S;5SSJ 170
1 1 1
-150
-100 -SO 0 *>0 100 150
Percent Change from the Base Scenario
200
Figure B-5. Secondary MOBILE4 Sensitivity Analysis (Low Altitude-1990) (Continued)
B-ll
-------
TABLE B-1. WORKSHEETS FOR MOBILE4 SENSITIVITY ANALYSIS
PRIMARY SENSITIVITY ANALYSIS — MOBILE4 COMPOSITE
EMISSION
FACTORS (gm/mile)
LOU ALTITUDE 1990 LOU ALTITUDE 2005 HIGH ALTITUDE
ANALYSIS NON-METHANE EXHAUST EXHAUST NON-METHANE EXHAUST EXHAUST NON-METHANE EXHAUST
PARAMETERS HC CO ' NOx HC CO NOx HC CO
CO BASE CASE
05 BASE CASE
CO AVG. SPEED -LOU
CO AVG. SPEED-HIGH
03 AVG. SPEED -LOU
03 AVG. SPEED-HIGH
CO TEMPERATURE-LOU
CO TEMPERATURE-HIGH
CO HOT/COLO STARTS-LOU
CO HOT/COLD STARTS-HIGH
03 HOT/COLD STARTS-LOU
03 HOT/COLO STARTS-HIGH
03 RVP/TEMP - MUSKEGON
03 RVP/TEMP - SACRAMENTO
CO I/M PROGRAM-LOU
CO 1/M PROGRAM-HIGH
03 I/M PROGRAM-LOU
03 I/M PROGRAM- HIGH
CO VHT HIX - FBNKS
CO VMT MIX - CALIF
03 VMT MIX - FBNKS
03 VMT MIX - CALIF
CO MILEAGE ACCUH.- FBNKS
CO MILEAGE ACCUM. -CALIF
03 MILEAGE ACCUH. -FBNKS
03 MILEAGE ACCUM. -CALIF
CO VEHICLE AGE-FBNKS
CO VEHICLE AGE-PHNX
03 VEHICLE AGE-FBNKS
03 VEHICLE AGE-PHNX
2.908
2.957
5.704
2.227
2.638
2.890
3.709
3.882
3.002
2.900
2.981
2.972
3.035
2.883
3.1H
3.007
27.415
19.008
67.397
15.234
47.754
10.546
41.898
22.325
46.019
19.265
15.985
17.693
21.944
22.661
28.523
26.003
19.912
17.856
27.487
27.810
19.422
19.534
26.843
27.213
18.946
18.950
28.640
27.799
20.572
19.210
2.588
2.256
2.781
2.113
1.978
2.305
2.184
2.138
2.256
2.256
3.066
2.240
3.077
2.444
3.312
2.206
1.645
1.262
2.601
0.911
1.080
1.198
1.436
1.586
1.274
1.247
1.338
1.307
1.311
1.294
1.372
1.268
16.567
8.734
26.158
9.266
14.160
4.881
24.821
14.715
26.639
12.386
7.296
7.938
9.620
10.338
16.862
16.191
8.948
8.460
17.233
17.188
9.319
9.147
16.491
16.964
8.777
9.134
17.482
16.612
9.530
8.736
1.497
1.296
1.694
1.077
1.085
1.301
1.307
1.314
1.296
1.296
1.698
1.356
1.667
1.445
1.758
1.272
4.565
3.649
6.641
2.834
3.304
3.563
4.526
4.780
3.698
3.586
3.790
3.654
3.909
3.558
3.986
3.692
40.319
29.743
93.562
23.774
69.387
17.675
60.410
33.817
64.848
30.170
25.803
27.422
34.392
35.962
41.197
39.201
30.465
28.822
40.579
40.827
30.441
30.462
41.091
38.796
30.892
28.650
41.980
40.657
31.891
29.850
1990 HIGH ALTITUDE 2005
EXHAUST NON-METHANE EXHAUST EXHAUST
NOx HC CO NOx
2.422
2.112
2.669
1.971
1.854
2.147
2.058
2.021
2.112
2.112
2.912
2.076
2.896
2.330
3.160
2.070
2.486
1.412
2.845
1.021
1.225
1.347
1.595
1.767
1.424
1.397
1.615
1.464
1.590
1.484
1.654
1.407
18.227
10.046
28.969
10.247
16.431
5.655
29.906
16.500
28.488
13.985
8.495
9.187
11.057
11.877
18.544
17.824
10.276
9.753
19.324
19.145
11.052
10.710
18.582
18.671
10.511
10.517
19.570
18.148
11.261
9.945
1.611
1.389
1.821
1.146
1.152
1.394
1.401
1.410
1.389
1.389
1.782
1.443
1.751
1.540
1.840
1.369
(Continued)
-------
TABLE B-1. WORKSHEETS FOR MOBILE4 SENSITIVITY ANALYSIS (Continued)
PRIMARY SENSITIVITY ANALYSIS -- PERCENT CHANGE FROM BASE CASE
LOW
ANALYSIS NON-METHANE
PARAMETERS HC
CO AVG. SPEED-LOW
CO AVG. SPEED-HIGH
03 AVG. SPEED -LOU 93
03 AVG. SPEED-HIGH -25
CO TEMPERATURE-LOW
CO TEMPERATURE-HIGH
CO HOT/COLD STARTS-LOW
CO HOT/COLD STARTS-HIGH
03 HOT/COLD STARTS-LOW -11
03 HOT/COLD STARTS-HIGH -2
03 RVP/TEMP - MUSKEGON 25
03 RVP/TEMP - SACRAMENTO 31
CO I/M PROGRAM- LOW
CO I/M PROGRAM- HIGH
03 I/M PROGRAM- LOW 2
03 I/M PROGRAM-HIGH -2
CO VHT MIX - FBNKS
CO VMT MIX • CALIF
03 VHT MIX - FBNKS 1
03 VMT MIX - CALIF 1
CO MILEAGE ACCUM. -FBNKS
CO MILEAGE ACCUM. -CALIF
03 MILEAGE ACCUM. -FBNKS 3
03 MILEAGE ACCUH. -CALIF -3
CO VEHICLE AGE-F8NKS
CO VEHICLE AGE-PHNX
03 VEHICLE AGE- FBNKS 5
03 VEHICLE AGE-PHNX 2
ALTITUDE 1990 LOW
EXHAUST EXHAUST NON-METHANE
CO NOX HC
146
-44
151 23 106
-45 -6 -28
53
-19
68
-30
-16 -12 -H
-7 2 -5
15 -3 14
19 -5 26
4
-5
5 0 1
-6 0 -1
0
1
2 36 6
3-1 4
-2
-1
0 36 4
083
4
1
8 47 9
1 -2 0
ALTITUDE 2005 HIGH ALTITUDE 1990 HIGH ALTITUDE 2005
EXHAUST EXHAUST NON-METHANE
CO NOx HC
58
-44
62 31 82
-44 -17 -22
50
-11
61
-25
-16 -16 -9
-9 0 -2
10 1 24
18 1 31
2
-2
2 0 1
-3 0 -2
4
4
7 31 4
550
0
2
0 29 7
5 11 -2
6
0
9 36 9
0 -2 1
EXHAUST EXHAUST NON-METHANE
CO NOx HC
132
-41
133 26 101
-41 -7 -28
50
-16
61
-25
-13 -12 -13
-8 2 -5
16 -3 13
21 -4 25
2
-3
2 0 1
-3 0 -1
1
1
2 38 14
2-2 4
2
-4
4 37 13
-4 10 5
4
1
7 50 17
0-2 0
EXHAUST
CO
59
-44
64
-44
64
-9
56
-23
-15
-9
10
18
2
-2
2
-3
6
5
10
7
2
2
5
5
7
0
12
-1
EXHAUST
NOX
31
-17
-17
0
1
2
0
0
28
4
26
11
32
-1
(Continued)
-------
TABLE B-1. WORKSHEETS FOR MOBILE4 SENSITIVITY ANALYSIS (Continued)
w
I
SECONDARY SENSITIVITY ANALYSIS — TEMPERATURE AND SPEED RANGES
(EMISSION FACTORS [CM/MILE] and PERCENT CHANGE FROM BASE CASE)
CO TEMPERATURE
BASE
LOU
HIGH
03 TEMPERATURE
BASE
LOU
HIGH
03 TEMPERATURE
BASE
LOU
HIGH
03 TEMPERATURE
BASE
LOU
HIGH
OASE
RUN
CO
27.42
41.90
22.33
BASE
RUN
HC
2.96
3.71
3.88
BASE
RUN
CO
19.01
21.94
22.66
BASE
RUN
NOx
2.26
2.18
2.14
-5
RUN
CO
28.87
44.87
23.42
-5
RUN
HC
2.70
3.13
3.36
-5
RUN
CO
18.72
19.99
20.10
-5
RUN
NOx
2.31
2.23
2.10
+5
RUN
CO
26.29
39.12
21.24
*5
RUN
HC
3.56
4.29
4.46
+5
RUN
CO
20.82
24.27
24.56
+5
RUN
NOx
2.21
2.14
2.10
Percent
-5
CO
5
7
5
Percent
-5
HC
-9
-16
-13
Percent
-5
CO
-2
-9
-11
Percent
-5
NOx
2
2
2
Difference
+5
CO
-4
-7
-5
Difference
+5
HC
20
16
15
Difference
+5
CO
10
11
8
Difference
+5
NOx
-2
-2
-2
CO SPEED
BASE
LOU
HIGH
03 SPEED
BASE
LOU
HIGH
03 SPEED
BASE
LOU
HIGH
03 SPEED
BASE
LOU
HIGH
BASE
RUN
CO
27.42
67.40
15.23
BASE
RUN
HC
2.96
5.70
2.23
BASE
RUN
CO
19.01
47.75
10.55
BASE
RUN
NOx
2.26
2.78
2.11
-5
RUN
CO
35.11
182.16
17.89
-5
RUN
HC
3.50
13.34
2.39
-5
RUN
CO
24.56
128.97
12.39
-5
RUN
NOX
2.40
3.19
2.12
+5
RUN
CO
21.94
41.35
13.36
+5
RUN
HC
2.63
3.93
2.11
+5
RUN
CO
15.21
29.05
9.26
+5
RUN
NOx
2.17
2.50
2.14
Percent
•5
CO
28
170
17
Percent
-5
HC
18
134
7
Percent
-5
CO
29
170
17
Percent
-5
NOx
6
15
0
Difference
+5
CO
-20
-39
-12
Difference
+5
HC
-11
-31
-5
Difference
+5
CO
-20
-39
-12
Difference
+5
NOx
-4
-10
1
-------
APPENDIX C
EXAMPLES OF SPEED VERSUS EMISSIONS GRAPHS
(MOBILES AND MOBILE4 Speed Correction Factors for 1985 Light Duty Vehicles)6
C-1
-------
o
I
10
(O
c
(D
O
5?
o>
3
•o^
(D
O)
Tl
CD
n>
Q.
(D
3
C
w
I
O
m
3
55'
w
6'
a
S
O
5
m
3
a.
O
CO
o
•i—«
w
CO
5
4.5
^ 3.5-
1 3
JH
2.5
2
1.5
1
0.5
0
HC Emissions vs. Speed
Model Year 1985 LDGVs
A
A
MOBILES
i
0
i
5
10 15 20 25 30 35 40 45 50 55
Speed (miles/hour)
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
-------
n
i
w
to
c
-n
0)
O
I
ro
D)
ST
o
-*»
tn
•o
(D
M
01
z
o
M
m
3
w'
(A
5'
O
2
m
CO
0)
3
Q.
o
s
m
NOx Emissions vs. Speed
Model Year 1985 LDGVs
0)
r—I
•rH
I
a
cti
tiO
o
2-
1-
0
MOBILE4
-1
MOBILE3
0
i
10
0
15 20 25 30 35 40 45 50 55
Speed (miles/hour)
-------
n
i
to
c
•^
TO
o
m
x
01
•o^
0)
•o
CD
ro
a.
ro
O
O
m
3
w'
w
o'
(A
O
o
3
a.
o
CD
K
55
50
45
40-
a 35
(U
(d
30-
w 25
£
•2 20
•rH
6 15
10-
5
0
CO Emissions vs. Speed
Model Year 1985
MOBILE3
i
0
i
5
i
10
15 20 25 30 35 40 45 50 55
55
-50
-45
-40
-35
-30
-25
-20
-15
-10
5
0
Speed (miles/hour)
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/8-91-032
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
MOBILE4 Sensitivity Analysis
5. REPORT DATE
April 1991
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Mark G. Smith and Terry T. Wilson
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Alliance Technologies Corporation
100 Europa Drive, Suite 150
Chapel Hill. North Carolina 27514
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-D9-0173, Tasks 0/109
and 1/106
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Air and Energy Engineering Research Laboratory
Research Triangle Park, North Carolina 27711
13. TYPE OF REPORT AND PERIOD COVERED
Final; 4/90-3/91
14. SPONSORING AGENCY CODE
EPA/600/13
15.SUPPLEMENTARY NOTES AEERL project officer is Carl T. Ripberger, Mail Drop 62, 919/
541-2924.
i6.ABSTRACTThe report identifies the MOBILE4 input variables that can have significant
impacts on highway vehicle emissions inventories and gives priorities for the devel-
opment of improved guidance for specifying MOBILE4 inputs. Two major factors
are considered: (l) the likelihood and potential range of variability in values for
each MOBILE4 input; and (2) the potential magnitude of the effect of these variations,
in terms of impact on typical mobile source inventories. The analysis updates pre-
vious work based on MOBILES by using MOBILE4 for the sensitivity analysis and by
adding new MOBILE4 variables. The approach used in previous work is modified to
address the specific concerns of this project—the State Implementation Plan (SIP)
and National Emissions Data System (NEDS) inventory/guidance context. An addi-
tional level of detail is included for two critical variables (speed and temperature).
Sensitivity to basic vehicle inspection/maintenance program specifications (waiver
and compliance rate) is also considered. The primary sensitivity analysis is
structured around two base cases representing ozone and carbon monoxide (C) sea-
son conditions. The report describes: (1) MOBILE4 input variable values for the
ozone and CO base cases, (2) the variables and ranges or alternate values applied
in the sensitivity analysis, (3) sensitivity analysis results, and (4) conclusions.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
COSATI Field/Group
Pollution Inventories
Mathematical Models
Sensitivity Ozone
Emission Carbon Monoxide
Analyzing
Highway Transportation
Pollution Control
Mobile Sources
MOBILE4
Sensitivity Analysis
13 B
12 A
14G 07B
14B
15E
18. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (This Report)
Unclassified
21. NO. OF PAGES
45
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
-pA Form 2220-1 (9-73)
C-5
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