Historical and Future Ozone Simulations 

using the MM5/SMOKE/CMAQ System 

in the Portland/Vancouver Area 

Prepared by 

Ying Xie and Brian Lamb 

Laboratory for Atmospheric Research 

Department of Civil & Environmental Engineering 

Washington State University 

Prepared for 

Oregon Department of Environmental Quality 

Southwest Clean Air Agency 

Washington State Department of Ecology 

December 31, 2005 

1
Table of contents 

1 Executive Summary..................................................................................................................... 3 

2 Introduction.................................................................................................................................. 5 

3 Ozone Modeling Study Goal and Design .................................................................................... 5 

3.1 Previous Ozone Modeling Work ...........................................................................................5 

3.1.1 Maintenance Plan EKMA modeling.............................................................................. 6 

3.1.2 Southwest Washington Ozone Study............................................................................. 6 

3.1.3 NW Regional Technical Center Demonstration Project................................................ 6 

4 Episode Selection......................................................................................................................... 7 

5 Meteorological modeling............................................................................................................. 9 

5.1 Modeling methods .................................................................................................................9 

5.2 Meteorological modeling results and evaluation (July 1998 episode).................................12 

5.2.1 Surface Temperature.................................................................................................... 12 

5.2.2 Surface winds............................................................................................................... 16 

5.2.3 Soil moisture ................................................................................................................ 19 

5.2.4 PBL height and vertical profile.................................................................................... 21 

5.2.5 MM5 statistical evaluation........................................................................................... 27 

5.2.6 LSM run compared with simple soil model run .......................................................... 28 

5.3 Modeling results and evaluation (July 1997 episode)..........................................................29 

5.4 Back trajectory analysis.......................................................................................................35 

6 Photochemical air quality modeling .......................................................................................... 37 

6.1 Modeling methods ...............................................................................................................37 

6.2 CMAQ modeling results and evaluation (July 1998 episode).............................................39 

6.2.1 CMAQ statistics evaluation ......................................................................................... 47 

6.2.2 Comparisons with NOx/VOC monitoring data............................................................ 52 

6.3 CMAQ modeling results and evaluation (July 1997 episode).............................................58 

6.3.1 CMAQ statistics evaluation ......................................................................................... 64 

6.3.2 Comparisons with NOx monitoring data ..................................................................... 69 

6.4 Conclusion for July 1998 and 1997 CMAQ simulation ......................................................76 

7 Future episode modeling (2015)................................................................................................ 76 

7.1 Future year base case ...........................................................................................................76 

7.1.1 CMAQ modeling results.............................................................................................. 76 

7.1.2 VOC/NOx ratios and regional increase of ozone ........................................................ 83 

7.2 What if scenario - No lower Columbia River point sources................................................86 

Reference ...................................................................................................................................... 93 

Appendix A. Emission Inventory Documentation........................................................................ 95 

Appendix B: Area Source Category Emission Calculation Methodologies............................... 108 

Appendix C: MOBILE6.2 input files for the 1997 and 1998 episodes. ..................................... 111 

Appendix D: Acronyms............................................................................................................. 125 

2
1 Executive Summary 

In order to develop quantitative estimates of ozone levels in future years, a modeling study was 

completed for the Portland, OR, and Vancouver, WA urban region. This work was conducted as 

part of the State Implementation Plan development for this area. Two historical episodes (July 

17-21, 1997 and July 26-28, 1998) were simulated using the Mesoscale Meteorological model 

version 5/ Sparse Matrix Operator Kernel Emissions Modeling System / Community Multi-scale 

Air Quality Modeling System (MM5/SMOKE/CMAQ). These two episodes were selected for 

this modeling work because the July 1998 episode had the highest ozone levels observed in 

recent years for the airshed and the July 1997 episode had slightly different meteorological 

patterns compared to the 1998 case. In addition to the normal ozone observations, VOC/NOx 

monitoring data were also available for the July 1997 episode for comparison to the modeled 

results. 

As part of the base simulation for the July 1998 episode, tests were conducted to investigate the 

effects of using a more complex land-surface modeling option—the Noah Land Surface Model, 

LSM—within the MM5 meteorological model. In these tests, using the LSM in MM5 produced 

a better simulation of surface temperatures and generally lower and more accurate planetary 

boundary layer (PBL) heights along the west side of the Cascades compared to using the 

traditional simple soil model. As a result, air quality modeling results for ozone were also 

improved using MM5 with the LSM option. For the CMAQ simulation, model performance 

statistics for most monitoring sites were within United States Environmental Protection Agency 

(EPA) suggested 1-hr and 8-hr ozone modeling guidelines. Time series plots, scatter plots, and 

Quantile-Quantile plots also showed generally good agreement between model simulations and 

observations. .While model performance was acceptable for both episodes, the July 1998 episode 

was selected as the base for evaluation of future year (2015) managed growth maintenance 

projection simulations because observed ozone concentrations were much higher in 1998. 

Two 2015 managed growth maintenance projection simulations were modeled. The first 

simulation analyzed changes in ozone formation with the emissions inventory changes in the 

future. The second simulation was a modification of the first designed to examine the influence 

of the industrial sources located along the lower Columbia River on the ozone formation in the 

Portland/Vancouver urban area. 

The future year (2015) emission inventory was developed using growth factors depending on the 

surrogates for each source category. Federally mandated control strategies and foreseeable 

changes were also taken into account. Total emissions for all pollutants were projected to 

decrease in the 2015 emissions inventory compared to the 1998 emissions inventory. 

Furthermore, NOx emissions were projected to have a greater reduction than VOC emissions 

which resulted in an increase of the VOC/NOx emission ratio. For 1998, the entire Portland 

urban area and I-5 corridor appeared to be in the VOC-sensitive region, based upon predicted 

O3/NOx concentration ratios. For 2015, the VOC-sensitive areas were much smaller, which is 

consistent with the increased VOC/NOx ratio. A large reduction in ozone was predicted to occur 

downwind of urban Portland in 2015 CMAQ simulation results compared to the 1998 modeling 

results. The reduction of ozone levels within the urban core was less significant than at the 

downwind sites. The second projected 2015 simulation which assumed no large industrial 

activity along the lower Columbia River showed reductions up to 12 ppb at the southwestern 

3
Washington observation sites when compared to the first 2015 managed growth maintenance 

projection; sites in Oregon showed small or no differences associated with this simulation. 

Further analysis of other potential control strategies, based upon modifications to the 2015 

managed growth maintenance projection, will be conducted by ODEQ and SWCAA as part of 

the overall maintenance plan development. 

4
2 Introduction 

The current 1-Hour Ozone Maintenance Plans for the Portland/Vancouver airshed were adopted 

as part of the Oregon and Washington State Implementation Plans in 1997. The control 

measures in those plans have helped the region maintain the now-revoked 1-hour ozone National 

Ambient Air Quality Standard (NAAQS). The region is also in attainment of the 8-hour ozone 

NAAQS, the current ozone standard. 

However, due to exceedances of the 1-hour ozone standard in the recent past, the unique 

meteorological influences from the Columbia River Gorge, and the potential for ozone precursor 

transport in the region, regional air regulatory agencies proposed performance of photochemical 

modeling for the area as a basis for improving our understanding of the potential for ozone 

exceedances in the future. This report presents the results of this modeling study. The modeling 

system used for this work was the MM5/SMOKE/CMAQ system; it was applied to a domain 

consisting of 4 km x 4 km horizontal grid cells covering an area that extended from north of 

Puget Sound to south of Salem, OR and from the Pacific coast on the west to beyond the 

Cascade Mountain range on the east. The modeling work involved simulation of two historical 

episodes, July 17-21, 1997 and July 26-28, 1998. The model results were compared to available 

observations, and then the 1998 episode was used as a basis for evaluation of future year (2015) 

managed growth projections. An important aspect of the modeling study was the evaluation of 

model sensitivity to use of different land/surface models within the MM5 meteorological model. 

Results from these sensitivity studies are also described in this report. 

3 Ozone Modeling Study Goal and Design 

The overall goal for this work was to improve understanding of ozone behavior in the 

Portland/Vancouver airshed and to obtain model results to help evaluate future year conditions 

and the effectiveness of potential control strategies. The approach involved the following steps: 

1) selection of suitable ozone episodes that represented worst-case or typical ozone conditions, 2) 

development of the necessary meteorological, emissions, and air quality observations data sets, 

3) optimization of the modeling system to yield acceptable model performance for these 

episodes, and 4) use of the meteorological simulation from one of these episodes as a basis for 

evaluation of future year conditions and control strategy effectiveness. This work was guided by 

the Portland/Vancouver ozone modeling technical committee consisting of representatives from 

Oregon Department of Environmental Quality (ODEQ), Southwest Clean Air Agency 

(SWCAA), Washington State Department of Ecology (Ecology), the U.S. Environmental 

Protection Agency (EPA), and Washington State University (WSU). 

3.1 Previous Ozone Modeling Work 

There have been only limited ozone modeling efforts for the Portland/Vancouver area. The 1990 

Clean Air Act (CAA) Amendments classified the Portland/Vancouver airshed as a marginal 

ozone nonattainment area. There is no CAA requirement for a marginal ozone nonattainment 

area to perform photochemical modeling or any other attainment demonstration. Furthermore, 

5
there have not been other federal requirements for air regulatory agencies to perform ozone air 

quality modeling in the Portland/Vancouver airshed. The only ozone modeling work that has 

been performed has been a result of special project work or large-scale regional modeling efforts 

that included the Portland/Vancouver airshed in the overall domain. 

3.1.1 Maintenance Plan EKMA modeling

The redesignation request/ozone maintenance plans that were submitted to the Oregon and 

Washington SIPs in 1996 relied on historical ozone monitoring data, future control measures, 

and emission inventory projections to demonstrate future attainment with the 1-hour ozone 

standard. The ozone modeling work for that submittal was limited to a determination of 

emission levels necessary to prevent future exceedances using the Empirical Kinetics Modeling 

Approach (EKMA). This work utilized the Ozone Isopleth Plotting Package with Optional 

Mechanisms (OSIPM-4) to conduct the EKMA analysis. 

3.1.2 Southwest Washington Ozone Study

Following EPA’s approval of the Portland and Vancouver ozone SIP submittals, WSU was 

contracted by Ecology and SWCAA to conduct a photochemical modeling study of the area to 

determine the potential effects of point sources upwind of the Portland/Vancouver maintenance 

area on the area’s monitored ozone values. The main purpose of the study was to address the 

question of the impact of the emissions from the major industrial point sources in Cowlitz 

County, WA on ozone levels in the Portland/Vancouver maintenance area. This study also had 

an objective to help develop the regional photochemical modeling system. This included 

running the MM5 prognostic weather model and the CALGRID/CALMET suite of models with 

a fine resolution grid (5 km). The study focused on an ozone episode during July 11-14, 1996. 

The final report for this study was published in January of 1999 and is available for review on 

the Ecology website. 

3.1.3 NW Regional Technical Center Demonstration Project

This work was the result of a multi-agency collaborative effort to develop regional air quality 

modeling capabilities. The contributing agencies for this work were EPA Region 10, Ecology, 

ODEQ, Idaho Department of Environmental Quality and Environment Canada. The main goal 

of this project was to establish a virtual technical center and to demonstrate the use of the EPA 

CMAQ regional modeling system. The agencies contracted with WSU to run several CMAQ 

and CALGRID runs with varying chemical mechanisms and MM5 grid scales. This has been the 

most extensive modeling exercise that has encompassed the Portland/Vancouver region to date. 

Several modeling runs were completed to look at ozone and visibility at a 12 km grid scale. The 

model runs focused on two events, July 2-14, 1996 and July 23-30, 1996. The work was 

conducted from early 2000 to June 2002. Further details are in O’Neill and Lamb (2004); 

O’Neill et al. (2005); and Chen (2002). 

These ozone modeling studies provided the basis for the design of the current modeling project. 

In particular, the demonstration and evaluation of CMAQ in these previous studies were very 

valuable for the current study. Details describing the episode selection and modeling methods 

are given in the following sections. 

6
4 Episode Selection 

The Portland/Vancouver Maintenance Area has had relatively mild ozone seasons during the 

summers of 1999, 2000, 2001, and 2002. There were monitored exceedances of the 1-hour 

ozone standard in 1996 and 1998. There were also times of elevated ozone levels during most 

years when the standard was not exceeded. 

General EPA guidance for episode selection recommends analyzing observed meteorological 

patterns to determine which have caused violations for the area in the past. The 

Portland/Vancouver ozone modeling technical committee recommended modeling one scenario 

of each of the major meteorological situations that cause exceedances. 

The following episodes were suggested as potential episodes to model. 

 July 11-14, 1996 (Same episode used for the NWRTC Demonstration Project and the 

Southwest Ozone Study, one 1-hour ozone exceedance in the Portland area) 

 July 22-31, 1998 (Series of 3 exceedances in the Portland area during the 25th through 

the 28th) 

 July 17-22, 1997 (Episode with moderate monitored values under the 8-hour standard 

at the Portland/Vancouver monitors but well monitored) 

 July 22-26, 1996 (Episode with the highest ozone measurements in the area for 1996, 

1997, and 1998) 

 August 7-10, 1996 (Episode with Sauvie Island monitor reaching its highest value for 

1996) 

The Portland/Vancouver ozone modeling technical committee considered several factors during 

selection of the episodes to be modeled, including: 

 Ozone episodes selected for modeling should be selected from the most frequent, 

typical, and representative patterns associated with high ozone in the region. 

 Recent episodes are preferred over older episodes because recent episodes represent 

the current emissions inventory, including mobile and point configurations. Recent 

episodes can also be more representative of current reduction strategies. 

 Well-monitored episodes (with more meteorology, VOC, and NOx data) are 

preferred over data poor episodes. Additional data allow for more thorough model 

evaluation and provide information necessary to understand the processes leading to 

high ozone. 

 Ozone episodes should be selected with high monitored values to represent the 

meteorology that results in severe ozone. Furthermore, episodes should have high 

ozone in the geographical areas where high values typically occur. Such selection 

will allow modeling potential control strategies with representative ozone 

concentrations in the areas where the strategies must work. 

 Multi-day episodes are the most efficient way to model both long range transport of 

ozone and the accumulation of local emissions that are associated with ozone. 

7
 Multi-day episodes also allow the possibility of testing model responsiveness. If the 

model can reproduce both the high and low ozone days within a period, there will 

be more confidence in the model and its ability to replicate and forecast events. 

The Portland/Vancouver ozone modeling technical committee screened the suggested episodes 

based on the considerations listed above and recommended two episodes. The recommended 

episodes are as follows: 

July 22-31, 1998 was selected to be the first episode modeled. The July 1998 episode accounted 

for 3 exceedances of both the 1-hour and 8-hour ozone standards at the Carus monitor in the 

Portland area within a short period of time. There was also a near exceedance of the 1-hour 

standard and an exceedance of the 8-hour standard at the Milwaukie monitor. There were 

elevated temperatures over the series of days and light NW winds. The 1998 episode was chosen 

instead of the July 11-14, 1996 episode because considerable analysis has already been done for 

the 1996 episode, and there would be more benefit from analyzing a new episode. Table 1 

shows some select data from the 1998 episode. 

Table 1: Selected peak ozone concentrations during the July 22-31, 1998 episode (ppb) 

Milwaukie Carus 

Date 1-hour 8-hour 1-hour 8-hour 

July 26 124 100 136 117 

July 27 133 86 

July 28 137 98 

July 17-22, 1997 was selected to be the second episode modeled. This episode did not coincide 

with any ozone standard exceedances; however there were moderately high ozone levels 

recorded at the Milwaukie monitor. This episode also seemed to show a slightly different 

meteorological pattern than the 1998 episode as indicated by moderate values at both the 

Vancouver and Carus sites. The modeling technical committee compared this episode with the 

July 11-14, 1996 episode and decided that it would be more beneficial to focus the efforts on an 

event that has not previously been analyzed with a model in this area. Another reason for the 

selection of this episode (as opposed to 1996) is that there are additional monitoring data for 

southwest Washington obtained during an Ecology study conducted in the summer of 1997, 

1998, and part of 1999. In addition to the meteorological and ozone data on the Oregon side, in 

both 1998 and 1997, Southwest WA had four ozone sites in the domain (Woodland, Mt. View, 

Castle Rock, and Hockinson), and three NOx sites (Castle Rock, Mt.View and Woodland). 

Additionally, in 1997 HC and carbonyl measurements were taken at Castle Rock and Mt.View 

and there was one additional met site at a Bonneville Power Administration site. This additional 

monitoring in 1997 contrasts with the usual situation in southwest Washington where there is a 

lack of NOx and VOC sites and only a single ozone site. Table 2 shows some select data from 

the 1997 episode. 

8
Table 2: Summary of the July 17-22, 1997 episode ozone values (ppb) 

Mt. View 

(Vancouver) 

Milwaukie Carus Sauvie Island 

Date 1-hour 8-hour 1-hour 8-hour 1-hour 8-hour 1-hour 8-hour 

July 19 59 53 65 55 77 65 59 52 

July 20 77 62 101 73 73 68 48 38 

5 Meteorological modeling 

5.1 Modeling methods

The Mesoscale Meteorological model Version 5 (MM5, Grell et al., 1994) was used to provide 

the 3-D meteorological field for air quality modeling. Three one-way nested domains with grid 

cell horizontal sizes of 36 km, 12 km, and 4 km were applied. The two outer domains consisted 

of 98x95 and 133x151 grid cells, respectively. The innermost domain consisted of 112x112 grid 

cells which extended from north of Puget Sound in Washington to south of Salem, OR and from 

the Pacific coast on the west to beyond the Cascade Mountain range on the east. This domain 

was larger than the immediate area of Portland/Vancouver and was selected to minimize the 

influence of boundary conditions. Vertically, 38 sigma layers were specified. The 12 km and 4 

km MM5 domains are shown in Figure 1. 

To obtain meteorological fields that produced acceptable results with CMAQ in terms of ozone 

performance, several MM5 runs with different physics configurations were conducted as shown 

in Table 3. 

Table 3. MM5 configuration used for different model runs 

Runs 5-layer soil model_1 5-layer soil mode_2 LSM_1 LSM_2 

Label "_o" "base_sen" "sen_ini_LSM" "sen_ini_LSM_ns" 

Initialization NCEP GDAS ETA212 ETA212 ETA212 

Radiation Cloud-radiation CCM2 Radiation Cloud-radiation Cloud-radiation 

Moisture Simple ice Reisner 2 Simple ice Simple ice 

Surface scheme 5-layer soil model 5-layer soil model Noah LSM Noah LSM 

Cumulus scheme KF Cumulus KF Cumulus KF Cumulus KF Cumulus 

PBL scheme MRF MRF MRF MRF 

Analysis nudging of Tsfc and 

winds within boundary layer Not turned on Not turned on Not turned on Turned on 

As described later, the “LSM_1” run produced the best overall results for air quality modeling. 

In this report, this run is evaluated and compared with the original run (“5-layer soil model_1”). 

The original 5-layer soil model run was initialized using NCEP Global Data Assimilation System 

(GDAS) analysis archived on a 2.5x2.5 degree lat/long grid at every 12 hours. All other runs 

were initialized using NCEP Eta model analysis archived on a 40 km grid at every 3hrs. 

Analysis nudging was applied in the coarse domains (36 km, 12 km) and observational nudging 

was applied in the inner 4km domain. For analysis nudging, 3D nudging was employed for 

9
winds, temperature, and moisture above the PBL. Surface nudging was applied for winds and 

moisture, but not temperature. In some sensitivity runs, boundary layer 3D nudging was turned 

on for winds and surface nudging was also turned on for temperature. See Table 3 for 

configuration details. Wind speed and direction observations from about 20 surface stations 

were used for observational nudging of the winds in the inner 4 km domain. A map of these 

stations is shown in Figure 2. Data from four surface stations (Ecology sites as shown in Figure 

2) were withheld from the nudging analysis so that an independent evaluation could be 

conducted at these sites. For all runs, land use data were derived from 1 km USGS global terrain 

and land use database. 

The MM5 physics options used in the LSM run included use of the Kain-Fritsch cumulus 

parameterization scheme (Kain and Fritsch, 1993), the MRF PBL scheme (Hong and Pan, 1996), 

simple ice moisture, cloud-radiation, and Noah Land Surface Model (Chen and Dudhia, 2001). 

In some sensitivity runs, CCM2 radiation, Reisner2 moisture, and the 5-layer soil model were 

employed as shown in Table 3. It should be noted that the current configuration used in the 

University of Washington MM5 forecast system matches the configuration of the soil model run 

with the CCM2 radiation and Reisner2 moisture treatment. 

10
Figure 1. 12 and 4 km MM5 domain (D03 and D04) 

Figure2. Surface stations used in MM5 observational nudging. The stations within the box 

outlined in blue were used in nudging (expect for four ecology sites which were withheld). The 

sites within the inner box outlined in green were used in model evaluation. 

11
It has been shown that soil moisture has a significant impact on PBL parameters such as surface 

temperature and PBL height (Zhang and Anthes, 1982). These processes as well as cloud 

coverage, profiles of humidity, temperature and wind are all related to surface wetness and 

vegetation cover (Xiu and Pleim, 2001). In the traditional MM5 approach (5-layer soil model), 

soil moisture is set to constant seasonal values depending on land use type. Therefore, the 

effects of precipitation and evaporation are not treated explicitly. In contrast, the Noah LSM has 

four soil layers with the thickness of 0.1, 0.3, 0.6, and 1.0 m. It employs one canopy layer and 

prognostically solves for soil moisture and temperatures in each soil layer. As a result, the LSM 

has the ability to account for temporal and spatial changes in soil moisture due to precipitation 

and evapo-transpiration effects. 

5.2 Meteorological modeling results and evaluation (July 1998 episode)

5.2.1 Surface Temperature

Surface temperature contours from the simple soil-1 and LSM-1 runs are shown in Figure 3a and 

3b at 17 PDT on July 28, 1998. For western Washington and Oregon, the LSM run predicted 

cooler surface temperatures than the simple soil model, with only a small area around Portland 

above 35 C. In the simple soil model, the warm areas were much more extensive around the 

Puget Sound area and from Portland to Salem. In eastern Washington, the temperature patterns 

were opposite, where LSM-1 simulated warmer conditions than the simple soil model. 

 

Predicted surface temperature and cloud coverage were compared with observations as shown in 

Figure 4a-c. It appears that on the high ozone days (July 26 to July 28), the daily maximum 

temperatures predicted by both the LSM-1 and simple soil-1 models were fairly close to the 

observations at Portland and Salem. On the low ozone days (July 23 to July 25), LSM-1 showed 

better agreement with the observations which might be related to improved simulation of clouds 

on these days. However, in the northwestern part of the domain, such as at Castle Rock(Figure 

4c), diurnal variations of surface temperature in LSM-1 were too small compared to the daily 

variations in the observations. Similar patterns could also be found at some southwest sites such 

as UAO and HIO (not shown). A scatter plot (Figure 5) showed that both model runs tended to 

overestimate low temperatures and underestimate high temperatures. However, LSM-1 had 

slightly better agreement with the observations especially for the peak temperatures. 

12
Figure 2a. 

Figure 3a. Surface temperature pattern from simple soil model run for 17:00 PDT on July 28, 

1998. 

Figure 3b.. Surface temperature pattern from LSM model run for 17:00 PDT on July 28, 1998. 

13
PDX

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

7/22/98 0:00 7/23/98 0:00 7/24/98 0:00 7/25/98 0:00 7/26/98 0:00 7/27/98 0:00 7/28/98 0:00 7/29/98 0:00 7/30/98 0:00 7/31/98 0:00

temperature (C) / cloud cover (oktas)

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

cloud fraction

PDX temp_obs PDX cloud_cover PDX temp_o_1.5 PDX temp_1.5_r_sen_ini_LSM PDX cfrac_r_sen_ini_LSM PDX cfrac_o

Figure 4a. Surface temperature and cloud cover time series predicted by LSM and simple soil 

model compared with observations at Portland. 

SLE

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

7/22/98 0:00 7/23/98 0:00 7/24/98 0:00 7/25/98 0:00 7/26/98 0:00 7/27/98 0:00 7/28/98 0:00 7/29/98 0:00 7/30/98 0:00 7/31/98 0:00

temperature (C) / cloud cover (oktas)

0

1

2

3

4

5

6

7

8

9

10

cloud fraction

SLE temp_obs SLE cloud_cover SLE temp_o_1.5

SLE temp_1.5_r_sen_ini_LSM SLE cfrac_r_sen_ini_LSM SLE cfrac_o

Figure 4b. Surface temperature and cloud cover time series predicted by LSM and simple soil 

model compared with observations at Salem. 

14
Figure 4c. Surface temperature and cloud cover time series predicted by LSM and simple soil 

model compared with observations at Castle Rock. 

Castlerock

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

7/22/98 0:00 7/23/98 0:00 7/24/98 0:00 7/25/98 0:00 7/26/98 0:00 7/27/98 0:00 7/28/98 0:00 7/29/98 0:00 7/30/98 0:00 7/31/98 0:00

temperature (C) / cloud cover (oktas)

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

cloud fraction

Castlrck temp_obs Castlrck temp_o_1.5 Castlrck temp_1.5_r_sen_ini_LSM

Castlrck cloud_cover Castlrck cfrac_o Castlrck cfrac_r_sen_ini_LSM

y = 0.8242x + 5.6587

R2

 = 0.7636

y = 0.7917x + 7.5913

R2

 = 0.7583

0

5

10

15

20

25

30

35

40

45

50

0 5 10 15 20 25 30 35 40 45 50

obs (degree C)

pre (degree C)

temp1.5_old

temp1.5_sen_ini_LSM

1:1

Linear (temp1.5_sen_ini_LSM)

Linear (temp1.5_old)

Figure 5. Scatter plot of predicted surface temperature (LSM and simple soil) and observations 

from all available surface stations 

15
5.2.2 Surface winds

Surface wind patterns are shown in Figure 6a, and 6b for 17 PDT on July 28. The LSM-1 run 

predicted northerly winds along the I-5 corridor in western Washington, which veered to 

northwesterly and moved through the Portland area. As the flow went further south, there was 

some apparent convergence with the strong southwesterly onshore flow along the Oregon coast. 

In contrast, the winds from the simple soil model run showed very consistent northwesterly 

winds along the I-5 corridor. The onshore winds along the Oregon coast flowed northwesterly 

instead of southwesterly as in the LSM-1 run. Similar southwesterly onshore flows were also 

seen in other runs initialized using the Eta analysis, so this might be more related to the 

difference in initialization than in the surface scheme. 

The MM5 first layer (38 m) winds were extrapolated to 10 m using the neutral logarithmic wind 

speed profile and compared with 10 m surface station observations as shown in Figure 7. 

Predicted wind speed and direction showed reasonable agreement with the observations. Both 

runs tended to underestimate the daytime surface winds (Figure 7a, 7b, and 7c). This problem is 

well known for the MRF PBL scheme (Liu et al. 2004; Zhang et al. 2004.) and was related either 

to the underestimation of downward momentum flux or to the overestimation of friction velocity 

according to these researchers. 

Figure 6a. Surface wind pattern from simple soil model run for 17:00 PDT on July 28, 1998. 

16
Figure 6b. Surface wind pattern from LSM run for 17:00 PDT on July 28, 1998. 

PDX

0

90

180

270

360

7/22/98 0:00 7/23/98 0:00 7/24/98 0:00 7/25/98 0:00 7/26/98 0:00 7/27/98 0:00 7/28/98 0:00 7/29/98 0:00 7/30/98 0:00 7/31/98 0:00

Wd (degree)

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

Ws (m/s)

PDX wd_obs PDX Wd_o PDX Wd_r_sen_ini_LSM PDX ws_obs PDX Ws_o PDX Ws_r_sen_ini_LSM

Figure 7a. Surface wind speed and wind direction time series predicted by LSM and simple soil 

model compared with observations at Portland 

17
Figure 7b. Surface wind speed and wind direction time series predicted by LSM and simple soil 

model compared with observations at Salem. 

SLE

-90

0

90

180

270

360

7/23/98 0:00 7/24/98 0:00 7/25/98 0:00 7/26/98 0:00 7/27/98 0:00 7/28/98 0:00 7/29/98 0:00 7/30/98 0:00

Wd (degree)

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

Ws (m/s)

SLE wd_obs SLE Wd_o SLE Wd_r_sen_ini_LSM SLE ws_obs SLE Ws_o SLE Ws_r_sen_ini_LSM

Castlerock

-90

0

90

180

270

360

7/23/98 0:00 7/24/98 0:00 7/25/98 0:00 7/26/98 0:00 7/27/98 0:00 7/28/98 0:00 7/29/98 0:00 7/30/98 0:00

Wd (degree)

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

Ws (m/s)

Castlrck wd_obs Castlrck Wd_o Castlrck Wd_r_sen_ini_LSM Castlrck ws_obs Castlrck Ws_o Castlrck Ws_r_sen_ini_LSM

Figure 7c. Surface wind speed and wind direction time series predicted by LSM and simple soil 

model compared with observations at Castle Rock. 

18
19

5.2.3 Soil moisture 

In the simple soil model, soil moisture has constant seasonal values (summer or winter) defined 

as a function of land use type. Consequently, in summer most areas on the west side of the 

domain had volumetric soil moisture values of 0.3, except for urban areas where the soil 

moisture equaled 0.1. On the east side of the Cascades, most areas were much drier with soil 

moisture of 0.1 except for the irrigated land (shown in Figure 8) where soil moistures were equal 

to 0.5. 

In the LSM-1 run, soil moisture was initialized using analysis fields from the Eta model and 

solved prognostically. Figure 8 shows the predicted values from LSM-1 at 17 PDT on July 27. 

Soil moisture for each layer (0.1, 0.3, 0.6, and 1 m) is shown. It appears that soil was driest at 

the surface layer, and had more water in the deeper layers. On the west side of the Cascades, soil 

moisture varied from 0.25 at the surface to 0.3 in the deeper layers. The difference was more 

substantial on the east side of the Cascades where the water content varied from about 0.1 in the 

first layer to about 0.3 at 1 m deep. Some wet areas in the shallow soil layer are obvious in the 

lower right corner of the domain; these were the result of convective rain storms simulated in this 

run. 

Modeled soil moisture was also compared with the observations at the Wind River Canopy 

Crane research site located north of Stevenson, WA approximately 30 km from the Columbia 

River. As described on the research site web page (http://cdiac.ornl.gov/ftp/ameriflux/data/ussites/preliminary-data/Wind-River/1998/WRCCRF_met_meta_data.html), the observed values 

were measured at 30 cm using Campbell Scientific CS-615 probes. The station is located in an 

old growth forest canopy where soil moisture can be highly heterogeneous (personal 

communication, Timothy Link). However, the LSM-1 captured the drying trend in the 

observations fairly well (Figure 9). Note that this is consistent with the fact that there was little 

rainfall during the episode for most of the domain, and therefore, soil moisture was mainly 

controlled by evapotranspiration. 
Figure 8. Volumetric soil moisture defined in the simple soil model and values calculated 

in the LSM for different layers. 

Simple soil 

LSM – layer 1 (0.1 m) 

LSM – layer 2 (0.3 m)

LSM – layer3 (0.6 m) 

LSM – layer4 (1 m) 

20
Wind River

0.15

0.2

0.25

0.3

0.35

0.4

7/19/98 0:00 7/23/98 0:00 7/27/98 0:00 7/31/98 0:00

Date

Volumetic soil moisture

layer4

layer3

layer2

layer1

obs

Figure 9. Predicted and observed soil moisture at Wind River Crane site. 

5.2.4 PBL height and vertical profile 

PBL heights on the three peak ozone days are plotted in Figure 10 for the time when daily peak 

values were reached. The LSM-1 run generally predicted lower PBL heights along the west side 

of the Cascades, especially in western Washington. For this part of the domain, the peak PBL 

heights from the LSM-1 run were around 800 to 1000 m. In contrast, the simple soil-1 run 

predicted average peak heights around 1200 m in this area for all three days. Different patterns 

showed up for the east side of the Cascades where the LSM-1 generally predicted higher PBL 

heights, except for the very low heights in the lower right corner of the domain associated with 

areas of convective rainfall. 

Mixing heights estimated from upper air soundings at Salem, OR were compared to simulations 

from two models as shown in Figure 11. The LSM-1 run predicted lower PBL heights on July 

24, 25 and 27 than the simple soil-1 run. On July 26 and 28, the pattern was opposite. Compared 

to observed values (only available on July 26 to 28), both models tended to overestimate mixing 

heights by 200 to 300 m on these peak ozone days. 

21
Figure 10. Predicted PBL heights by LSM and simple soil model for July 1998 episode

22
PBL height -salem

0

500

1000

1500

2000

2500

3000

7/23/98 17:00 7/24/98 17:00 7/25/98 17:00 7/26/98 17:00 7/27/98 17:00 7/28/98 17:00 7/29/98 17:00

height (m)

SLE pbl_o SLE pbl_r_sen_ini_LSM obs

Figure 11. PBL predicted by simple soil and LSM compared with observed values for July 1998 

episode. 

Vertical profiles of temperature, wind speed, and wind direction were also compared with the 

upper air soundings at Salem at 17PDT on July 25 and July 26 as shown in Figure 12. The 

LSM-1 run captured the vertical temperature profile fairly well on July 25, whereas the simple 

soil-1 run appeared to overestimate the temperature and predicted a deeper mixed layer than the 

soundings. On July 26, both models matched the temperature profile well up to 700 m but 

predicted a deeper mixed layer than the observations. For wind speed, the LSM-1 run 

underestimated wind speeds up to 600 m and the simple soil-1 run showed some overestimation 

up to 1500 m on July 25. On July 26, both models underestimated wind speed. For wind 

direction, both models had very good performance on July 25. On July 26, the LSM-1 run 

showed better agreement with the observations below the boundary layer. 

23
Figure 12. Observed and predicted vertical profiles of temperature, wind speed and wind 

direction from the simple soil-1 and LSM-1 runs. (“old_run” refers to the simple soil-1 run, and 

“rerun” refers to the LSM-1 run) 

Salem July 25, 1998 17:00 PDT

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 10 20 30 40

Temp (degree C)

Height (m)

obs

rerun

old_run

Salem July 25, 1998 17:00 PDT

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0.00 2.00 4.00 6.00 8.00

Ws (m/s)

Height (m)

obs

rerun

old_run

24
Salem July 26, 1998 17:00 PDT

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 10 20 30 40

Temp (degree C)

Height (m)

obs

rerun

old_run

Salem July 25, 1998 17:00 PDT

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 90 180 270 360

Wd (degree)

Height (m)

obs

rerun

old_run

25
Salem July 26, 1998 17:00 PDT

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 5 10 15

Ws (m/s)

Height (m)

obs

rerun

old_run

Salem July 26, 1998 17:00 PDT

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 90 180 270 360

Wd (degree)

Height (m)

obs

rerun

old_run

26
5.2.5 MM5 statistical evaluation

The meteorological simulations were also evaluated using the mean bias and mean error for wind 

speed, direction, and temperature (Table 4). Four Ecology network sites (Castle Rock, 

Woodland, BPA, and Mt.Zion) were selected as independent sites and withheld from 

observational nudging for surface winds. The mean bias of temperature from the LSM-1 run was 

1.4C, about 1C smaller than the bias from the simple soil-1 run. The mean error of 

temperature was also smaller in the LSM-1 run compared to the simple soil-1 run (2.9C versus 

3.2C). The mean bias and mean error of wind speed and wind direction from the LSM-1 run 

(ME = 1.5 m/s for WS; ME = 50 for WD) were both larger than those from the simple soil-1 run 

(ME = 1.2 m/s for WS; ME = 40 for WD). This could be related to the underestimation of 

daytime surface winds and resulting error in the wind direction. The statistics for wind direction 

and wind speed were calculated separately for stations used for observational nudging and those 

withheld from observational nudging; these results show that model performance was similar for 

these two groups of stations. This might due to the relative low density of the surface stations 

available for observational nudging in the region. Nevertheless, for the simple soil-1 run, the 

results for obs nudging stations had slightly smaller error (38) in wind direction compared with 

the results for withheld stations (47). 

Table 4. MM5 performance statistics for July 1998 episode 

1998 Run T_bias T_error Wd_bias Wd_error Ws_bias Ws_error 

C C   m/s m/s 

TDO LSM-1 0.75 2.83 6.5 45.4 -0.90 1.57 

simple_soil_1 2.28 3.05 -1.5 28.9 -0.50 1.19 

Castle Rock LSM-1 1.33 2.88 -2.3 58.3 0.63 1.56 

simple_soil_1 2.85 3.37 -12.1 63.1 1.01 1.27 

KLS LSM-1 1.26 2.89 -9.1 34.3 0.07 1.32 

simple_soil_1 2.85 3.22 -9.4 25.4 0.37 1.16 

Woodland LSM-1 1.89 3.20 -8.5 20.2 -1.60 1.88 

simple_soil_1 2.49 3.23 -0.2 15.6 -1.00 1.46 

BPA LSM-1 2.08 3.10 -9.2 42.8 0.62 1.48 

simple_soil_1 2.95 3.39 -3.3 36.8 1.02 1.29 

VUO LSM-1 1.64 2.86 2.1 52.9 -0.36 1.28 

simple_soil_1 2.50 2.96 3.4 46.9 0.10 1.00 

PDX LSM-1 0.83 2.63 -3.6 46.8 -0.55 1.63 

simple_soil_1 1.92 2.64 5.7 36.0 -0.46 1.25 

Mt. Zion LSM-1 0.97 2.62 6.8 67.7 -0.36 1.18 

simple_soil_1 2.45 3.16 10.7 74.0 0.13 0.97 

HIO LSM-1 1.57 3.25 -18.9 52.3 -0.87 1.40 

simple_soil_1 2.97 3.58 -26.6 39.0 -0.76 1.01 

TTD LSM-1 1.46 2.71 7.3 75.1 -0.74 1.36 

simple_soil_1 2.98 3.27 25.1 54.6 -0.56 1.15 

UAO LSM-1 1.27 2.66 0.8 58.9 -0.44 1.62 

simple_soil_1 2.85 3.22 -7.8 36.9 -0.23 1.09 

27
Table 4. Cont. 

SLE LSM-1 1.65 2.88 1.7 47.6 0.04 1.77 

simple_soil_1 3.00 3.37 5.4 35.2 0.24 1.15 

average Run T_bias T_error Wd_bias Wd_error Ws_bias Ws_error 

C C   m/s m/s 

all stations LSM-1 1.39 2.88 -2.19 50.18 -0.37 1.50 

simple_soil_1 2.68 3.21 -0.90 41.03 -0.05 1.17 

Withheld stations LSM-1 1.57 2.95 -3.31 47.23 -0.18 1.53 

simple_soil_1 2.68 3.29 -1.23 47.37 0.29 1.25 

Nudged stations LSM-1 1.31 2.84 -1.63 51.66 -0.47 1.49 

simple_soil_1 2.67 3.16 -0.73 37.86 -0.23 1.13 

5.2.6 LSM run compared with simple soil model run

The differences from LSM-1 and simple_soil_1 runs are summarized below: 

1) LSM showed better simulation of surface temperatures. 

2) LSM predicted generally lower PBL heights along the west side of the Cascades on the 

peak ozone days. 

3) LSM was able to predict temporally and spatially varied soil moisture field in response to 

precipitation and evapo-transpiration. 

4) The performance for winds were slightly degraded in the LSM run compared to the 

simple soil model run due to well known problem of the MRF PBL scheme. 

5) Ozone simulation was also improved with MM5 including the Noah LSM as shown in 

the CMAQ modeling section. 

Therefore, LSM-1 run was selected for the MM5 simulation due its overall improved 

meteorological simulation and better ozone predictions. 

 

28
5.3 Modeling results and evaluation (July 1997 episode)

Surface temperature contours from MM5/MCIP are shown in Figure 13. Compared to the July 

1998 episode in which extensive high temperatures existed, the surface temperatures in 1997 

episode were considerably lower and in the range of 12-35C. There was generally good 

agreement between the predicted and observed surface temperatures and cloud coverage at 

Portland and Salem as shown in Figure 15a and b. At the KLS site (Figure 15c) located along 

the I-5 corridor in southwestern Washington, the LSM-1 run under-estimated daytime 

temperatures on most days. Nevertheless, there was a fairly large over-estimation of the daytime 

temperatures on July 20. The model also missed the overcast condition in that morning, which 

might explain the overestimate of temperature as well as ozone (shown in the ozone modeling 

section) around the area. Overall, however, the LSM-1 performance appears to be better for the 

1997 episode compared to 1998, especially for nighttime temperatures. 

The surface wind patterns in the afternoon of July 20 are shown in Figure 14. There were 

consistent northwesterly/westerly flows across western Washington and Oregon. Some 

convergence close to Milwaukie was apparent between the northwesterly and southwesterly 

winds in the simulation, which might contribute to the high ozone levels there. Surface time 

series of wind speed and wind direction are shown in Figure 16a-c. The LSM-1 run performed 

relatively well for wind direction. Similar to the 1998 episode, underestimation of daytime wind 

speeds were also the case for 1997. 

Modeled PBL heights were compared with observations at Salem as shown in Figure 17. On 

three of the four days when data were available (July 15, 17, and 22), the LSM-1 run predicted 

PBL heights were very close to the observations. On July 21, the PBL heights were 

overestimated by about 200 m. 

The LSM-1 performance statistics for the July 1997 episode are summarized in Table 5. Similar 

to the 1998 case, Ecology meteorological sites (Castle Rock, BPA, and Mt. Zion) were withheld 

from observational nudging of surface winds. Compared with the withheld stations, the stations 

used for observational nudging had a smaller mean error in wind direction (37 versus 49), but 

slightly larger mean bias and error in wind speed. Overall, the statistics for the 1997 episode 

were better than for 1998, with smaller mean error in temperature (2.1C versus 2.9C) and wind 

direction (40 versus 50). It is also worth noting that in 1997 there was a negative temperature 

bias and positive temperature bias in 1998; this which might be due to the better simulations of 

nighttime temperature in the 1997 episode. 

29
Figure 13. Surface temperature pattern from MM5 for 17:00 PDT on July 20, 1997. 

Figure 14. Surface wind pattern from MM5 for 17:00 PDT on July 20, 1997. 

30
PDX

0.00

5.00

10.00

15.00

20.00

25.00

30.00

35.00

40.00

7/15/97 0:00 7/16/97 0:00 7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PST)

Temperature (C) / Cloud cover (oktas)

0

0.5

1

1.5

2

2.5

Cloud fraction

3

3.5

4

4.5

5

PDX temp_obs PDX cloud_cover

31

Figure 15a. Surface temperature and cloud cover time series predicted by LSM compared with 

observations at Portland. 

Figure 15b. Surface temperature and cloud cover time series predicted by LSM compared with 

observations at Salem. 

PDX temp1.5 PDX cfrac

SLE

0.00

5.00

10.00

15.00

20.00

25.00

30.00

35.00

40.00

7/15/97 0:00 7/16/97 0:00 7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PST)

Temperature (C) / Cloud cover (oktas)

0

0.5

1

1.5

2

2.5

Cloud fraction

3

3.5

4

4.5

5

SLE temp_obs SLE cloud_cover SLE temp1.5 SLE cfrac
KLS

0.00

5.00

10.00

15.00

20.00

25.00

30.00

35.00

40.00

7/15/97 0:00 7/16/97 0:00 7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PST)

Temperature (C) / Cloud cover (oktas)

0

0.5

1

1.5

2

2.5

Cloud fraction

3

3.5

4

4.5

5

KLS temp_obs KLS cloud_cover

Figure15c. Surface temperature and cloud cover time series predicted by LSM compared with 

observations at KLS. 

Figure 16a. Surface wind speed and wind direction time series predicted by LSM compared with 

observations at Portland. 

KLS temp1.5 KLS cfrac

PDX

0

90

180

270

360

7/15/97 0:00 7/16/97 0:00 7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PDT)

Wd (degree)

0.00

5.00

10.00

15.00

20.00

25.00

30.00

35.00

Ws (m/s)

PDX wd_obs PDX Wd PDX ws_obs PDX Ws

32
Figure 16b. Surface wind speed and wind direction time series predicted by LSM compared with

observations at Salem. 

SLE

0

90

180

270

360

7/15/97 0:00 7/16/97 0:00 7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PDT)

Wd (degree)

0.00

5.00

10.00

15.00

20.00

25.00

30.00

35.00

Ws (m/s)

SLE wd_obs SLE Wd SLE ws_obs SLE Ws

KLS

0

90

180

270

360

7/15/97 0:00 7/16/97 0:00 7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PDT)

Wd (degree)

0.00

5.00

10.00

15.00

20.00

25.00

30.00

35.00

Ws (m/s)

KLS wd_obs KLS Wd KLS ws_obs KLS Ws

Figure 16c. Surface wind speed and wind direction time series predicted by LSM compared with 

observations at KLS. 

33
PBL height - Salem

0

500

1000

1500

2000

2500

7/14/97 17:00 7/15/97 17:00 7/16/97 17:00 7/17/97 17:00 7/18/97 17:00 7/19/97 17:00 7/20/97 17:00 7/21/97 17:00 7/22/97 17:00 7/23/97 17:00

Date (PDT)

Height (m)

SLE_pbl_obs

SLE pbl

Figure 17. PBL predicted by LSM compared with observed values for July 1997 episode. 

Table 5. MM5/MCIP performance statistics for July 1997 episode 

1997 Run T_bias T_error Wd_bias Wd_error Ws_bias Ws_error 

 C C   m/s m/s 

TDO LSM-1 -0.63 1.74 -9.1 36.1 -1.37 1.74 

Castle Rock LSM-1 -0.16 1.93 2.4 54.4 0.15 1.25 

KLS LSM-1 -1.02 1.82 -20.6 36.4 -0.37 1.42 

BPA LSM-1 0.32 2.04 -3.3 29.7 0.36 1.35 

PDX LSM-1 -1.49 2.14 -4.7 29.8 -1.26 1.71 

Mt. Zion LSM-1 N/A N/A -2.5 63.1 -0.11 1.24 

DLS LSM-1 -3.50 3.67 -1.7 35.2 -0.99 2.16 

HIO LSM-1 -1.42 1.96 -22.4 32.2 -0.29 1.50 

TTD LSM-1 -1.44 2.33 29.1 41.3 -0.93 1.48 

UAO LSM-1 -0.39 1.56 -1.4 42.3 -0.82 1.51 

SLE LSM-1 -0.32 1.74 6.3 44.7 -0.87 1.66 

average Run T_bias T_error Wd_bias Wd_error Ws_bias Ws_error 

 C C   m/s m/s 

all stations LSM-1 -1.01 2.09 -2.54 40.49 -0.59 1.55 

withheld stations LSM-1 0.08 1.98 -1.15 49.09 0.13 1.28 

nudged stations LSM-1 -1.28 2.12 -3.06 37.26 -0.86 1.65 

34
5.4 Back trajectory analysis 

An analysis of back trajectories for the Portland urban area was conducted by Ecology using the 

MM5 wind fields (Bowman, personal communication) and the Vis5D software package. This 

analysis was done at an early stage of the modeling work, and therefore, the simple soil-1 runs 

were used for both episodes. On each day from July 26 to 29 in 1998 and July 18 to 21 in 1997, 

two 12-hr back trajectories starting 13 PDT and 17 PDT were produced for each monitoring site. 

The trajectories terminated at 150 meters above the surface to avoid being kept in the surface 

layer. The length of time a parcel spends along the path was accumulated if the parcel was 

within 500 meters of the surface. This height was selected to accommodate seasonal and diurnal 

variations in the mixed layer. 

Two summary plots with all available back trajectories for 1998 and 1997 are shown in Figure 

18a and b. The plots show that for both years the air parcels spent a relatively long time in the 

immediate area due to the low wind speeds that existed. In 1998, most back trajectories 

originated from the north and northwest with a few exceptions coming from the southwest. It 

appeared that there was no direct impact from the Puget Sound area in that year. Compared to 

1998, winds in 1997 were more varied. In addition to trajectories from northwest/north and 

southwest, there were also trajectories that originated from the northeast in the Puget Sound 

region. 

18a. Summary plots of back trajectories during July 26 to 29, 1998. 

35
18b. Summary plots of back trajectories during July 18 to 21, 1997. 

36
6 Photochemical air quality modeling 

6.1 Modeling methods

EPA Models-3 Community Multi-scale Air Quality (CMAQ) Modeling System (Byun and 

Ching, 1999) version 4.3 was used for photochemical air quality modeling. Based on state-ofscience techniques, CMAQ is a multi-scale, multi-pollutant air quality model that simulates the 

transportation, transformation, and deposition of atmospheric pollutants including as 

photochemical precursors and oxidants, particulate matter, and airborne toxics. It incorporates 

the output fields from the MM5/MCIP meteorological simulations and emissions derived from 

the Sparse Matrix Operator Kernel Emissions Modeling System (SMOKE) 

(http://cf.unc.edu/cep/empd/products/smoke/index.cfm), and then simulates the chemical 

transport using the CMAQ Chemical Transport Model (CCTM). 

Initial and boundary conditions were primarily derived from GEOS-CHEM global model 

simulations (personal communication, Rob Elleman). However, vertical ozone IC/BC 

concentrations were derived from a combination of data sources. For the western boundary, 

ozone levels were based on Trinidad Head ozonesondes data collected during July 98 (personal 

communication, Dan Jaffe). For the other three sides (north, east, and south), ozone 

concentrations were derived from ICTC global model simulations (personal communication, 

Youhua Tang). The concentrations of each model species were height dependent. The 

concentrations in the first model layer are shown in Table 6. The CMAQ modeling domain is 

slightly smaller than the MM5 innermost domain with 99x99 horizontal grid cells at 4 km x 4 km 

spacing and with 22 layers in the vertical. The SAPRC99 photochemical mechanism including 

aqueous chemistry but no aerosol dynamics was employed. The aerosol module was not 

employed because of the lack of emission inventory data for key aerosol precursors. The 

chemical speciation of the emission inventory was performed by SMOKE according to the 

SAPRC99 mechanism. The Modified Euler Backward Interactive (MEBI) solver was used to 

solve the chemical kinetic equations. The first two days of each episode were run twice as model 

spinup to minimize the effects of initial conditions. 

37
Table 6. Initial and boundary conditions for CMAQ run (first layer) 

Species Description East North South West 

(ppbV) (ppbV) (ppbV) (ppbV) 

HCHO Formaldehyde 1.98E+00 9.21E-01 1.11E+00 2.01E-01 

ALD 

Acetaldehyde and higher 

aldehydes 1.39E+00 5.03E-01 7.80E-01 3.30E-02 

OP1 Methyl hydrogen peroxide 6.03E-01 5.45E-01 7.43E-01 8.22E-01 

KET Ketones 7.51E+00 4.52E+00 4.69E+00 1.92E+00 

ONIT Organic nitrate 2.69E-02 1.96E-02 1.23E-02 2.07E-03 

ETH Ethane 1.46E+00 1.25E+00 1.27E+00 1.03E+00 

HC3 

Alkanes w/ 2.7x10-13 > 

kOH < 3.4x10-12 3.35E-01 2.10E-01 2.06E-01 6.26E-02 

HC5 

Alkanes w/ 3.4x10-12 > 

kOH < 6.8x10-12 2.70E+00 2.70E+00 2.70E+00 1.39E+00 

HC8 

Alkanes w/ kOH > 

6.8x10-12 5.00E-01 5.00E-01 5.00E-01 1.29E-01 

OL2 Ethene 5.00E-01 5.00E-01 5.00E-01 1.50E-01 

OLT Terminal olefins 2.00E-01 2.00E-01 2.00E-01 8.71E-02 

OLI Internal olefins 4.00E-01 4.00E-01 4.00E-01 4.30E-02 

TOL 

Toluene and less reactive 

aromatics 4.00E-01 4.00E-01 4.00E-01 2.14E-01 

XYL 

Xylene and more reactive 

aromatics 5.00E-01 5.00E-01 5.00E-01 3.70E-01 

PAN 

Peroxyacetyl nitrate and 

higher PANs 1.55E-01 1.20E-01 5.89E-02 3.24E-03 

ISO Isoprene 4.00E+00 1.46E+00 3.08E+00 2.06E-02 

MACR Methacrolein 3.30E-01 1.23E-01 2.12E-01 1.03E-03 

MVK Methyl Vinyl Ketone 3.82E-01 1.61E-01 2.31E-01 1.38E-03 

MPAN 

PAN analogue formed 

from Methacrolein 5.83E-02 3.71E-02 2.67E-02 2.67E-04 

NO2 Nitrogen dioxide 5.67E-01 5.09E-01 1.90E-01 1.17E-02 

NO Nitric oxide 8.69E-02 5.92E-02 2.29E-02 1.17E-03 

O3 Ozone 4.00E+01 4.00E+01 4.00E+01 2.34E+01 

HNO3 Nitric acid 8.30E-01 3.38E-01 3.42E-01 1.37E-02 

HNO4 Peroxynitric acid 1.86E-03 1.91E-03 5.50E-04 5.01E-05 

NO3 Nitrogen trioxide 1.00E-01 1.00E-01 1.00E-01 1.00E-01 

H2O2 Hydrogen peroxide 2.35E+00 1.26E+00 1.55E+00 9.37E-01 

CO Carbon monoxide 1.45E+02 1.21E+02 1.17E+02 8.64E+01 

N2O5 Nitrogen pentoxide 1.47E-03 1.82E-03 1.87E-04 2.28E-05 

SO2 Sulfur dioxide 5.00E-02 5.00E-02 5.00E-02 3.00E-02 

SULF Sulfuric acid 3.00E-01 3.00E-01 3.00E-01 2.99E-01 

38
6.2 CMAQ modeling results and evaluation (July 1998 episode)

The local ozone monitoring sites are shown in Figure 19. Simulated surface ozone contours 

from the LSM-1 run for July 28 are shown in Figure 20 at hour 6, 10, 14, and 18 PDT. At 6 

PDT, nitric oxide (NO) titration effects were obvious within the urban core and along the I-5 

corridor with ozone concentrations below 20 ppb. At 10 PDT, ozone increases were evident 

south of Seattle with values above 60 ppb. However, there was no evident ozone production 

downwind of Portland at that hour. At 14 PDT, ozone values above 100 ppb were simulated 

immediately north and south of the Portland urban core. Maximum ozone concentrations were 

simulated at 18 PDT, with the maximum predicted ozone concentration reaching 149 ppb south 

of Portland. 

Figure 19. Ozone monitoring site map for Southwest Washington and Oregon. 

39
Figure 20. Simulated surface ozone contour on July 28, 1998 at 6, 10, 14, and 18 PDT. 

40
41
Observed and simulated 1-hr surface ozone concentration time series are shown in Figure 21. 

Note that the first two days (July 24 and 25) were used as model spinup, so the results are not 

included in the statistical evaluation. All monitoring sites except Hockinson and Wishram are 

located along the I-5 corridor. Extending from North to South, Castle Rock, Woodland, and 

Sauvie Island are rural sites situated north of Portland; Mt View and Milwaukie are two 

suburban sites, close to Vancouver and slightly southeast of downtown Portland respectively; 

Carus, another rural site, is located about 30 miles south of Portland at the foot of the mountains; 

and Turner, the most southern site within the domain, is close to Salem, OR. Hockinson and 

Wishram are the two sites that are further away from I-5 and influenced heavily by complex 

terrain close to the west slope of the Cascade Mountains and along the east edge of the Columbia 

River Gorge, respectively. 

At Castle Rock, Woodland, Sauvie Island, and Mt View, the maximum observed ozone 

concentrations were close to 100 ppb during July 26 to 28. Nighttime ozone titration was 

obvious at Sauvie Island and Mt View with concentrations decreasing to near zero. At these four 

sites, the model simulated the ozone peaks reasonably well, although sometimes the duration of 

elevated ozone in the simulations was longer than in the observations. 

At Milwaukie, observation data were missing on July 27 and part of July 26 and 28. The 

available data show an exceedance of the 1-hr standard on July 26 with maximum value of 124 

ppb. (NAAQS 1-hr ozone = 120 ppb, 8-hr ozone = 80 ppb). The LSM-1 run underestimated the 

peak ozone on July 26 and slightly overestimated it on July 28. At Carus, a series of three 

exceedances of the 1-hr and 8-hr ozone standards occurred on July 26 through 28, with 1-hr peak 

values of 136, 133, and 137 ppb, respectively. Nighttime ozone at Carus remained about 20 ppb 

because it was not affected by local NOx sources. Compared to the observations, the LSM-1 run 

missed the maximum ozone on the July 26 but captured the peaks fairly well on the following 

two days. The nighttime values were also well simulated, but the timing of the daytime peaks 

were slightly delayed in the simulations. At Turner, there was very good agreement between the 

observed and simulated ozone concentrations although nighttime ozone was overestimated. 

The model performance was different at the complex terrain sites of Wishram and Hockinson. 

At Wishram, ozone values were moderate throughout the episode with maximum value of 77 

ppb on July 27. The LSM-1 run performed reasonably well at this site. At Hockinson, 

moderately high ozone values (close to 100 ppb) were observed. However, the LSM-1 run 

seemed unable to capture the ozone peaks from July 26 to 28. 

42
Figure 21. Observed and simulated 1-hr surface ozone concentrations for July 1998 episode 

Castlerock

0

0.02

0.04

0.06

0.08

0.1

0.12

7/24/98 0:00 7/24/98 12:00 7/25/98 0:00 7/25/98 12:00 7/26/98 0:00 7/26/98 12:00 7/27/98 0:00 7/27/98 12:00 7/28/98 0:00 7/28/98 12:00 7/29/98 0:00

Date (PDT)

Ozone (ppm)

O3_1hr_obs_CR O3_1hr_sen_ini_LSM_CR

Woodland

0

0.02

0.04

0.06

0.08

0.1

0.12

7/24/98 0:00 7/24/98 12:00 7/25/98 0:00 7/25/98 12:00 7/26/98 0:00 7/26/98 12:00 7/27/98 0:00 7/27/98 12:00 7/28/98 0:00 7/28/98 12:00 7/29/98 0:00

Date (PDT)

Ozone (ppm)

O3_1hr_obs_WD O3_1hr_sen_ini_LSM_WD

43
Sauvie Island

0

0.02

0.04

0.06

0.08

0.1

0.12

7/24/98 0:00 7/24/98 12:00 7/25/98 0:00 7/25/98 12:00 7/26/98 0:00 7/26/98 12:00 7/27/98 0:00 7/27/98 12:00 7/28/98 0:00 7/28/98 12:00 7/29/98 0:00

Date (PDT)

Ozone (ppm)

O3_1hr_obs_SI O3_1hr_sen_ini_LSM_SI

Mt. View

0

0.02

0.04

0.06

0.08

0.1

0.12

7/24/98 0:00 7/24/98 12:00 7/25/98 0:00 7/25/98 12:00 7/26/98 0:00 7/26/98 12:00 7/27/98 0:00 7/27/98 12:00 7/28/98 0:00 7/28/98 12:00 7/29/98 0:00

Date (PDT)

Ozone (ppm)

O3_1hr_obs_MV O3_1hr_sen_ini_LSM_MV

44
Milwaukie

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

7/24/98 0:00 7/24/98 12:00 7/25/98 0:00 7/25/98 12:00 7/26/98 0:00 7/26/98 12:00 7/27/98 0:00 7/27/98 12:00 7/28/98 0:00 7/28/98 12:00 7/29/98 0:00

Date (PDT)

Ozone (ppm)

O3_1hr_obs_MW O3_1hr_sen_ini_LSM_MW

Carus

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

7/24/98 0:00 7/24/98 12:00 7/25/98 0:00 7/25/98 12:00 7/26/98 0:00 7/26/98 12:00 7/27/98 0:00 7/27/98 12:00 7/28/98 0:00 7/28/98 12:00 7/29/98 0:00

Date (PDT)

Ozone (ppm)

O3_1hr_obs_CA O3_1hr_sen_ini_LSM_CA

45
Turner

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

7/24/98 0:00 7/24/98 12:00 7/25/98 0:00 7/25/98 12:00 7/26/98 0:00 7/26/98 12:00 7/27/98 0:00 7/27/98 12:00 7/28/98 0:00 7/28/98 12:00 7/29/98 0:00

Date (PDT)

Ozone (ppm)

O3_1hr_obs_TN O3_1hr_sen_ini_LSM_TN

Hockinson

0

0.02

0.04

0.06

0.08

0.1

0.12

7/24/98 0:00 7/24/98 12:00 7/25/98 0:00 7/25/98 12:00 7/26/98 0:00 7/26/98 12:00 7/27/98 0:00 7/27/98 12:00 7/28/98 0:00 7/28/98 12:00 7/29/98 0:00

Date (PDT)

Ozone (ppm)

O3_1hr_obs_HK O3_1hr_sen_ini_LSM_HK

46
Wishram

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

7/24/98 0:00 7/24/98 12:00 7/25/98 0:00 7/25/98 12:00 7/26/98 0:00 7/26/98 12:00 7/27/98 0:00 7/27/98 12:00 7/28/98 0:00 7/28/98 12:00 7/29/98 0:00

Date (PDT)

Ozone (ppm)

O3_1hr_obs_WR O3_1hr_sen_ini_LSM_WR

6.2.1 CMAQ statistics evaluation 

CMAQ model performance was evaluated by the following set of ozone statistics based on the 

simulations from July 26 to 28. 

1) Normalized bias and normalized gross error between observed and predicted 1-hr/8-hr 

ozone concentrations. Data within a selected time window were used in evaluation (10-

19 PDT for 1-hr and 14-23 PDT for 8-hr ozone; shown in Table 7). These time windows 

were selected to encompass periods of elevated ozone. 

2) Normalized bias between observed and predicted 8-hr daily maxima using spatially 

paired means. (Shown in Table 8) 

3) Normalized bias between observed and predicted 8-hr daily maxima using all data pairs. 

(Shown in Table 9) 

4) Correlation coefficients and scatter plots of observed and predicted 8-hr daily maxima 

using spatially paired means. (Shown in Figure 22) 

5) Quantile-quantile plots of observed and predicted 8-hr daily maxima using (a) all data 

pairs (b) spatially paired means. (Shown in Figure 23a and 23b) 

The normalized gross error is defined as: 



 

N

i i

ii

O

OP

N

NE

1

1 ||

and the normalized bias is defined as: 

47


 

N

i i

ii

O

OP

N

NB

1

1

At Castle Rock, Woodland, and Sauvie Island, located upwind of Portland, the LSM-1 run had a 

positive bias especially at Woodland and Sauvie Island (1-hr NB of 24% and 28%, respectively). 

This could be related to the fact that simulated ozone peaks are slightly broader than the 

observed ones. For spatially paired means, the normalized bias between observed and predicted 

8-hr daily maxima are all below 20% at these sites, which meets EPA suggested guidelines 

(EPA, 1999). Nevertheless, if evaluated on a daily basis (as shown in Table 9), there was a 

larger positive bias especially on July 28. 

Mt. View and Milwaukie are two urban sites within the Portland/Vancouver airshed. At Mt. 

View, the normalized bias and gross error were reasonable (1-hr NB = 2%, 8-hr NB = 3%, 1-hr 

NE = 34%, 8-hr NE = 26%). For 8-hr daily maxima, the bias between the observed and 

predicted is generally negative when evaluated at the exact grid point of the monitoring site. 

However, when evaluated using the surrounding 5x5 matrix of grid cells, the bias becomes 

positive as a result of steep horizontal ozone gradients around the site. Due to missing data at 

Milwaukie, no statistics were calculated for this site. 

At Carus and Turner, downwind of Portland, observed ozone peaks were generally well 

simulated as shown in the bias between observed and predicted 8-hr daily maxima. However, 

the timing of the ozone peaks were slightly shifted at Carus, and consequently, the gross error 

was moderately high (1-hr NE = 36% and 8-hr NE = 27%). 

Hockinson and Wishram are two sites further away from the I-5 corridor and influenced heavily 

by complex terrain. The performance statistics were fairly good at Wishram. At Hockinson, 

performance was poor with large underprediction. Nevertheless, there were also steep horizontal 

ozone gradients around Hockinson so that the predicted 8-hr maxima are considerably higher 

when evaluated with the surrounding 5x5 grids. 

Table 7. Normalized bias and normalized gross error between observed and predicted 1-hr/8-hr 

ozone concentrations. (1-hr statistics are calculated within 10-19 PDT, and 8-hr statistics are 

calculated within 14-23 PDT on July 26, 27, and 28, 1998.) 

Site 1-hr NB 1-hr NE 8-hr NB 8-hr NE 

Castle Rock 12% 24% 9% 16% 

Woodland 24% 31% 23% 26% 

Sauvie Island 28% 36% 24% 27% 

Mt. View 2% 34% 3% 26% 

Milwaukie N/A N/A N/A N/A 

Carus 4% 36% 2% 27% 

Turner 10% 29% 5% 16% 

Wishram -6% 13% -6% 9% 

Hockinson -17% 36% -15% 28% 

Note: Values higher than EPA suggested model performance goal are highlighted in red. 

48
Table 8. Normalized bias between observed and predicted 8-hr daily maxima using spatially 

paired means. (based on 5x5 and 1x1 grids) 

site 

Ave obs 

8-hr daily max 

(ppm) 

Ave pre 8-hr daily max 

1x1 (ppm) NB (1x1) 

Ave pre 8-hr daily 

max 5x5 (ppm) NB (5x5) 

Castle Rock 0.075 0.079 4% 0.081 8% 

Woodland 0.071 0.080 13% 0.082 16% 

Sauvie Island 0.071 0.081 14% 0.083 16% 

Mt. View 0.075 0.066 -12% 0.083 11% 

Milwaukie N/A 0.085 N/A 0.092 N/A 

Carus 0.101 0.096 -5% 0.098 -3% 

Turner 0.084 0.085 0% 0.088 5% 

Wishram 0.061 0.056 -9% 0.057 -7% 

Hockinson 0.078 0.059 -24% 0.069 -12% 

Note: “1x1” – data extracted from the exact grids. 

“5x5” – data extracted from the surrounding 5x5 grids. 

Table 9. Normalized bias between observed and predicted 8-hr daily maxima using all data pairs. 

(based on 5x5 and 1x1 grids) 

Site Date 

Obs 8-hr daily max

(ppm) 

Pre 8-hr daily max 

1x1 (ppm) NB (1x1) 

Pre 8-hr daily max 

5x5 (ppm) NB (5x5) 

Castle Rock July 26 0.077 0.073 -6% 0.075 -3% 

Castle Rock July 27 0.077 0.088 14% 0.091 17% 

Castle Rock July 28 0.072 0.075 5% 0.079 10% 

Woodland July 26 0.069 0.071 2% 0.073 5% 

Woodland July 27 0.089 0.091 2% 0.091 2% 

Woodland July 28 0.054 0.079 47% 0.083 55% 

Sauvie_Island July 26 0.074 0.069 -7% 0.070 -4% 

Sauvie_Island July 27 0.078 0.090 15% 0.090 16% 

Sauvie_Island July 28 0.063 0.086 37% 0.087 39% 

Mt_View July 26 0.071 0.060 -15% 0.076 7% 

Mt_View July 27 0.078 0.064 -17% 0.086 10% 

Mt_View July 28 0.076 0.072 -5% 0.088 16% 

Milwaukie July 26 N/A 0.082 N/A 0.086 N/A 

Milwaukie July 27 N/A 0.085 N/A 0.091 N/A 

Milwaukie July 28 N/A 0.087 N/A 0.098 N/A 

Carus July 26 0.117 0.088 -25% 0.090 -23% 

Carus July 27 0.088 0.093 5% 0.097 10% 

Carus July 28 0.098 0.107 9% 0.107 9% 

Turner July 26 0.076 0.070 -8% 0.074 -3% 

Turner July 27 0.098 0.095 -3% 0.101 3% 

Turner July 28 0.078 0.089 13% 0.089 14% 

Wishram July 26 0.060 0.054 -10% 0.055 -8% 

Wishram July 27 0.063 0.054 -14% 0.056 -11% 

Wishram July 28 0.061 0.058 -4% 0.059 -2% 

49
Table 9. cont. 

Hockinson July 26 0.070 0.054 -23% 0.062 -12% 

Hockinson July 27 0.083 0.058 -30% 0.069 -16% 

Hockinson July 28 0.082 0.066 -19% 0.075 -8% 

Note: “1x1” – data extracted from the exact grids. 

“5x5” – data extracted from the surrounding 5x5 grids.

 

A scatter diagram of average observed and simulated 8-hr daily maxima (paired in space) is 

shown in Figure 22. When plotted with the surrounding 5x5 grid points, the LSM-1 run 

predicted the peak and the lowest concentrations fairly well with R2 of 0.63, but there was some 

overprediction of the moderate values (70-80 ppb). When looking at the exact grid cell, there 

was more scatter around the moderate ozone concentrations. 

Quantile-Quantile plots (Figure 23a and 23b) are also plotted for the observed and simulated 8-hr 

daily maxima which compares the frequency distributions of the observed and predicted ozone 

concentrations. The plots show generally good agreement between the observed and predicted 

concentration distributions, but there was some underperdiction of the peak ozone and 

overprediction of moderate ozone (80-90 ppb) when evaluated using the range of concentrations 

within the 5x5 surrounding grid points. When looking the exact grid point, the bias was similar 

except for some additional underprediction for the moderate concentrations (around 70 ppb). 

average predicted and obsvered 8-hr daily maxima

y = 0.8381x + 0.0155

R2

 = 0.6279

y = 0.8381x + 0.0105

R2

 = 0.5112

0.000

0.020

0.040

0.060

0.080

0.100

0.120

0.140

0.000 0.020 0.040 0.060 0.080 0.100 0.120 0.140

observed ozone (ppm)

predicted ozone (ppm)

1x1

5x5

1:1

Linear (5x5)

Linear (1x1)

Figure 22. Scatter plot of the average observed and predicted 8-hr daily maxima for 5x5 and 1x1 

grids for July 1998 episode 

50
Q-Q: 8-hr daily maxima (a. all data pairs)

0.000

0.020

0.040

0.060

0.080

0.100

0.120

0.140

0.000 0.020 0.040 0.060 0.080 0.100 0.120 0.140

observed ozone (ppm)

predicted ozone (ppm)

1x1

5x5

1:1

Figure 23a. Quantile-Quantile plot of observed and predicted 8-hr daily maxima using all data 

pairs for 5x5 and 1x1 grids for July 1998 episode. 

Q-Q: 8-hr daily maxima (b: spatially paired mean)

0.000

0.020

0.040

0.060

0.080

0.100

0.120

0.140

0.000 0.020 0.040 0.060 0.080 0.100 0.120 0.140

observed ozone (ppm)

predicted ozone (ppm)

1x1

5x5

1:1

Figure 23b. Quantile-Quantile plot of observed and predicted 8-hr daily maxima using spatially 

paired means for 5x5 and 1x1 grids for July 1998 episode. 

51
52

6.2.2 Comparisons with NOx/VOC monitoring data

In 1998, there were four NOx monitoring sites in southwest Washington and Oregon: Lafayette, 

Castle Rock, Woodland, and Mt. View. In addition to the three sites mentioned previously, 

Lafayette is a suburban site very close to the Milwaukie ozone monitoring site. A major 

roadway (US-26) is located about 100 m north of the Lafayette site. Predicted and observed 

NO/NO2 from 6 to 21 PDT on each day (July 26-28) are shown in Figure 24 for each monitoring 

site. 

At Lafayette, there were NO peaks in the morning associated with early morning emissions into 

a shallow mixed layer and lower NO concentrations during the remainder of the daylight hours. 

The LSM-1 run appeared to underestimate the early morning peaks and slightly overestimated 

observed levels from noon into the afternoon. NO2 concentrations were also generally high in 

the morning, and lower in the afternoon. The model captured the trend of NO2 well at most 

times, especially on July 27. At Woodland, early morning NO peaks were underestimated and 

predicted NO2 concentrations were also generally lower than the observed ones. At Castle Rock, 

both NO and NO2 were quite low and there was a lack of a distinct diurnal pattern due to its rural 

location. The LSM-1 run predicted NO well and also captured the range of NO2 values. At Mt. 

View, another urban/suburban site, the LSM-1 run underpredicted morning peaks of NO on the 

first two days, and overpredicted on the last day. Concentrations of NO2 were also overestimated 

at this site, especially for the afternoon hours. One thing worth noticing is that, the grid points of 

Mt. View and Lafayette both have fairly large NO emissions related to mobile sources, which 

might have a large impact on the predicted NO/NO2 concentrations. 

VOC measurements were also collected at Lafayette on selected days in 1998. The simulated 

and observed VOC concentrations are shown at Figure 25. The VOC data were canister 

measurements with sampling time from 5-8 and 8-11 PDT on selected days. The model values 

were converted from CMAQ output by summing of selected species (alkanes, aromatics, 

alkenes, terpenes, and isoprene). The observed NMOC was mostly within 150-200 ppbC except 

for July 28 when value of 740 ppbC was reported. The LSM-1 run simulated VOC levels 

perfectly on July 27. There was a slight underestimation on July 26. On July 28, the LSM-1 run 

missed the elevated level in the early morning and then slightly overestimated the total VOC 

concentration at 8-11 PDT. 
Figure 24. Observed and simulated NO/NO2 concentrations at Lafayette, Woodland, 

Castle Rock, and Mt. View from July 26 to 28, 1998. 

Lafayette July 26,1998

0

0.01

0.02

0.03

0.04

0.05

0.06

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Lafayette July 26, 1998

0

0.01

0.02

0.03

0.04

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Lafayette July 27,1998

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0.04

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Lafayette July 27, 1998

0

0.01

0.02

0.03

0.04

0.05

0.06

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Lafayette July 28, 1998

0

0.01

0.02

0.03

0.04

0.05

0.06

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Lafayette July 28,1998

0

0.02

0.04

0.06

0.08

0.1

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

53
Woodland July 26,1998

0

0.005

0.01

0.015

0.02

0.025

0.03

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Woodland July 26,1998

0

0.01

0.02

0.03

0.04

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Woodland July 27,1998

0

0.005

0.01

0.015

0.02

0.025

0.03

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Woodland July 27,1998

0

0.01

0.02

0.03

0.04

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Woodland July 28,1998

0

0.005

0.01

0.015

0.02

0.025

0.03

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Woodland July 28,1998

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0.04

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

54
Castlerock July 26,1998

0

0.005

0.01

0.015

0.02

0.025

0.03

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Castlerock July 26,1998

0

0.005

0.01

0.015

0.02

0.025

0.03

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Casterock July 27,1998

0

0.005

0.01

0.015

0.02

0.025

0.03

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Castlerock July 27,1998

0

0.005

0.01

0.015

0.02

0.025

0.03

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Castlerock July 28,1998

0

0.005

0.01

0.015

0.02

0.025

0.03

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Castlerock July 28,1998

0

0.005

0.01

0.015

0.02

0.025

0.03

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

55
56

Mt. View July 26,1998

0

0.01

0.02

0.03

0.04

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Mt. View July 26,1998

0

0.01

0.02

0.03

0.04

0.05

0.06

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Mt. View July 27,1998

0

0.01

0.02

0.03

0.04

0.05

0.06

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Mt. View July 27,1998

0

0.01

0.02

0.03

0.04

0.05

0.06

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Mt. View July 28,1998

0

0.025

0.05

0.075

0.1

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Mt. View July 28,1998

0

0.01

0.02

0.03

0.04

0.05

0.06

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre
Lafayette

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

7/24/98 0:00 7/25/98 0:00 7/26/98 0:00 7/27/98 0:00 7/28/98 0:00 7/29/98 0:00 7/30/98 0:00

Hour

VOC (ppmC)

Canister NMOC(ppmC) Pre_VOC

Figure 25. Simulated and observed VOC (ppmC) at Lafayette during the July 1998 episode. 

57
6.3 CMAQ modeling results and evaluation (July 1997 episode)

Surface ozone contours from the LSM-1 run are shown in Figure 26a and 26b for the afternoon 

of July 19 and 20. On July 19, elevated ozone concentrations were simulated downwind of 

Portland with maximum slightly above 100 ppb. On the next day, high level ozone was 

simulated right around the Portland urban area with maximum close to 130 ppb. 

Figure 26a. Simulated surface ozone contour on July 19, 1997 at 17PDT. 

Figure 26b. Simulated surface ozone contour on July 20, 1997 at 17PDT. 

58
Predicted and observed surface ozone time series were plotted in Figure 27 for each monitoring 

site. At Castle Rock, Woodland, and Mt. View, ozone concentrations were quite low on most 

days except July 19 when moderate concentrations (around 60 ppb) occurred. The LSM-1 run 

slightly overestimated ozone levels on July 19 and simulated most low ozone days well. 

Nevertheless, there was significant overestimation on July 20 at all three sites. As mentioned in 

the meteorological modeling section, there were also underestimation of cloud cover and 

overestimation of surface temperatures on that day around these sites, which might explain the 

large overestimation of ozone. 

At Mt. View and Milwaukie, moderate values occurred on July 19 at both sites and on July 20 at 

Mt. View. The peak 1-hr average ozone reached 101 ppb at Milwaukie on July 20, which was 

the maximum observed in this episode. The LSM-1 run simulated ozone quite well on low 

ozone days, and slightly overestimated on moderate and high days. There also appeared to be 

some time delay of the ozone peaks at these two sites. 

At Carus and Turner, ozone concentrations were around 80 ppb on July 19 and 20, and quite low 

on rest of the days. The LSM-1 run showed some overestimation but captured the overall trend 

quite well on July 19 and 20. On the low ozone days, both sites showed very good agreement 

between observations and simulations. 

At Hockinson and Wishram, ozone levels were low to moderate throughout the episode. The 

LSM-1 run simulated ozone quite well at Wishram. At Hockinson, where simulation was poor 

in the 1998 episode, model performance was better. It simulated the right level of ozone on July 

20, although the timing of the peak was shifted. 

59
Figure 27. Observed and simulated 1-hr surface ozone concentrations for July 1997 episode. 

CASTLEROCK

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PDT) 

Ozone (ppm)

CASTLEROCK_1hr_obs CASTLEROCK_1hr_sen_ini_LSM

Woodland

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

0.090

7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PDT)

Ozone (ppm)

Woodland_1hr_obs Woodland_1hr_sen_ini_LSM

60
Sauvie_Island

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

0.090

7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PDT)

Ozone (ppm)

Sauvie_Island_1hr_obs Sauvie_Island_1hr_sen_ini_LSM

Mt_View

0.000

0.020

0.040

0.060

0.080

0.100

0.120

7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PDT)

Ozone (ppm)

Mt_View_1hr_obs Mt_View_1hr_sen_ini_LSM

61
Milwaukie

0.000

0.020

0.040

0.060

0.080

0.100

0.120

7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PDT)

Ozone (ppm)

Milwaukie_1hr_obs Milwaukie_1hr_sen_ini_LSM

Carus

0.000

0.020

0.040

0.060

0.080

0.100

0.120

7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PDT)

Ozone (ppm)

Carus_1hr_obs Carus_1hr_sen_ini_LSM

62
Turner

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

0.090

0.100

7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PDT)

Ozone (ppm)

Turner_1hr_obs Turner_1hr_sen_ini_LSM

Hockinson

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

0.090

7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PDT)

Ozone (ppm)

HOCKINSON_1hr_obs HOCKINSON_1hr_sen_ini_LSM

63
Wishram

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

7/17/97 0:00 7/18/97 0:00 7/19/97 0:00 7/20/97 0:00 7/21/97 0:00 7/22/97 0:00 7/23/97 0:00

Date (PDT)

Ozone (ppm)

Wishram_1hr_obs Wishram_1hr_sen_ini_LSM

6.3.1 CMAQ statistics evaluation 

Model performance was evaluated using the performance measures based on the simulations 

from July 17 to 21. Normalized bias and normalized gross error between observed and predicted 

1-hr and 8-hr ozone concentrations are shown in Table 10. Normalized bias between observed 

and predicted 8-hr daily maxima using spatially paired means and all data pairs are shown in 

Table 11 and 12, respectively. 

The three upwind sites, Castle Rock, Woodland, and Sauvie Island, all showed positive 

normalized bias around 20% due to the large overestimation of ozone on July 20. Normalized 

bias between observed and predicted 8-hr daily maxima using spatially paired means was around 

20% if evaluated at the exact grid, and 30% using the maxima from the 5x5 grids as shown in 

Table 11. 

Mt. View and Milwaukie, the two urban sites, had a negative (1hr NB = -21%) and positive bias 

(1hr NB = 15 %), respectively. The negative bias at Mt. View was mostly due to 

underprediction on low ozone days. The two sites both had relatively large normalized errors, 

partly due to the timing shift of peaks. On July 19 and 20, the normalized bias between the 

observed and predicted 8-hr daily maxima was about 20% if evaluated at the exact grid as shown 

in Table 12. 

The run showed fairly good statistical performance at the Carus and Turner downwind sites (1-hr 

NB = 0% and -7%; 1-hr NE = 22% and 17%, respectively). Normalized bias between observed 

and predicted 8-hr daily maxima using spatially paired means or all data pairs was also mostly 

below 20%. Reasonably good performance was found at the Wishram and Hockinson sites. 

64
Table 10. Normalized bias and normalized gross error between observed and predicted 1-hr/8-hr 

ozone concentrations. (1-hr statistics are calculated within 10-19 PDT, and 8-hr statistics are 

calculated within 14-23 PDT from July 17 to 21, 1997.) 

Site 1-hr NB 1-hr NE 8-hr NB 8-hr NE 

Castle Rock 22% 37% 18% 32% 

Woodland 17% 31% 16% 27% 

Sauvie Island 22% 31% 20% 27% 

Mt. View -21% 43% -23% 36% 

Milwaukie 15% 46% 5% 27% 

Carus 0% 22% -3% 14% 

Turner -7% 17% -8% 12% 

Wishram -5% 12% -5% 9% 

Hockinson -3% 25% -1% 19% 

Note: Values higher than EPA suggested model performance goal are highlighted in red. 

Table 11. Normalized bias between observed and predicted 8-hr daily maxima using spatially 

paired means. (based on 5x5 and 1x1 grids) 

Site 

Ave obs 

8-hr daily max 

(ppm) 

Ave pre 8-hr daily 

max 1x1 (ppm) NB (1x1) 

Ave pre 8-hr daily 

max 5x5 (ppm) NB (5x5) 

Castle Rock 0.034 0.040 19% 0.044 32% 

Woodland 0.036 0.043 20% 0.045 27% 

Sauvie Island 0.036 0.044 24% 0.046 29% 

Mt. View 0.040 0.036 -10% 0.050 26% 

Milwaukie 0.038 0.044 15% 0.050 29% 

Carus 0.045 0.048 6% 0.054 21% 

Turner 0.047 0.045 -4% 0.050 7% 

Wishram 0.046 0.043 -6% 0.045 -1% 

Hockinson 0.042 0.040 -6% 0.045 6% 

Note: “1x1” – data extracted from the exact grids. 

 “5x5” – data extracted from the surrounding 5x5 grids

Table 12. Normalized bias between observed and predicted 8-hr daily maxima using all data 

pairs. (based on 5x5 and 1x1 grids) 

Site Date 

Obs 8-hr daily 

max 

(ppm) 

Pre 8-hr daily 

max 1x1 (ppm) NB (1x1) 

Pre 8-hr daily 

max 5x5 (ppm) NB (5x5) 

Castle Rock July 17 0.028 0.021 -26% 0.023 -16% 

Castle Rock July 18 0.032 0.036 11% 0.044 35% 

Castle Rock July 19 0.058 0.064 12% 0.066 15% 

Castle Rock July 20 0.028 0.056 99% 0.061 114% 

Castle Rock July 21 0.022 0.024 7% 0.028 25% 

65
Table 12. Cont. 

Woodland July 17 0.033 0.025 -24% 0.026 -20% 

Woodland July 18 0.034 0.033 -4% 0.037 6% 

Woodland July 19 0.053 0.069 29% 0.069 29% 

Woodland July 20 0.032 0.060 85% 0.067 107% 

Woodland July 21 0.026 0.027 5% 0.028 10% 

Sauvie_Island July 17 0.029 0.024 -18% 0.026 -12% 

Sauvie_Island July 18 0.033 0.036 6% 0.038 14% 

Sauvie_Island July 19 0.052 0.069 32% 0.069 32% 

Sauvie_Island July 20 0.038 0.065 71% 0.070 83% 

Sauvie_Island July 21 0.025 0.027 8% 0.028 10% 

Mt_View July 17 0.028 0.009 -68% 0.023 -17% 

Mt_View July 18 0.035 0.032 -9% 0.041 18% 

Mt_View July 19 0.053 0.052 -1% 0.070 33% 

Mt_View July 20 0.062 0.075 21% 0.091 47% 

Mt_View July 21 0.023 0.012 -48% 0.026 17% 

Milwaukie July 17 0.022 0.014 -37% 0.019 -10% 

Milwaukie July 18 0.028 0.034 22% 0.038 34% 

Milwaukie July 19 0.055 0.068 25% 0.075 38% 

Milwaukie July 20 0.073 0.089 23% 0.096 33% 

Milwaukie July 21 0.016 0.017 7% 0.020 30% 

Carus July 17 0.030 0.026 -15% 0.027 -10% 

Carus July 18 0.037 0.037 0% 0.043 16% 

Carus July 19 0.065 0.071 10% 0.080 24% 

Carus July 20 0.068 0.080 16% 0.087 27% 

Carus July 21 0.026 0.026 4% 0.035 37% 

Turner July 17 0.028 0.023 -18% 0.028 0% 

Turner July 18 0.047 0.045 -5% 0.049 3% 

Turner July 19 0.067 0.072 7% 0.075 12% 

Turner July 20 0.061 0.058 -4% 0.067 10% 

Turner July 21 0.032 0.027 -15% 0.032 2% 

Wishram July 17 0.040 0.038 -5% 0.039 -1% 

Wishram July 18 0.039 0.040 5% 0.041 7% 

Wishram July 19 0.054 0.048 -11% 0.050 -7% 

Wishram July 20 0.061 0.052 -14% 0.056 -8% 

Wishram July 21 0.037 0.038 5% 0.040 9% 

Hockinson July 17 0.035 0.027 -21% 0.029 -17% 

Hockinson July 18 0.036 0.041 15% 0.047 30% 

Hockinson July 19 0.056 0.044 -21% 0.052 -7% 

Hockinson July 20 0.057 0.054 -5% 0.062 10% 

Hockinson July 21 0.028 0.031 14% 0.033 21% 

Note: “1x1” – data extracted from the exact grids. 

 “5x5” – data extracted from the surrounding 5x5 grids. 

66
A scatter diagram of average observed and simulated 8-hr daily maxima (paired in space) are 

shown in Figure 28. Unlike the July 1998 episode in which only three peak ozone days were 

used in averaging, both low and high ozone days were included in the 1997 case. Therefore, all 

spatially paired means were within the 30-50 ppb range. When plotted using the exact grid cell, 

there was some slight overprediction. When looking at the 5x5 grid cells, ozone at most sites 

was overestimated. 

Quantile-Quantile plots (Figure 29a and 29b) are plotted for the observed and simulated 8-hr 

daily maxima using all data pairs and spatially paired means. When using all data pairs, it 

appears that the LSM-1 run tended to overpredict for moderate and high ozone levels, and 

performed better at low concentrations. When using spatially paired means, the model 

overpredicted at both the exact grid and the 5x5 grids. 

 average predicted and observed 8-hr daily maxima

y = 0.2432x + 0.0327

R2

 = 0.1137

y = 0.3808x + 0.0325

R2

 = 0.2971

0.000

0.020

0.040

0.060

0.080

0.100

0.120

0.000 0.020 0.040 0.060 0.080 0.100 0.120

observed ozone (ppm)

predicted ozone (ppm)

5x5

1x1

1:1

Linear (1x1)

Linear (5x5)

Figure 28. Scatter plot of the average observed and predicted 8-hr daily maxima for 5x5 and 1x1 

grids for July 1997 episode. 

67
Q-Q: 8-hr daily maxima (a. all data pairs)

0.000

0.020

0.040

0.060

0.080

0.100

0.120

0.000 0.020 0.040 0.060 0.080 0.100 0.120

Observed Ozone (ppm)

Predicted Ozone (ppm)

5x5

1x1

1:1

Figure 29a. Quantile-Quantile plot of observed and predicted 8-hr daily maxima using all data 

pairs for 5x5 and 1x1 grids for July 1997 episode. 

Q-Q: 8-hr daily maxima (b: spatially paired mean)

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

0.000 0.010 0.020 0.030 0.040 0.050 0.060 0.070 0.080

Observed Ozone (ppm)

Predicted Ozone (ppm)

5x5

1x1

1:1

Figure 29b. Quantile-Quantile plot of observed and predicted 8-hr daily maxima using spatially 

paired means for 5x5 and 1x1 grids for July 1997 episode.

68
69

6.3.2 Comparisons with NOx monitoring data

NOx data were available at Castle Rock, Mt. View, and Lafayette for the July 1997 ozone 

episode. Predicted and observed NO and NO2 concentrations from 6 to 21 PDT are shown for 

each site in Figure 30 for July 17-21, 1997. 

The observed NOx peaks in the 1997 episode were lower than those in the 1998 episode at Mt. 

View and Lafayette. The LSM-1 run showed a large overestimation of NO on the non-episode 

days (July 17, 18, and 21) at all three sites. In contrast, the agreement was much better for NO 

during days with elevated ozone (July 19 and 20). Note, that these were weekend days with 

smaller NO emissions from mobile sources. For NO2, the LSM-1 run showed some 

overprediction at Mt. View and Lafayette, but matched the general trend at most times. At 

Castle Rock, there was a large overestimation of NO2 on the non-episode days. 

The VOC data collected at the southwest Washington sites in 1997 were reported to have 

abnormally high levels of aromatics due to contamination issues (Westberg et al, 1998), 

therefore no comparisons were made for this episode. 
Figure 30. Observed and simulated NO/NO2 concentrations at Lafayette, Castle Rock, 

and Mt. View from July 17 to 21, 1997. 

Lafayette July 17, 1997

0

0.01

0.02

0.03

0.04

0.05

0.06

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Lafayette July 17, 1997

0

0.05

0.1

0.15

0.2

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Lafayette July 18, 1997

0

0.01

0.02

0.03

0.04

0.05

0.06

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Lafayette July 18, 1997

0

0.05

0.1

0.15

0.2

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Lafayette July 19, 1997

0

0.01

0.02

0.03

0.04

0.05

0.06

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Lafayette July 19, 1997

0

0.05

0.1

0.15

0.2

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

70
Lafayette July 20, 1997

0

0.05

0.1

0.15

0.2

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Lafayette July 20, 1997

0

0.01

0.02

0.03

0.04

0.05

0.06

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

LafayetteJuly 21, 1997

0

0.05

0.1

0.15

0.2

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

LafayetteJuly 21, 1997

0

0.01

0.02

0.03

0.04

0.05

0.06

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

71
Castlerock July 17, 1997

0

0.005

0.01

0.015

0.02

0.025

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Castlerock July 17, 1997

0

0.005

0.01

0.015

0.02

0.025

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Castlerock July 18, 1997

0

0.005

0.01

0.015

0.02

0.025

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Castlerock July 18, 1997

0

0.005

0.01

0.015

0.02

0.025

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Castlerock July 19, 1997

0

0.005

0.01

0.015

0.02

0.025

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Castlerock July 19, 1997

0

0.005

0.01

0.015

0.02

0.025

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

72
Castlerock July 20, 1997

0

0.005

0.01

0.015

0.02

0.025

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Castlerock July 20, 1997

0

0.005

0.01

0.015

0.02

0.025

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Castlerock July 21, 1997

0

0.005

0.01

0.015

0.02

0.025

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

CastlerockJuly 21, 1997

0

0.005

0.01

0.015

0.02

0.025

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

73
Mt. View July 18, 1997

0

0.02

0.04

0.06

0.08

0.1

0.12

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Mt. View July 18, 1997

0

0.01

0.02

0.03

0.04

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Mt. View July 19, 1997

0

0.02

0.04

0.06

0.08

0.1

0.12

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Mt. View July 19, 1997

0

0.01

0.02

0.03

0.04

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

Mt. View July 20, 1997

0

0.02

0.04

0.06

0.08

0.1

0.12

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Mt. View July 20, 1997

0

0.01

0.02

0.03

0.04

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

74
Mt. View July 21, 1997

0

0.02

0.04

0.06

0.08

0.1

0.12

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO (ppm)

NO_obs NO_pre

Mt. View July 21, 1997

0

0.01

0.02

0.03

0.04

6:00 9:00 12:00 15:00 18:00 21:00

Hour

NO2 (ppm)

NO2_obs NO2_pre

75
6.4 Conclusion for July 1998 and 1997 CMAQ simulation

Two historical episodes (July 17-21, 1997 and July 26-28, 1998) were selected as potential base 

episodes for this modeling work because the July 1998 episode had the highest ozone levels 

observed in recent years for the airshed and the July 1997 episode had slightly different 

meteorological patterns compared to the 1998 case. For the July 1998 episode, CMAQ model 

performance statistics for most monitoring sites were within EPA suggested 1-hr and 8-hr ozone 

modeling guidelines as shown in section 6.2.1. Time series plots, scatter plots, and QuantileQuantile plots also showed generally good agreement between model simulations and 

observations. For the July 1997 episode, the observed ozone levels were much lower than those 

in the 1998 case. The CMAQ performance for ozone was also acceptable for the 1997 run, but 

there was less accurate simulation of ozone levels at different times and locations compared to 

the 1998 case. Therefore, the July 1998 episode was selected as the base for evaluation of future 

year (2015) control strategy simulations due to higher observed ozone concentrations and better 

simulation of ozone levels. 

7 Future episode modeling (2015) 

7.1 Future year managed growth maintenance projection simulation

7.1.1 CMAQ modeling results

To investigate the impact of changes in emissions due to future growth and various control 

strategies, a year 2015 emission inventory was developed. This was then used in a model run 

with July 1998 meteorology to create a 2015 managed growth maintenance projection for ozone 

simulation. Emissions comparisons for 2015 and 1998 are shown in Table 13. For year 2015, the 

NOx emissions are reduced by 49%. In contrast, the VOC emissions reduction is only 26%, and 

consequently, the VOC/NOx ratio increases from 0.73 in 1998 to 1.06 in 2015. There are also 

41% and 16% reductions in SOx and CO emissions in 2015 compared to 1998. 

Table 13. Anthropogenic emission comparison between the 2015 managed growth maintenance 

projection and 1998 run 

 1998 2015 base Percentage change 

 Mole/day Mole/day 

VOC 1253 924 -26% 

NOx 1722 875 -49% 

SOx 166 99 -41% 

CO 23264 19455 -16% 

VOC/NOx 0.73 1.06 45% 

Note: Emissions are daily averages (July 24 –29) summed over the central domain (grid cells 10,20 to 45,55) 

Simulated ozone surface contours at 17PDT on July 28, 2015 are shown in Figure 31a. For 

comparison, the contours from the 1998 run and the difference plot between the two years are 

shown in Figure 31b and 31c, respectively. In the 2015 episode, the maximum 1-hr average 

ozone reached 128 ppb at 17 PDT on July 28 slightly south of Portland, as compared to 148 ppb 

in 1998. The areas with elevated ozone appear to be similar between the two years, although the 

76
absolute ozone values in 2015 were lower. As shown in Figure 31c, large reductions (20-30 ppb) 

mainly occur downwind of Portland extending from close to Carus to south of Salem. In 

contrast to the large decrease of ozone downwind of urban center, the change within Portland 

itself is smaller (< 15 ppb). 

Figure 31a. Simulated ozone contour at 17 PDT on July 28, 2015 

77
Figure 31b. Simulated ozone contour at 17 PDT on July 28, 1998 

Figure 31c. Ozone difference contour at 17 PDT on July 28 between 1998 and 2015 (1998 – 

2015) 

Simulated 1-hr and 8-hr surface ozone concentrations for the 2015 managed growth maintenance 

projection and July 1998 episode are shown in Figure 32 for each monitoring site. At the Castle 

Rock, Woodland, and Sauvie Island sites, there is a daytime decrease and slight night increase of 

ozone in 2015 compared to 1998. 

At Mt. View and Milwaukie, the daytime reduction is relatively small and sometimes the daily 

maxima occur slightly earlier in the future year run. On July 28, for example, the 1-hr ozone 

peak at Milwaukie is 2-hr earlier and also broader in 2015 compared to 1998. As a result, the 8-

hr maximum ozone on that day increases slightly (89 ppb versus 87 ppb) in the future year run. 

At Carus and Turner, the daytime reductions are large (up to 30 ppb at Turner), but nighttime 

ozone remains about the same level as 1998. At Wishram and Hockinson, in addition to the 

daytime decrease of ozone, nighttime values are also slightly lowered. 

78
Figure 32. Simulated 1-hr and 8-hr surface ozone concentrations for 2015 managed growth 

maintenance projection and July 1998 episode. 

Castlerock

0

0.02

0.04

0.06

0.08

0.1

0.12

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

 CASTLEROCK O3_2015_1hr CASTLEROCK O3_2015_8hr CASTLEROCK O3_98_1hr CASTLEROCK O3_98_8hr

Woodland

0

0.02

0.04

0.06

0.08

0.1

0.12

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

WOODLAND O3_2015_1hr WOODLAND O3_2015_8hr WOODLAND O3_98_1hr WOODLAND O3_98_8hr

79
Sauvie Island

0

0.02

0.04

0.06

0.08

0.1

0.12

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

Sauvie_Island O3_2015_1hr Sauvie_Island O3_2015_8hr Sauvie_Island O3_98_1hr Sauvie_Island O3_98_8hr

Mt. View

0

0.02

0.04

0.06

0.08

0.1

0.12

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

Mt_View O3_2015_1hr Mt_View O3_2015_8hr Mt_View O3_98_1hr Mt_View O3_98_8hr

80
Milwaukie

0

0.02

0.04

0.06

0.08

0.1

0.12

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

Milwaukie O3_2015_1hr Milwaukie O3_2015_8hr Milwaukie O3_98_1hr Milwaukie O3_98_8hr

Carus

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

Carus O3_2015_1hr Carus O3_2015_8hr Carus O3_98_1hr Carus O3_98_8hr

81
Turner

0

0.02

0.04

0.06

0.08

0.1

0.12

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

 Turner O3_2015_1hr Turner O3_2015_8hr Turner O3_98_1hr Turner O3_98_8hr

Hockinson

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

 HOCKINSON O3_2015_1hr HOCKINSON O3_2015_8hr HOCKINSON O3_98_1hr HOCKINSON O3_98_8hr

82
Wishram

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

Wishram O3_2015_1hr Wishram O3_2015_8hr Wishram O3_98_1hr Wishram O3_98_8hr

7.1.2 VOC/NOx ratios and regional increase of ozone

The [O3]/[NOx] concentration ratio has been shown to be a reliable indicator of O3 response to 

VOC or NOx emissions changes (Tonnesen and Dennis, 2000b). Values of the ratio < 15 

indicate the strongly radical-limited, VOC sensitive condition. Values > 46 indicate strongly 

NOx-limited and therefore NOx sensitive region (Arnold et al., 2003). The predicted 

[O3]/[NOx] contours in the afternoon of 2015 and 1998 are shown in Figure 33a and b. For 

1998, the entire Portland urban area and I-5 corridor appear to be well into the VOC-sensitive 

region. In contrast, for 2015 the VOC-limited areas are much smaller, which is consistent with 

the increased VOC/NOx ratio. This indicator helps to explain the ozone increase at Milwaukie 

in 2015. The site appears to be strongly VOC limited in the afternoon hours of 1998, and 

therefore, excess NO titrates O3 and reduces the O3 level. In 2015, [O3]/[NOx] is slightly above 

15 at the site. Being less VOC-limited and hence having less NO titration, an increase of O3 

could be expected. 

Another way to understand the regional increase of ozone is to look at process analysis output 

from CMAQ. Process analysis is a feature in CMAQ where the contributions of different 

chemical/physical processes are tracked by grid cell for each hour of simulations. For example, 

ozone chemical production rates are mapped for the two years in Figure 34a and b. In 1998 there 

is a net loss of ozone due to NOx titration in the urban core. In contrast in 2015, ozone is 

produced at a net rate of 10 to 20 ppb/hr within the urban core. Almost no NOx titration effects 

are observed in the 2015 case. Therefore, higher ozone values might occur in 2015 for the sites 

within urban center. 

83
Figure 33a. O3/NOx contour plot at 15 PDT on July 28, 2015 

Figure 33b. O3/NOx contour plot at 15 PDT on July 28, 1998 

84
Figure 34a. Ozone chemical production rates from process analysis at 15 PDT on July 28, 2015 

Figure 34b. Ozone chemical production rates from process analysis at 15 PDT on July 28, 1998 

85
7.2 What if scenario - No lower Columbia River point sources

Following the 2015 managed growth maintenance projection, a ‘what-if’ control scenario was 

formulated for analysis. The scenario assumed no lower Columbia River point sources. This 

effectively means no large industrial activity along the lower Columbia River. Emissions 

comparisons between the 2015 case and the no lower Columbia River point source case are 

shown in Table 14. There is a 6% reduction in VOC emissions and an 11% reduction in NOx 

emissions due to the removal of the lower Columbia River point sources. 

Table 14. Anthropogenic emissions comparisons between the 2015 managed growth 

maintenance projection and the no lower Columbia River point source case. 

 2015 projection 2015 no_columbia_pt Percentage change 

 Mole/day Mole/day 

VOC 924 870 -6% 

NOX 875 779 -11% 

SOX 99 55 -44% 

CO 19455 19046 -2% 

VOC/NOx 1.06 1.12 6% 

Note: Emissions are daily averages (July 24 –29) summed over the central domain (grid cells 10,20 to 45,55) 

Simulated ozone contours for the 2015 managed growth maintenance projection, the no lower 

Columbia River point source case, and the difference plots are shown in Figure 35a-c. Simulated 

1-hr and 8-hr surface ozone concentrations for the two cases are shown in Figure 36 for the sites 

with large ozone changes. A summary of VOC/NOx emission ratios and predicted 8-hr daily 

maximum ozone (from the surrounding 5x5 grids) for 1998 episode, 2015 managed growth 

maintenance projection, and 2015 no lower Columbia River point sources modification are 

shown in Table 15 and Figure 37. 

The amount of O3 reduction is up to 16 ppb for the case with no lower Columbia River point 

sources. The maximum reduction does not occur in the same region as the peak ozone is 

predicted to occur, and therefore the maximum ozone in the Portland/Vancouver airshed is not 

affected. The most affected sites are at Woodland and Sauvie Island where up to a 12 ppb 

decrease was predicted for the afternoon of June 26. At these two sites, there was also some 

increase in ozone at night due to less NO titration. At Mt View and Milwaukie, a small 

reduction was predicted, but not at the peak ozone hours. At the other sites, the changes in O3 

concentrations were almost negligible. 

Further analysis of other potential control strategies, based upon modifications to the 2015 

managed growth maintenance projection, will be conducted by ODEQ and SWCAA as part of 

the overall maintenance plan development. 

86
Figure 35a. Simulated ozone contour for 2015 no lower Columbia River point source case at 15 

PDT on July 26 

Figure 35b. Simulated ozone contour for 2015 projection at 15 PDT on July 26 

87
Figure 35c. Ozone difference plots between the 2015 managed growth maintenance projection 

and its no Lower Columbia River point sources modification at 15 PDT on July 26, 2015 

(2015 – no Lower Columbia point sources) 

88
Figure 36. Simulated 1-hr and 8-hr surface ozone concentrations for the 2015 managed growth 

maintenance projection and its no lower Columbia River point sources modification. 

Woodland

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

WOODLAND O3_2015_1hr WOODLAND O3_2015_8hr WOODLAND O3_2015_no_cpt_1hr WOODLAND O3_2015_no_cpt_8hr

Sauvie Island

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

Sauvie_Island O3_2015_1hr Sauvie_Island O3_2015_8hr Sauvie_Island O3_2015_no_cpt_1hr Sauvie_Island O3_2015_no_cpt_8hr

89
Mt. View

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

Mt_View O3_2015_1hr Mt_View O3_2015_8hr Mt_View O3_2015_no_cpt_1hr Mt_View O3_2015_no_cpt_8hr

Milwaukie

0

0.02

0.04

0.06

0.08

0.1

0.12

7/24/15 0:00 7/25/15 0:00 7/26/15 0:00 7/27/15 0:00 7/28/15 0:00 7/29/15 0:00

Date (PDT)

Ozone (ppm)

Milwaukie O3_2015_1hr Milwaukie O3_2015_8hr Milwaukie O3_2015_no_cpt_1hr Milwaukie O3_2015_no_cpt_8hr

90
Table 15. VOC/NOx ratio and predicted 8-hr daily maximum ozone (from the surrounding 5x5 

grids) for 1998 episode, 2015 projection, and 2015 no lower Columbia River modification. 

 1998 base 2015 base 2015 no_Columbia_pt

VOC/NOx 0.73 1.06 1.12 

Site Date 

Pre 8-hr daily max 

5x5 (ppm) 

Pre 8-hr daily max 

5x5 (ppm) 

Pre 8-hr daily max 5x5 

(ppm) 

Castle Rock 26-Jul 0.075 0.060 0.060 

Castle Rock 27-Jul 0.091 0.077 0.077 

Castle Rock 28-Jul 0.079 0.068 0.068 

Woodland 26-Jul 0.073 0.062 0.057 

Woodland 27-Jul 0.091 0.075 0.073 

Woodland 28-Jul 0.083 0.072 0.072 

Sauvie_Island 26-Jul 0.070 0.061 0.054 

Sauvie_Island 27-Jul 0.090 0.073 0.071 

Sauvie_Island 28-Jul 0.087 0.075 0.074 

Mt_View 26-Jul 0.076 0.071 0.070 

Mt_View 27-Jul 0.086 0.072 0.069 

Mt_View 28-Jul 0.088 0.082 0.081 

Milwaukie 26-Jul 0.086 0.084 0.084 

Milwaukie 27-Jul 0.091 0.085 0.084 

Milwaukie 28-Jul 0.098 0.095 0.095 

Carus 26-Jul 0.090 0.077 0.077 

Carus 27-Jul 0.097 0.085 0.084 

Carus 28-Jul 0.107 0.095 0.095 

Turner 26-Jul 0.074 0.060 0.059 

Turner 27-Jul 0.101 0.078 0.076 

Turner 28-Jul 0.089 0.068 0.068 

Wishram 26-Jul 0.055 0.050 0.052 

Wishram 27-Jul 0.056 0.049 0.050 

Wishram 28-Jul 0.059 0.050 0.051 

Hockinson 26-Jul 0.062 0.050 0.049 

Hockinson 27-Jul 0.069 0.059 0.059 

Hockinson 28-Jul 0.075 0.064 0.065 

mean 0.081 0.070 0.069 

max 0.107 0.095 0.095 

min 0.055 0.049 0.049 

91
0.000

0.020

0.040

0.060

0.080

0.100

0.120

0.140

Castlerock_26

Castlerock_27

Castlerock_28

Woodland_26

Woodland_27

Woodland_28

Sauvie_Island_26

Sauvie_Island_27

Sauvie_Island_28

Mt_View_26

Mt_View_27

Mt_View_28

Milwaukie_26

Milwaukie_27

Milwaukie_28

Carus_26

Carus_27

Carus_28

Turner_26

Turner_27

Turner_28

Wishram_26

Wishram_27

Wishram_28

Hockinson_26

Hockinson_27

Hockinson_28

Site

Predicted 8-hr daily max O3 (ppm)

1998 base 2015 base 2015 no_Columbia_pt

Figure 37. Predicted 8-hr daily maximum ozone (from surrounding 5x5 grids) for 1998 episode, 

2015 managed growth maintanence projection, and 2015 no lower Columbia River point source 

modification. 

92
 

References 

J.R. Arnold, R.L. Dennis and G.S. Tonnesen, 2003. Diagnostic evaluation of numerical air 

quality models with specialized ambient observations: testing the Community Multiscale Air 

Quality modeling system (CMAQ) at selected SOS 95 ground sites, Atmos. Environ. 37, pp. 

1185–1198. 

Byun, D.W., Ching, J.K.S. (Eds.), 1999. Science algorithms of the EPA Models-3 Community 

Multiscale Air Quality (CMAQ) Modeling System. EPA Report No. EPA-600/R-99/030, Office 

of Research and Development, US Environmental Protection Agency, Washington, DC. 

Chen, F., and J. Dudhia, 2001. Coupling an advanced land surface–hydrology model with the 

Penn State–NCAR MM5 modeling system. Part I: Model implementation and sensitivity. Mon. 

Wea. Rev., 129, 569–604. 

Chen, J.C. M.S. thesis, Washington State University, Department of Civil and Environmental 

Engineering, Pullman, WA, 2002. 

Grell, G.A., Dudhia, J., Stau!er, D.R., 1994. A description of the "fifth generation Penn 

State/NCAR mesoscale model (MM5). NCAR Technical Note NCAR/TN-398#STR, 138 pp. 

H. Westberg, B. Hopkins, E. Allwine and B. Lamb, 1998. Speciated VOC Measurements in 

Western Washington during the Summer of 1997, Washington State University Laboratory for 

Atmospheric Research. 

Hong, S.-Y., and H.-L. Pan, 1996. Nonlocal boundary layer vertical diffusion in a medium-range 

forecast model. Mon. Wea. Rev., 124, 2322–2339. 

Kain, J. S., and J. M. Fritsch, 1993: Convective parameterization for mesoscale models: The 

Kain–Fritsch scheme. The Representation of Cumulus Convection in Numerical Models, Meteor. 

Monogr., No. 46, Amer. Meteor. Soc., 165–170. 

Liu, Y., and co-authors, 2004: Improvements to surface flux computations in the MRF PBL 

scheme, and refinements to urban processes in the Noah Land-Surface model with the 

NCAR/ATEC Real-Time FDDA and forecast system. The 5th WRF / 14th MM5 User's 

Workshop , Boulder, CO. June 22-25, 2004. 

O’Neill, S.M.; Lamb, B.K., 2004. Inter-comparison of the Community Multi-scale Air Quality 

(CMAQ) model and CALGRID using Process Analysis. Environ. Sci. Technol., 39, 5742-5763. 

O'Neill, S., B. Lamb, J. Chen, C. Claiborn, D. Finn, S. Otterson, C. Figueroa, C. Bowman, M. 

Boyer, R. Wilson, J. Arnold, S. Aalbers, J. Slocum, C. Swab, M. Stoll, M. DuBois, and M. 

Anderson, 2005. Modeling aerosol formation and transport in the Pacific Northwest with the 

Community Multi-scale air quality (CMAQ) modeling system, Environ. Sci. & Technol. , in 

press. 

93
94

Tonnesen, G.S. and Dennis, R.L., 2000. Analysis of radical propagation efficiency to assess 

ozone sensitivity to hydrocarbons and NOX. Part II: long-lived species as indicators or ozone 

concentration sensitivity. Journal of Geophysical Research 105, pp. 9227–9241. 

U.S. EPA, (May 1999). Draft Guidance on the Use of Models and Other Analyses in Attainment 

Demonstrations for the 8-Hour Ozone NAAQS, EPA-454/R-99-004, 

http://www.epa.gov/scram001/guidance/guide/drafto3.pdf 

Vukovich, J. and T. Pierce, 2002. The Implementation of BEIS3 within the SMOKE Modeling 

Framework, In Proceedings of the 11thInternational Emissions Inventory Conference, Atlanta, 

Georgia, April 15-18, 2002. 

(Available online:www.epa.gov/ttn/chief/conference/ei11/modeling/vukovich.pdf) 

Xiu, A., and J. E. Pleim, 2001. Development of a land surface model. Part I: Application in a 

mesoscale meteorological model. J. Appl. Meteor., 40, 192–209. 

Zhang, D.-L., and R. A. Anthes, 1982. A high-resolution model of the planetary boundary 

layer—sensitivity tests and comparisons with SESAME-79 data. J. Appl. Meteor, 21, 1594–

1609. 

Zhang, D.-L., and W. Zheng, 2004: Diurnal cycles of surface winds and temperatures as 

simulated by five boundary-layer parameterizations. J. Appl. Meteor., 43, 157-169. 
Appendix A. Emission Inventory Documentation 

1998 and 1997 Methodologies 

Biogenic

Biogenic emissions were processed using BEIS v3.09 (Vukovich and Pierce, 2002). The model 

estimates VOC emissions from vegetation based on land-use categories and nitric oxide 

emissions from microbial activity based on soil types. The BEIS3 modeling system uses the 

Biogenic Emissions Landcover Database version 3 (BELD3) which consists of 1 km gridded 

data 230 land-use types. There are two steps involved in BEIS3 modeling. In the first step, the 

model inputs the BELD3 land-use data and emissions factors, and outputs gridded, normalized 

emissions (at 30C and 1000 umol m-2·s

-1 PAR). In the second step, the model uses 

meteorological data, speciation profiles, and normalized emissions generated from the previous 

step, and outputs gridded, speciated, hourly biogenic emissions. The biogenic emissions for 1998 

episode are summarized in Table A1 which shows that 58% of the VOC emissions and 2% of the 

NOx emissions are from biogenic sources in the central part of the domain that encompasses the 

Portland/Vancouver area. 

Table A1. Biogenic emissions summed over the central domain for the July 1998 episode. 

Species Biogenic emissions Total emissions Percent biogenic 

 Mole/day Mole/day % 

ALK2 643 699 92.0 

ISOPRENE 225 226 99.6 

OLE2 76 131 57.5 

TRP1 781 783 99.7 

NO 37 1673 2.2 

VOC 1724 2977 57.9 

NOX 37 1759 2.1 

Note: Emissions are daily averages (July 24 –29) summed over the central domain (grid cells 10,20 to 45,55) 

Area

The 1999 inventory, developed for submittal by Oregon to EPA for the 1999 NEI, was the 

starting point for the Oregon 1997 and 1998 area source emission inventory used for model 

validation. Using population as a surrogate, all the 1999 emissions were scaled back to estimate 

1997 and 1998 emissions for the 15 counties in the modeling domain using MS ACCESS. Table 

A2 below details the development of the fractions used for each county. In Appendix B, Table 

B1 lists the area source categories that were inventoried. 

95
Table A1: Population and Emission Ratios by County 

STATE/COUNTY July 1 July 1 99-97 County 99-98 County July 1

1997 1998 reduction fraction reduction fraction 1999

OREGON 3,217,000 3,267,550 3,300,800

BENTON 76,700 76,600 0.9948 0.9935 77,100

CLACKAMAS 317,700 323,600 0.9720 0.9901 326,850

CLATSOP 34,500 34,700 0.9928 0.9986 34,750

COLUMBIA 41,500 42,300 0.9730 0.9918 42,650

HOOD RIVER 19,200 19,500 0.9746 0.9898 19,700

JEFFERSON 17,100 17,400 0.9688 0.9858 17,650

LINCOLN 42,500 43,200 0.9804 0.9965 43,350

LINN 100,700 102,200 0.9777 0.9922 103,000

MARION 267,700 271,900 0.9726 0.9878 275,250

MULTNOMAH 639,000 641,900 0.9879 0.9923 646,850

POLK 57,400 59,500 0.9551 0.9900 60,100

TILLAMOOK 23,800 24,000 0.9876 0.9959 24,100

WASCO 22,600 22,600 0.9978 0.9978 22,650

WASHINGTON 385,000 397,600 0.9512 0.9823 404,750

YAMHILL 79,200 81,900 0.9531 0.9856 83,100

SWCAA and the Washington Department of Ecology did not have a complete 1999 area source 

submittal to start with so SWCAA built a 1998 EI for the 8 counties in the core Washington 

domain following EPA protocols as outlined in EIIP references. The eight counties in the core 

Washington domain were Clark, Cowlitz, Klickitat, Lewis, Pacific, Skamania, Wahkiakum, and 

Yakima counties. WSU staff then used 1996 area source data for the remainder of the domain 

counties from the Northwest Regional Technical Center (NWRTC) demonstration project work. 

The emission categories, and the methodologies used for calculating emissions for these 

categories are described in Appendix B. 

Nonroad Mobile

To create nonroad mobile estimates, excluding aircraft, rail and marine, for the 1997 and 1998 

episodes, DEQ and SWCAA used EPA’s 2002 NONROAD model. Collaborative care was 

taken to assure the consistency and validity of the model inputs between states and accurately 

reflect the conditions in each state. The NONROAD model allows users to design various 

scenarios to generate emissions. The period input parameters for the model runs that generated 

this data were: seasonal, typical day, summer, weekday to provide a conservative estimate of 

emissions. The 2002 NONROAD model was run for 1997 and 1998 episodes, with the same 

input parameters except for the change in year. Table A2 summarizes the fuel parameter inputs 

representing both episodes. 

96
Table A2. Oregon NONROAD model fuel parameter inputs 

1997/1998

Modeling Episode

Input Inputs

Fuel RVP 7.8

Fuel O2 wt% 2.0

Gasoline sulfur wt% 0.021

Diesel sulfur wt% 0.5

CNG/LPG sulfur wt% 0.0123

Stage II control % *

NONROAD Model fuel parameter inputs:

* Control efficiency in Multnomah, Washington, and Clackamas counties was set to 

81% based on DEQ estimates. For all other counties within the domain, the control 

efficiency was set to 0. 

Fuel RVP is the July ASTM terminal limit RVP for western Oregon and the Portland/Vancouver 

area (1997). The O2 and diesel sulfur weight % are DEQ estimates. Gasoline sulfur is from a 

state-by-state fuel properties report prepared for the EPA by ICF consulting. The CNG sulfur is 

a conservative estimate for HD5 propane rated for fuel use. 

Temperature data for Oregon counties for the 1997 and 1998 episode runs were averaged from 

the temperatures of the top ten ozone days in the three years leading up to and including the 

original base year of 1996. Temperature data were taken from the Oregon Climatological Data 

Survey. The temperatures were averaged for the episode; the results are shown in Table A3. 

Table A3. Oregon NONROAD temperature data inputs 

Avg. T Avg High T Avg. Low T

County (F) (F) (F)

BENTON 75.7 92.1 59.2

CLACKAMAS 77.0 95.9 58.2

CLATSOP 65.4 76.5 54.2

COLUMBIA 78.2 96.0 60.4

HOOD RIVER 79.3 99.2 59.5

JEFFERSON 72.2 95.4 49.0

LINCOLN 65.4 76.5 54.2

LINN 77.0 95.9 58.2

MARION 77.2 95.9 58.5

MULTNOMAH 77.7 96.0 59.5

POLK 71.8 86.3 57.3

TILLAMOOK 65.4 76.5 54.2

WASCO 79.3 99.2 59.5

WASHINGTON 77.0 94.1 59.8

YAMHILL 73.1 88.2 58.0

Temperature data for WA counties in the 1997 and 1998 episode runs were derived from NOAA 

data at various sites within those counties. The temperatures used were average temperatures 

97
during the peak days of each respected episode. Table A4 shows the temperatures used for the 8 

core counties in 1998 and for the entire WA domain in 1997. 

Table A4. WA core domain counties NONROAD temperature data inputs 

1997 Episode 1998 Episode 

Avg. High 

(F) 

Avg. Low 

(F) 

Avg. 

(F) 

Avg. High 

(F) 

Avg. Low 

(F) Avg. (F) 

Clark 78.9 52.6 65.8 86.8 58.6 72.7

Cowlitz 77.6 53.8 65.7 87.1 59.6 73.4

Klickitat 88.4 50.1 69.3 101.4 58.8 80.1

Lewis 79.9 54.0 67.0 89.1 61.4 75.3

Pacific 72.8 50.7 61.8 74.9 57.0 66.0

Wahkiakum 54.0 72.9 63.5 80.8 56.4 68.6

Skamania 80.4 47.2 63.8 92.3 57.2 74.8

Yakima 89.2 53.6 71.4 99.7 66.1 82.9

Aircraft, rail and commercial marine emissions in Oregon were estimated in the same manner as 

the area sources. They were back cast based on the population ratios between the 1999 inventory 

year and each specific episode year. ODEQ calculated the Columbia River commercial marine 

emissions and the emissions were apportioned to the Oregon counties that bordered the 

Columbia River. In Washington, aircraft and commercial marine emissions from the 1996 

NWRTC demonstration project were used because most of these emissions were outside of the 8 

county core WA domain. Washington locomotive emissions were developed by ODEQ for a 

1997 locomotive emission inventory. 

Washington Department of Ecology assisted in the Nonroad inventory work by processing the 

Nonroad model outputs for input into the SMOKE model with a customized script. 

On-road Mobile

The 1997 and 1998 mobile emissions were calculated based on episode specific, link-based, 

daily trip VMT data modeled by RTC and Metro using traffic demand models. MOBILE6.2 was 

used to calculate the emission factors with the episode-specific conditions. The summary of the 

approach to mobile emissions modeling estimates was to: 

 Create link-based daily VMT for the AQMA using traffic demand models, and 

county-wide VMT for the remainder of the domain. 

 Create four total MOBILE6.2 input files representing Clark County, Portland 

Metro Area Counties (both with I/M features); Washington State counties, and 

Oregon State counties (both without I/M features) for the remainder of the modeling 

domain. 

 Run MOBILE6.2 at a standard temperature and at individual temperatures. 

 Calculate average daily emissions at the standard temperature. 

 Create a set of temperature adjustment factors from the individual temperature runs. 

 Use SMOKE's gridded temperature file (from MM5) to apply adjustments to the 

standard emissions. 

98
This method allowed adjustment of hourly emissions based on temperature, but involved postprocessing of SMOKE data. ODEQ completed the MOBILE6.2 work with assistance from 

ECOLOGY and SWCAA for Washington data, and WSU completed the SMOKE processing. 

The eight (4 per episode year) MOBILE6.2 input files can be found in Appendix C. 

Industrial Point Sources

Industrial Point Sources from both states were loaded into a common database to ease tracking 

and model input file generation. Regional staff for Washington and Oregon compiled annual 

emission information for permitted facilities. Industrial Point sources that emit more than 10 

tons per year of VOC, 40 tons per year of NOx, or 100 tons per year of CO within the 4 counties 

of the Portland/Vancouver ozone maintenance area were inventoried for this work. Point sources 

that emit more than 40 tpy of NOx or 100 tpy of VOC or CO outside the maintenance area 

counties were also inventoried. Additionally, point sources emitting less than those thresholds 

within 4 kilometers of ozone monitoring sites were included in the episode emission inventories. 

Stack parameters, activity, and exact location were collected when available to provide the most 

comprehensive accounting possible. 

SOX emissions have an indirect influence on ozone, as such these emissions were included in the 

model run inventories. No SOX parameters were used in compiling the point source list for this 

project. The emissions were included only for sources that met the NOX, CO, and/or VOC 

thresholds described above. Facility SOX data for Washington point sources were included in 

the 1997 and 1998 runs. For Oregon, 1997 and 1998 estimated actual SOX emissions for TV 

point sources were generated from the ODEQ ACSIS point source database. The emissions were 

split by SCC, but not by stack or device. SOX data for the 2002 EI that was used to forecast 

2015 emissions estimates was included for all sources in both states. ODEQ Program Operations 

staff inventoried the emissions for TV sources; regional staff estimated the emissions for all 

other sources. 

All of these major categories were processed through SMOKE by WSU staff in preparation for 

the modeling. 

Future Year Documentation

Base Year (2002) methodology for area and point sources

The base year EI chosen to be forecasted to 2015 was the latest emission inventory that was 

created for submittal to EPA under the Consolidated Emissions Reporting Rule (CERR). This 

2002 county by county annual inventory was developed by the respective states following the 

currently accepted methodologies and submitted as part of the National Emission Inventory 

(NEI). As required by the submittal process it underwent rigorous QA by ODEQ, Ecology and 

EPA contractors. These statewide inventories covered many more pollutants than were needed 

for this ozone modeling. Therefore the ozone precursor pollutants (CO, NOx, VOC) and SOx 

99
were selected by source classification code (SCC) from the submitted inventories for the 

counties in the modeling domain. 

Area source forecast method

The selected pollutants comprising the Oregon inventory were input into a MS ACCESS 

database table to begin the future forecast. Area source forecasts were developed following a 

method that had been used in the previous Oregon SIPs following EPA guidance in Procedures 

for Preparing Emission Projections & Guidance for Growth Factors. This method involves 

creating surrogate growth factors (Table A5) for industrial, commercial, population, and 

household growth. In addition, there is a no growth option. Each SCC in the inventory is then 

assigned one of these surrogates. 

Table A5. 2015 Growth Surrogate Factors 

PSC Portland Metro CO MA Growth Factors Percent Growth Parameter Data

1 Population (Zoning & Land Use Based) 1.8% Linear, Non-Compounding

2 Housing Growth & Land Use Projections 2.0% Linear, Non-Compounding

3 Commerical Employment & Land Use Projections 1.0% Linear, Non-Compounding

4 Industrial Employment & Land Use Projections 0.2% Linear, Non-Compounding

5 Field burning, orchard heating, orchard prunning burning, RWC 0.0% No Growth

6 RR -Transportation, Communication, Utilities 1.3% Linear, Non-Compounding

The factors themselves were developed from the METRO Economic Report Regional Forecast 

for the Portland-Vancouver, OR-WA area provided by Chief Economist, Dennis Yee with 

METRO’s Data Resource Center. They represent the average growth rate for the period 2002 to 

2015 derived from the industrial and commercial employment projections, population, and 

resulting household growth. The industrial and commercial decisions were based on SIC 

grouping from Procedures for the Preparation of Emission Inventories for Carbon Monoxide 

and Precursors of Ozone, Volume I: General Guidance for Stationary Sources and represent an 

average of the following sectors. The same growth factors were used for both the Washington 

and Oregon source categories (Table A6). Although, SWCAA did look for WA specific data in 

other parts of the domain, it was decided that Portland/Vancouver area influences were the 

greatest and local planning decisions were the most influential in model results. 

The rate of growth was calculated with the following formula: 

(Future yr employment - initial yr employment)/initial employment/ # of years of growth. 

100
Table A6. 2002 to 2015 METRO Ozone Summary Industrial Growth Factor Table 

2002-2015 Industrial Categories 2002 2015 linear, non-compounding

6 Food Processing 8.35 7.71 -0.59%

7 Textiles & Apparel 3.5 3.06 -0.97%

8 Paper & Pulp 6.61 6.22 -0.45%

9 Printing & Publishing 11.4 13.47 1.40%

10 Nondur. Goods, other 7.24 10.06 3.00%

12 Lumber & Wood 7.52 5.9 -1.66%

13 Metals 18.49 19.6 0.46%

15 Nonelectrical Mach. 15.91 20.82 2.37%

16 Electrical Mach. & Instr. 43.24 59.31 2.86%

17 Transportation Equip. 9.52 11.68 1.75%

18 Durable Goods, other 8.59 11.06 2.21%

20 Constr. & Mining 53.34 71.82 2.67%

2002-2015 rate 2195.71 2255.71 0.21%

Table A7. 2002 to 2015 METRO Ozone Summary Commercial Growth Factor Table 

Commercial 2002 2015 linear, non-compounding

2 Nonfarm Self-Employ. 253.3 352.0 3.00%

22 Transport., Comm., & Util. 54.5 69.9 2.176%

24 Retail Trade 167.4 225.6 2.67%

25 Wholesale Trade 65.0 87.9 2.70%

26 Fin., Ins., & Real Est. 64.5 80.1 1.87%

28 Health 64.6 93.5 3.45%

29 Nonhealth 214.5 326.3 4.01%

30 Govt., Fed. Civilian 18.1 19.4 0.55%

31 Govt., Fed. Military 6.6 6.7 0.07%

32 Govt., State & Local 109.0 129.7 1.46%

2002-2015 rate 3,019.6 3,406.1 0.98%

Those factors were then used in the ACCESS database to estimate the 2015 emissions with the 

following equation: 

2002 base year emissions + (2002 base year emissions * growth factor * 13 growth years) 

2015 Nonroad Mobile

The NONROAD2004 model was used to estimate the 2015 emissions since it accounts for both 

growth and federal controls on covered nonroad sources. According to the May 2004 EPA FAQ 

101
on the NONROAD model, the draft NONROAD2004 model includes the following federal 

emission reduction rules: 

1) Final Tier 4 nonroad diesel engine standards (also known as the Clean Air Nonroad 

Diesel Rule), final rule. However, the model does not yet contain the evaporative 

emission benefits for the new recreational equipment and large spark-ignition 

standards. [Adjustments for the evaporative reductions were not done for this 

modeling effort.] 

2) Final nonroad diesel fuel sulfur standards associated with the Tier 4 rule 

For the 2015 Nonroad Model run inputs, all period parameters except year were retained from 

the 1997/1998 runs. 

For fuel parameter inputs, a 2015 gasoline sulfur default of 0.0030 weight % from EPA’s 

MOBILE6 was used. A 2015 diesel sulfur 0.0011 weight % was taken from the inputs for the 

NONROAD model runs EPA generated to develop the 2004 Nonroad Diesel Engine Final Rule. 

Stage II control % was set to 0 since Oregon Stage II phase out is expected to begin sometime in 

2008. The CNG/LPG sulfur weight % and all temperature data were retained from the 

1997/1998 runs. 

Fuel O2 weight % and RVP data were improved and revised for the 2015 Nonroad Model 

episode runs. Baseline oxygen weight % was revised downward, and it was determined that 

ethanol is blended year-round at some Oregon terminals. DEQ assumes that blending will 

continue through 2015, so the 2015 fuel O2 was estimated to be 1.03% by weight for all counties 

in the domain. RVP refinements were made by apportioning terminal RVP to county and 

subsequently incorporating the revised O2 weight %. The final RVP estimates are shown by 

county in Table A8. 

Table A8. 2015 Ozone Modeling Nonroad Model Input RVP – Oregon Counties 

Fuel

County RVP

Benton 9.3

Clackamas 8.1

Clatsop 9.3

Columbia 9.3

Hood River 9.3

Jefferson 9.3

Lincoln 9.3

Linn 9.3

Marion 8.6

Multnomah 8.1

Polk 8.2

Tillamook 9.3

Wasco 9.3

Washington 8.1

Yamhill 9.3

102
For the Washington portion of the modeling domain, SWCAA used the same temporal 

parameters that ODEQ used for their portion of the domain. The fuel parameters were also 

consistent with the Oregon portion of the domain except for Fuel RVP. The inputs used for WA 

counties were consistent with an internal Ecology document summarizing Mobile 6/6.2 input 

parameters for the different regions of the state entitled Mobile 6/6.1/6.2 Input Parameters and 

Processing (May 6, 2003 update). Fuel RVP values used for WA in the 2015 nonroad emissions 

modeling are shown in Table A9. 

Table A9: 2015 Ozone Modeling Nonroad Model Input RVP - Washington Counties 

County Fuel RVP County Fuel RVP

ADAMS 8.5 KITTITAS 8.5

BENTON 8.5 KLICKITAT 8.5

CHELAN 8.5 LEWIS 8.5

CLALLAM 8.5 LINCOLN 8.5

CLARK 7.8 MASON 8.5

COWLITZ 8.5 PACIFIC 8.5

DOUGLAS 8.5 PIERCE 7.8

FRANKLIN 8.5 SKAMANIA 8.5

GRANT 8.5 SNOHOMISH 7.8

GRAYS HARBOR 8.5 THURSTON 8.5

ISLAND 8.5 WAHKIAKUM 8.5

JEFFERSON 8.5 WALLA WALLA 8.5

KING 7.8 YAKIMA 8.5

KITSAP 8.5

Railroad, marine vessels, and airports are estimated independently of the NONROAD model. 

2015 locomotive and commercial marine vessel emissions were estimated by the growth factor 

analysis method similar to area sources. For locomotive engines the national average growth 

factor (1.3%) from the Federal Clean Air Nonroad Diesel – Final Rule Regulatory Impact 

Analysis Document was applied to grow the emissions. However in the 13 years separating the 

base and future years that analysis showed that the clean engine technology was working its way 

into use and lowering the emissions. The reductions from the Tier 0/I/II implementation on 

emissions work is shown in EPA’s Emission Factors for Locomotives (Document EPA420-F-97-

051 Dec. 1997) which gives fleet average emission factors for all locomotives from 1999 to 

2040. By comparing the 2002 fleet average emission factors to the 2015 fleet average emission 

factors, the effects on NOx, CO, HC, and PM are given as follows: 

Table A10. 2002 vs. 2015 Locomotive EF Ratios 

Pollutant 2015/2002 Ratio 

HC 0.794 

CO 1 

NOx 0.607 

PM 0.779 

103
These ratios were applied to the grown 2015 emissions to reflect the expected fleet penetration of 

the Tier 0-II locomotives over time. In the same manner Nonroad diesel sulfur content is 

expected to drop to 15 ppm by 2012 for locomotives and marine engines. Chapter 3 of the Clean 

Air Nonroad Diesel – Final Rule Regulatory Impact Analysis gives the anticipated changes to 

SO2 emissions. 

Table 3.1-6a on page 3-19 gives the Baseline Locomotive fuel sulfur content and Locomotive 

SO2 emissions in tpy. This ‘baseline’ sulfur content only fluctuates due to ‘spillover’ from the 

low-sulfur highway diesel. 

Table 3.4-8a on page 3-57 gives the Control Locomotive fuel sulfur content and Locomotive 

SO2 emissions in tpy. This table shows substantial reductions for the nonroad low-sulfur diesel 

impacts as well as highway diesel spillover. 

To get the 2002 and 2015 (controlled) numbers on the same basis (lb SO2/gallon diesel), each 

years annual emissions were divided by the annual fuel usage for that year from table 3.1-6a. 

This resulted in the following: 

Table A11. Locomotive Baseline and Future Fuel Usage and Emissions 

Year Fuel Usage (gal) SO2 Emissions (tpy) Rate (lb SO2/gal) 

2002 2.692 x10^9 49,291 0.03662 

2015 3.148 x10^9 1,231 0.000782 

Therefore the ratio of 2015 to 2002 SO2 emissions due to the low-sulfur fuel is equal to the ratio 

of 0.000782/0.03662 or: 

Table A12. Locomotive Sulfur Emissions Reduction Factor 

Pollutant 2015/2002 Ratio 

SO2 0.02135 

Commercial marine vessel 2015 emissions received the derived commercial growth factor 

application. The change in sulfur emissions from large trans-oceanic shipping is not yet clear so 

it was decided that there would be no reduction factor applied to the commercial marine vessel 

emissions. 

Recreational marine vessels are also calculated “off model” and so the 2002 emissions were 

grown to 2015 using population as a surrogate following the area source application method.

Aircraft emissions for the Oregon 2002 NEI submitted data had two sources. The Port of 

Portland went through great detail to prepare emissions for Hillsboro, Troutdale, Mulino, and 

Portland International airports out to the year 2020. This data was verified and accepted as part 

of the Oregon CERR submittal. Because the remaining towered airports and the many smaller 

airports do not fall under the Port’s jurisdiction they were estimated by DEQ using the Emissions 

Dispersion and Modeling System (EDMS) developed by the FAA. Therefore, the 2015 aircraft 

emissions include those estimated by the Port (where appropriate) and those grown by DEQ 

using the commercial growth factor as discussed above. 

104
In the Washington part of the modeling domain, the only significant aircraft emissions were in 

the Puget Sound region, and the most notable of these at the Seattle Tacoma International Airport 

(Sea-Tac). Emission data for that facility were compiled by a consultant (CDM) and provided to 

PSCAA. PSCAA provided these data to SWCAA for input into the model along with aircraft 

emissions for Snohomish, Pierce, and Kitsap Counties. 

2015 On-road Mobile

The 2015 mobile emissions were calculated based on link-based, daily trip VMT data modeled 

by RTC and Metro using traffic demand models. MOBILE6.2 was used to calculate the 

emission factors with the 1998 episode-specific conditions. The summary of the approach to 

mobile emissions modeling estimates was to: 

 Create link-based daily VMT for the AQMA using traffic demand models, 

 ODOT and WDOT provided county-wide VMT for the remainder of the domain. 

 Create four total MOBILE6.2 input files representing Clark County, Portland Metro 

Area Counties (both with I/M features); Washington State counties, and Oregon State 

counties (both without I/M features) for the remainder of the modeling domain. 

 Run MOBILE6.2 at a standard temperature and at individual temperatures. 

 Calculate average daily emissions at the standard temperature. 

 Create a set of temperature adjustment factors from the individual temperature runs. 

 Use SMOKE's gridded temperature file (from MM5) to apply adjustments to the 

standard emissions. 

This method allowed adjustment of hourly emissions based on temperature, but involved postprocessing of SMOKE data. ODEQ completed the MOBILE6.2 work with assistance from 

ECOLOGY and SWCAA for Washington data, and WSU completed the SMOKE processing. 

The eight (4 per episode year) MOBILE6.2 input files can be found in Appendix C. 

 

2015 Point Source Growth Factor Implementation

Point source emissions were grown using 2003 through 2015 annual growth factors supplied by 

Metro (ref 603). The growth factors are keyed by Metro number, which was cross-walked to 

Standard Industrial Classification (SIC) by DEQ staff (Marianne Fitzgerald, AQ-PPD). The 

growth factors with matched SICs are shown in Table A.13. 

105
Table A13. Point Source SIC growth rates 

SIC Industry MetroNumber 2015

20 Bakeries 6 -1.28%

26 Pulp/paper/paperboard 8 -1.11%

27 Graphic arts/printing 9 0.45%

28 Organic chemical mfg. 10 2.55%

29 Petroleum refining 10 2.55%

32 Glass products 10 2.55%

24 Sawmills 12 -3.12%

25 Furniture & Fixtures 12 -3.12%

34 Fabricated metal products 13 -0.61%

33 Iron & steel mfg 13 -0.61%

35 Machinery & computer equip. 15 0.77%

38 Photographic equipment 16 1.00%

36 Electronic equipment & components 16 1.00%

37 Transportation equipment 17 -0.09%

30 Rubber & misc. plastic products 18 1.19%

17 Construction 20 0.43%

13 Oil & Gas Extraction 20 0.43%

42 Farm product storage 22 1.55%

45 Airports 22 1.55%

49 Waste disposal 22 1.55%

52 Building materials 24 1.59%

50 Scrap & waste materials 25 1.29%

51 Gasoline storage 25 1.29%

72 Industrial laundries 29 2.50%

75 Carwashes 29 2.50%

76 Repair shops 29 2.50%

82 Colleges & Universities 29 2.50%

97 Air national guard 31 0.00%

Emissions by facility were grown by matching the facility primary SIC to the SIC in Table 

2.7.X. A linear, non-compounding formula was used: 

((Metro growth factor) * (previous year emissions)) + (previous year emissions) 

For example, for a selected SIC sub-category for the year 2003, with a 2002 (base year) value of 

10 tons per year, and growth factors of 2.5% in 2003 and 3.0 % in 2004: 

2003 tpy = (0.025 growth * 10 tpy) + (10 tpy) = 10.25 tpy 

2004 tpy = (0.03 growth * 10.25 tpy) + (10.25 tpy ) = 10.56 tpy

 Biogenic emissions will be assumed to remain unchanged in the future, although urban 

development does modify the amount, location, and type of vegetation over time. 

106
Comparisons between 1998 and 2015 future year 

Figure A1. Episode Emission Comparison 

139,585

10,334

7,519

115,186

5,269

5,516

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

Moles/episode

1998 2015

Year

Domain Anthrogenic Pollution 1998 vs 2015

VOC

SOX

NOX

CO

Summary of Assumptions and Strategies built into 2015 EI

The following is a list of the assumptions built in to the 2015 emissions inventory used for the 

modeling of the base future year scenario. 

 Railroad emissions have incorporated low sulfur fuel and the effect 

of Tier I/II engine penetration into the fleet. 

 Final Tier 4 nonroad diesel engine standards and diesel fuel sulfur 

standards associated with the rule have been included. 

 Onroad diesel sulfur was 15 ppm 

 Population increased 1.8% 

 Household growth was 2.0% 

 Commercial employment growth was 1.0% 

 Industrial employment growth was 0.21% 

107
Appendix B: Area Source Category Emission Calculation Methodologies 

Category: AREA SOURCES SCC SWCAA Methodology SWCAA Methodology

1997 & 1998 O3 Episodes 2002/2015 Future Year Episode

AREA SOURCES

 FUEL STORAGE AND TRANSPORT

Area Source Categories 25-01-000-000 Did not include Did not include

Marine Vessel Transport

Residual Oil 25-05-000-060 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Tanker - Gasoline 25-05-020-120 Contribution from Tidewater Barge Lines Contribution from Tidewater Barge Lines

Barge - Gasoline 25-05-020-121 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Jet Naphtha 25-05-000-150 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Aviation Fuel Distribution

Aircraft Fueling: Uncontrolled - Aviation Gas Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Aircraft Fueling: Controlled - Aviation Gas Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

UST Working Loss - All Fuels 22-75-900-202 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

UST Filling - All Fuels 22-75-900-201 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Truck Transport (Jet Naphtha) Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Truck Transport (Aviation Gas) Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Truck Transport (Jet Fuel) Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Vehicle Fuel Distribution

Stage I Uncontrolled 25-01-060-052 Calculated from SWCAA Database SWCAA and PSCAA data

Stage I Controlled 25-01-060-053 Calculated from SWCAA Database SWCAA and PSCAA data

Stage II Uncontrolled (doesn't exist) 25-01-060-101 Did Not Include Did Not Include

Stage II Controlled 25-01-060-102 Calculated from SWCAA Database No Stage II in out-year

UST Working Loss 25-01-060-201 These emissions included in other 25-01-060-xxx categories These emissions included in other 25-01-060-xxx categories

Truck Transport (Auto Gas) 25-05-030-120 Calculated using EIIP EF Did Not Include

 SOLVENT EVAPORATION/UTILIZATION

Surface Coating

Auto Refinishing 24-01-005-000 Actual Emissions from small source database Actual Emissions from SWCAA - EIIP for other counties

Factory Finished Wood 24-01-015-000

Wood Furniture 24-01-020-000

Paper 24-01-030-000 Not inventoried as area source (assumed point source) Not inventoried as area source (assumed point source)

Metal Cans 24-01-040-000

Metal Coils 24-01-045-000

Misc. Metals 24-01-050-000 Lumped into Industrial Coatings

Machinery & Equipment 24-01-055-000 2002 NEI data

Electronic & Other Electrical 24-01-065-000

Motor Vehicles 24-01-070-000

Marine 24-01-080-000

EIIP Chapter 8, Employees from County Business Patterns 

(SIC in 1997 and NAICS in 1998), VOC EF from Table 8.5-2.

Plastic Products 24-01-035-000 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Misc. Manufacturing 24-01-090-000 EIIP, Table 8.5-2 (9/26/97) EIIP, Table 8.5-2 (9/26/97)

Industrial Maintenance 24-01-100-000 EIIP, Table 8.5-2 (9/26/97) EIIP, Table 8.5-2 (9/26/97)

Special Purpose 24-01-200-000 EIIP, Table 8.5-2 (9/26/97) EIIP, Table 8.5-2 (9/26/97)

Traffic Markings 24-01-008-000 EIIP Chapter 14 (5/17/97), Alternative 1 EIIP Chapter 14 (5/17/97), Alternative 1

Architectural 24-01-001-000 EIIP Chapter 3 & Census/Paint and Allied Products EF dev

WDOE 2002 CERR data - EIIP Chapter 3 & Census/Paint and 

Allied Products EF dev

Surface Cleaning: Each category contains 4 subcategories

Furniture & Fixtures 24-15-005 to 305-000

Primary Metal Industries 24-15-010 to 310-000

Fabricated Metal Products 24-15-020 to 320-000

Industrial Machinery & Equipment 24-15-025 to 325-000

Electronic & Other Electrical 24-15-030 to 330-000

Transportation Equipment 24-15-035 to 335-000

Instruments & Related Products 24-15-040 to 340-000

Misc. Manufacturing 24-15-045 to 345-000

Transportation Maintenance Facilities 24-15-050 to 350-000

Automative Dealers 24-15-055 to 355-000

Auto Repair Services 24-15-065 to 365-000

Graphic Arts

All Processes & Solvents 24-25-000-000

Alternative method 2 from EIIP Chapter 7 (10/96): (SIC or 

NAICS employment) Subtract out to avoid double counting

Alternative method 2 from EIIP Chapter 7 (10/96): 

(employment surrogate) Subtract out to avoid double counting

22-75-900-101

25-05-030-180

EIIP Chapter 8, Employees from County Business Patterns 

(SIC in 1997 and NAICS in 1998), VOC EF from Table 8.5-2.

EIIP Chapter 8, Employees from County Business Patterns 

(SIC in 1997 and NAICS in 1998), VOC EF from Table 8.5-2.

EIIP Chapter 8, Employees from County Business Patterns 

(SIC in 1997 and NAICS in 1998), VOC EF from Table 8.5-2. 2002 NEI data

Methodology per SIC employee emission factors given in EIIP, 

Chapt. 6. SIC employee data obtained from County Business 

Patterns website. SIC converted to NAICS (for 1998) (EIIP 

methodology, Chapt. 8). No total (all processes) entered into 

the database to avoid double counting. Open top degreasing 

categories added. 

Methodology per SIC employee emission factors given in 

EIIP, Chapt. 6. SIC employee data obtained from County 

Business Patterns website. SIC converted to NAICS (EIIP 

methodology, Chapt. 8). No total (all processes) entered into 

the database to avoid double counting. Open top degreasing 

categories added. 

EIIP Chapter 8, Employees from County Business Patterns 

(SIC in 1997 and NAICS in 1998), VOC EF from Table 8.5-2.

EIIP Chapter 8, Employees from County Business Patterns 

(SIC in 1997 and NAICS in 1998), VOC EF from Table 8.5-2. EIIP Chapter 8, Employees from County Business Patterns 

(SIC in 1997 and NAICS in 1998), VOC EF from Table 8.5-2.

108
Miscellaneous Non-Industrial : Commercial

Cutback Asphalt 24-61-021-000

Emulsified Asphalt 24-61-022-000

Roofing Asphalt 24-61-023-000 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Pesticide Application 24-61-850-000 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Fertilizer Application-Anhydrous Ammonia 28-01-700-001 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Fertilizer Application-Aqua Ammonia 28-01-700-002 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Fertilizer Application-Nitrogen Solutions 28-01-700-003 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Fertilizer Application-Urea 28-01-700-004 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Fertilizer Application-Ammonium Nitrate 28-01-700-005 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Fertilizer Application-Ammonium Sulfate 28-01-700-006 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Fertilizer Application-Other Straight Nitrogen 28-01-700-008 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Fertilizer Application-Ammonium Phosphates 28-01-700-009 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Fertilizer Application-Nitrous oxide 28-01-700-011 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Fertilizer Application-Nitric oxide 28-01-700-012 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Miscellaneous Non-Industrial: Consumer

Coatings and Related Products 24-60-500-000 EIIP, Table 5.4-1 (8/2/96) - Population Surrogate

WDOE 2002 CERR data - EIIP, Table 5.4-1 (8/2/96) - 

Population Surrogate

Personal care 24-65-100-000 EIIP, Table 5.4-1 (8/2/96) - Population Surrogate

WDOE 2002 CERR data - EIIP, Table 5.4-1 (8/2/96) - 

Population Surrogate

Household Products 24-65-200-000 EIIP, Table 5.4-1 (8/2/96) - Population Surrogate

WDOE 2002 CERR data - EIIP, Table 5.4-1 (8/2/96) - 

Population Surrogate

Auto Aftrmkt 24-65-400-000 EIIP, Table 5.4-1 (8/2/96) - Population Surrogate

WDOE 2002 CERR data - EIIP, Table 5.4-1 (8/2/96) - 

Population Surrogate

Adhesives/Sealants 24-65-600-000 EIIP, Table 5.4-1 (8/2/96) - Population Surrogate

WDOE 2002 CERR data - EIIP, Table 5.4-1 (8/2/96) - 

Population Surrogate

Pesticide(fifra) 24-65-800-000 EIIP, Table 5.4-1 (8/2/96) - Population Surrogate

WDOE 2002 CERR data - EIIP, Table 5.4-1 (8/2/96) - 

Population Surrogate

Miscellaneous 24-65-900-000 EIIP, Table 5.4-1 (8/2/96) - Population Surrogate

WDOE 2002 CERR data - EIIP, Table 5.4-1 (8/2/96) - 

Population Surrogate

Dry Cleaning

Solvents NEC 24-20-000-999 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Perchloroethylene

1996 = 24-20-000-055 

1999 = 4-01-001-13 Did Not Include (Not a VOC) Did Not Include (Not a VOC)

 WASTE DISPOSAL, TREATMENT, & RECOVERY

Open Burning

residential, garbage 26-10-030-000

All open burning based on past SWCAA survey's and 

extrapolated based on per capita growth. (Includes residential 

brush, debris, and garbage). 2002 CERR data from WDOE

commercial 26-10-020-000 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

residential, includes leaves & brush 26-10-000-000 Lumped in with 26-10-030-000 Lumped in with 26-10-000-400

residential, brush 26-10-000-400 Lumped in with 26-10-030-000 2002 CERR data from WDOE

residential, leaves 26-10-000-100 Lumped in with 26-10-030-000 Lumped in with 26-10-030-000

Municipal Landfills

Landfills 26-20-030-000 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Landfills (TV) 5-01-004-02 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Wastewater Treatment

POTW's 26-30-020-000 Did Not Include (Included in PT sources) Did Not Include (Included in PT sources)

Leaking Underground Storage Tanks

LUST's 26-60-000-000 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

 SMALL STATIONARY FUEL & WOOD USE

ind. fuel oil (dist. & kero) 21-02-004-000 Did Not Include (Included in PT sources) Did Not Include (Included in PT sources)

ind. fuel oil (residual) 21-02-005-000 Did Not Include (Included in PT sources) Did Not Include (Included in PT sources)

industrial LPG 21-02-007-000 Did Not Include (Included in PT sources) Did Not Include (Included in PT sources)

com. fuel oil (dist. & kero) 21-03-004-000 Residential and Commercial Fuel Use Based SWCAA Factors 2002 NEI data

com. fuel oil (residual) 21-03-005-000 Residential and Commercial Fuel Use Based SWCAA Factors Lumped into 21-03-004-000

commercial LPG 21-03-007-000 Residential and Commercial Fuel Use Based SWCAA Factors 2002 NEI data

commercial natural gas 21-03-006-000 Residential and Commercial Fuel Use Based SWCAA Factors 2002 NEI data

industrial natural gas 21-02-006-000 Residential and Commercial Fuel Use Based SWCAA Factors Lumped into point sources or Commercial Nat. Gas

residential fuel oil (dist. & kero) 21-04-004-000 Residential and Commercial Fuel Use Based SWCAA Factors 2002 NEI data

residential LPG 21-04-007-000 Residential and Commercial Fuel Use Based SWCAA Factors 2002 NEI data

residential natural gas 21-04-006-000 Residential and Commercial Fuel Use Based SWCAA Factors 2002 NEI data

Throughput from Chevron (sales to SW WA), methods from 

EIIP Chapt. 17 and Chevron/ODEQ Factors 2002 NEI data

109
Residential Wood Combustion

Fireplaces 21-04-008-001 Did Not Include (Insignificant in Summer)

Catalytic Wood Stoves 21-04-008-030 Did Not Include (Insignificant in Summer)

Non-catalytic Wood Stoves 21-04-008-050 Did Not Include (Insignificant in Summer)

Convetional Wood Stoves 21-04-008-051 Did Not Include (Insignificant in Summer)

Pellet Stoves 21-04-008-053 Did Not Include (Insignificant in Summer)

 MISC. AREA SOURCES

Agricultural

Ag. field burning 28-01-500-000 Did Not Include (Insignificant in Summer) WDOE 2002 CERR data

Ag. propane burning 28-01-501-000 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Ag. stack burning 28-01-502-000 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Orchard Burning - Apples 28-01-500-320 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Orchard Burning - Cherries 28-01-500-350 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Orchard Burning - Grapes 28-01-500-500 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Orchard Burning - Hazelnuts 28-01-500-450 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Orchard Burning - Peaches 28-01-500-410 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Orchard Burning - Pears 28-01-500-420 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Orchard Burning - Prunes/Plums 28-01-500-430 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Orchard Burning - Walnuts 28-01-500-440 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Orchard Burning - Other 28-01-500-300 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Orchard Heaters - All Fuels 28-01-520-000 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Orchard Heaters - Propane 28-01-520-010 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Orchard Heaters - Diesel 28-01-520-004 Did Not Include (Insignificant in Summer) Did Not Include (Insignificant in Summer)

Other Combustion

Wildfires 28-10-001-000

Did Not Include (Checked episode dates and fire dates to assure 

these not significant) Did Not Include (Assumed Insignificant)

Prescribed Burning 28-10-015-000 Did Not Include (Assumed Insignificant) WDOE 2002 CERR data

Structure Fires 28-10-030-000 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Misc 

Commercial Charbroiling 23-02-002-000

Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Commercial Deep Fat Frying 23-02-080-001

Did Not Include (One large source included in Pt sources) Did Not Include (One large source included in Pt sources)

Hospital Sterilization 28-50-000-010 Did Not Include (Assumed Insignificant) Did Not Include (Assumed Insignificant)

Chrome Electroplating 3-09-010-XXX

Did Not Include (Insignificant) Did Not Include (Insignificant)

NONROAD MOBILE

Misc. 2-stroke, 4-stroke, Diesel 22-60,65,70-XXX-000 Nonroad 2002a Nonroad2004 model used to calculate 2015 data

Recreational Marine Vessels 22-82-XXX-XXX Nonroad 2002a Nonroad2004 model used to calculate 2015 data

Commercial Marine Vessels 22-80-002-000

Relied on OR data for Columbia, NWRTC Data for Puget 

Sound Area

ODEQ Calculated Columbia River data. WDOE 2002 CERR 

CMV data for all other counties 

Aircraft 22-75-000-000

Calculated based on SWCAA derived EF Included aircraft emissions from Puget Sound Region

Railroads 22-85-002-XXX ODEQ 1996 Research for WA state WDOE 2002 CERR Data. Applied EPA Factors to adjust for 

Tier 0-II standards and fleet turnover

ONROAD MOBILE

Onroad Mobile Emissions Mobile 6a (by ODEQ), RTC VMT, WDOE VMT Calculated directely for 2015

2002 CERR from WDOE lumped into 21-04-008-000

110
Appendix C: MOBILE6.2 input files for the 1997 and 1998 episodes. 

* Filename: ClrkIM97 -- Clark County I/M run with M6 

* This input generates the summer fleet-average VOC, CO, SOx and NOx emissions from 

CY1997 for Clark County Washington using Washington 1997 registration data (reg1997) and 

Vancouver I/M program file description (im1997.van) 

******************* Header Section ************************ 

MOBILE6 INPUT FILE 

PARTICULATES : 

SPREADSHEET : 

DATABASE OUTPUT : 

WITH FIELDNAMES : 

AGGREGATED OUTPUT : 

*REPORT FILE : 

RUN DATA 

******************* Run Section *************************** 

NO REFUELING : 

FUEL RVP : 7.8 

* enter the appropriate registration distribution filename for the county being modeled. 

REG DIST : H:\EPA_PROG\MOBILE62\Mobile6\Run\96PdxSip\97episod\reg1997.txt 

I/M PROGRAM : 1 1993 2050 2 T/O ASM 2525 PHASE-IN 

I/M MODEL YEARS : 1 1968 2050 

I/M VEHICLES : 1 22222 11111111 1 

I/M STRINGENCY : 1 34.0 

I/M COMPLIANCE : 1 93.0 

I/M WAIVER RATES : 1 2.0 4.0 

I/M GRACE PERIOD : 1 1 

I/M PROGRAM : 2 1993 2050 2 T/O 2500/IDLE 

I/M MODEL YEARS : 2 1968 2050 

I/M VEHICLES : 2 11111 22222222 2 

I/M STRINGENCY : 2 34.0 

I/M COMPLIANCE : 2 93.0 

I/M WAIVER RATES : 2 2.0 4.0 

I/M GRACE PERIOD : 2 1 

******************** Scenario Section ***************************** 

SCENARIO RECORD : Summer Fleet-Average Emission 

CALENDAR YEAR : 1997 

EVALUATION MONTH : 7 

* Hourly temp will be varied from 50-101 F. To create temperature profile used by SMOKE 

MIN/MAX TEMP : 50 50 

111
ABSOLUTE HUMIDITY : 50.24 

PARTICULATE EF : PMGZML.CSV PMGDR1.CSV PMGDR2.CSV PMDZML.CSV PMDDR1.CSV 

PMDDR2.CSV 

PARTICLE SIZE : 10.0 

DIESEL SULFUR : 260 

* Filename: WaNoIM97 -- 1997 Washington No I/M counties 

* (for the remainder of the domain) run with M6.2 

* This input generates the summer fleet-average VOC, CO, NOx, SOx and PM10 emissions 

from CY1997 for all Washington Non I/M counties in themodeling domain using Washington 

1997 reg data (reg1997) because it is the registration developed for that year (vs using the 1999 

distribution). 

******************* Header Section ************************ 

MOBILE6 INPUT FILE 

PARTICULATES : 

SPREADSHEET : 

DATABASE OUTPUT : 

WITH FIELDNAMES : 

AGGREGATED OUTPUT : 

RUN DATA 

******************* Run Section *************************** 

NO REFUELING : 

FUEL RVP : 8.5 

* enter the appropriate registration distribution filename for the county being modeled. 

REG DIST : H:\EPA_PROG\MOBILE62\Mobile6\Run\96PdxSip\97episod\reg1997.txt 

******************* Scenario Section ********************** 

SCENARIO RECORD : Summer Fleet-Average Emission 

CALENDAR YEAR : 1997 

EVALUATION MONTH : 7 

* Hourly temp will be varied from 50-101 F. To create temperature profile used by SMOKE 

MIN/MAX TEMP : 50 50 

ABSOLUTE HUMIDITY : 50.24 

PARTICULATE EF : PMGZML.CSV PMGDR1.CSV PMGDR2.CSV PMDZML.CSV PMDDR1.CSV 

PMDDR2.CSV 

PARTICLE SIZE : 10.0 

DIESEL SULFUR : 350.0 

* Filename: PDXIM97 -- Tricounty Portland Ozone I/M run with M6 

* This input generates the summer fleet-average VOC, CO, SOx and NOx emissions from 

CY1997 for Tri-County area using Tri-county average 1996 registration from the reg data we 

used for the 1996 EI because this data is closer in time to the 97 modeling year and applying the 

112
reg data to the LDV and LDT and using the Wa ECOLOGY 1999 vehicle registration for vehicle 

classes 6-16. 

******************* Header Section ************************ 

MOBILE6 INPUT FILE 

PARTICULATES : 

SPREADSHEET : 

DATABASE OUTPUT : 

WITH FIELDNAMES : 

AGGREGATED OUTPUT : 

RUN DATA 

******************* Run Section *************************** 

NO REFUELING : 

FUEL RVP : 7.8 

* enter the appropriate registration distribution filename for the county being modeled. 

REG DIST : h:\EPA_PROG\MOBILE62\Mobile6\Run\96PdxSip\97episod\RegTRI97.d 

* The Metro area has 2 levels of tests (during 1997) so there needs to be 2 I/M program entries 

* 1981-1995 Enhanced test, 1975-1980 Basic test, only the LD vehicles get tested. 

* 1981-1995 Enhanced (Bar 31) Gary Beyer says this test (2525/5015) models real world better than IM240 

I/M PROGRAM : 1 1975 2020 2 T/O ASM 2525/5015 FINAL 

I/M MODEL YEARS : 1 1981 2020 

I/M VEHICLES : 1 22222 11111111 1 

I/M STRINGENCY : 1 37.4 

I/M COMPLIANCE : 1 90.0 

I/M WAIVER RATES : 1 0.0 0.0 

I/M CUTPOINTS : 1 ORCUTPT.d 

I/M GRACE PERIOD : 1 2 

* 1975-1980 Basic 

* According to VIP policy 201 "all 1975-1980 gasoline vehicles are subject to the Basic test." 

I/M PROGRAM : 2 1975 2020 2 T/O 2500/IDLE 

I/M MODEL YEARS : 2 1975 1980 

I/M VEHICLES : 2 22222 22222222 2 

I/M STRINGENCY : 2 37.4 

I/M COMPLIANCE : 2 90.0 

I/M WAIVER RATES : 2 0.0 0.0 

ANTI-TAMP PROG : 

75 75 80 22222 22222222 1 12 090. 22212221 

******************* Scenario Section ********************** 

* A separate scenario must be written for each calendar 

* year to be analyzed. 

SCENARIO RECORD : Summer Fleet-Average Emission 

CALENDAR YEAR : 1997 

EVALUATION MONTH : 7 

113
* Hourly temp will be varied from 50-101 F. To create temperature profile used by SMOKE 

* perl script will create a constant temp (min 61 max 61) throughout the range. 

MIN/MAX TEMP : 50 50 

ABSOLUTE HUMIDITY : 50.24 

PARTICULATE EF : PMGZML.CSV PMGDR1.CSV PMGDR2.CSV PMDZML.CSV PMDDR1.CSV 

PMDDR2.CSV 

PARTICLE SIZE : 10.0 

DIESEL SULFUR : 260 

* Filename: ORNoIM97 -- 1997 Oregon No I/M counties 

For the remainder of the domain run with M6.2 

This input generates the summer fleet-average VOC, CO, NOx, SOx and PM10 emissions from 

CY1997 for all Oregon Non I/M counties in the modeling domain using the 1996 Oregon LDV 

and LDT vehicle class registration from the 1996 EI model year end count we received from the 

DMV and Wa all other registration. 

******************* Header Section ************************ 

MOBILE6 INPUT FILE 

PARTICULATES : 

SPREADSHEET : 

DATABASE OUTPUT : 

WITH FIELDNAMES : 

AGGREGATED OUTPUT : 

RUN DATA 

******************* Run Section *************************** 

NO REFUELING : 

FUEL RVP : 9.0 

* enter the appropriate registration distribution filename for the county being modeled. 

REG DIST : H:\EPA_PROG\MOBILE62\Mobile6\Run\96PdxSip\97episod\regOR97.d 

******************* Scenario Section *************************** 

SCENARIO RECORD : Summer Fleet-Average Emission 

CALENDAR YEAR : 1997 

EVALUATION MONTH : 7 

* Hourly temp will be varied from 50-101 F. To create temperature profile used by SMOKE 

MIN/MAX TEMP : 50 50 

ABSOLUTE HUMIDITY : 50.24 

PARTICULATE EF : PMGZML.CSV PMGDR1.CSV PMGDR2.CSV PMDZML.CSV PMDDR1.CSV 

PMDDR2.CSV 

PARTICLE SIZE : 10.0 

DIESEL SULFUR : 280 

114
1998 Episode 

* Filename: ClrkIM98 -- Clark County I/M run with M6 

* This input generates the summer fleet-average VOC, CO, SOx and NOx emissions from 

CY1998 for Clark County Washington using Washington 1999 registration data. 

******************* Header Section ************************ 

MOBILE6 INPUT FILE 

PARTICULATES : 

SPREADSHEET : 

DATABASE OUTPUT : 

WITH FIELDNAMES : 

AGGREGATED OUTPUT : 

*REPORT FILE : 

RUN DATA 

******************* Run Section *************************** 

NO REFUELING : 

FUEL RVP : 7.8 

* enter the appropriate registration distribution filename for the county being modeled. 

REG DIST : D:\EPA_PROG\MOBILE62\Mobile6N\Run\96PdxSip\reg1999.txt 

I/M PROGRAM : 1 1993 2050 2 T/O ASM 2525 PHASE-IN 

I/M MODEL YEARS : 1 1968 2050 

I/M VEHICLES : 1 22222 11111111 1 

I/M STRINGENCY : 1 36.0 

I/M COMPLIANCE : 1 93.0 

I/M WAIVER RATES : 1 4.0 7.0 

I/M GRACE PERIOD : 1 1 

I/M PROGRAM : 2 1998 2050 2 T/O GC 

I/M MODEL YEARS : 2 1968 2050 

I/M VEHICLES : 2 22222 22222222 2 

I/M STRINGENCY : 2 36.0 

I/M COMPLIANCE : 2 93.0 

I/M WAIVER RATES : 2 4.0 7.0 

I/M GRACE PERIOD : 2 1 

I/M PROGRAM : 3 1993 2050 2 T/O 2500/IDLE 

I/M MODEL YEARS : 3 1968 2050 

I/M VEHICLES : 3 11111 22222222 2 

I/M STRINGENCY : 3 36.0 

I/M COMPLIANCE : 3 93.0 

I/M WAIVER RATES : 3 4.0 7.0 

I/M GRACE PERIOD : 3 1 

******************** Scenario Section ***************************** 

SCENARIO RECORD : Summer Fleet-Average Emission 

CALENDAR YEAR : 1998 

EVALUATION MONTH : 7 

115
* Hourly temp will be varied from 50-101 F. To create temperature profile used by SMOKE 

MIN/MAX TEMP : 50 50 

ABSOLUTE HUMIDITY : 64.01 

PARTICULATE EF : PMGZML.CSV PMGDR1.CSV PMGDR2.CSV PMDZML.CSV PMDDR1.CSV 

PMDDR2.CSV 

PARTICLE SIZE : 10.0 

DIESEL SULFUR : 260 

* Filename: WaNoIM98 -- 1998 Washington No I/M counties 

For the remainder of the domain run with M6.2 

This input generates the summer fleet-average VOC, CO, NOx, SOx and PM10 

emissions from CY1998 for all Washington Non I/M counties in the modeling domain using 

Washington 1999 reg data (Sally thinks that is better than the 1998). 

******************* Header Section ************************ 

MOBILE6 INPUT FILE 

PARTICULATES : 

SPREADSHEET : 

DATABASE OUTPUT : 

WITH FIELDNAMES : 

AGGREGATED OUTPUT : 

RUN DATA 

******************* Run Section *************************** 

NO REFUELING : 

FUEL RVP : 8.5 

* enter the appropriate registration distribution filename for the county being modeled. 

REG DIST : D:\EPA_PROG\MOBILE62\Mobile6N\Run\96PdxSip\reg1999.txt 

******************* Scenario Section ********************** 

SCENARIO RECORD : Summer Fleet-Average Emission 

CALENDAR YEAR : 1998 

EVALUATION MONTH : 7 

* Hourly temp will be varied from 50-101 F. To create temperature profile used by SMOKE 

MIN/MAX TEMP : 50 50 

ABSOLUTE HUMIDITY : 64.01 

PARTICULATE EF : PMGZML.CSV PMGDR1.CSV PMGDR2.CSV PMDZML.CSV PMDDR1.CSV 

PMDDR2.CSV 

PARTICLE SIZE : 10.0 

DIESEL SULFUR : 350.0 

116
* Filename: PDXIM98 -- Tricounty Portland Ozone I/M run with M6 

* This input generates the summer fleet-average VOC, CO, SOx and NOx emissions from 

CY1998 for Tri-County area using Tri-county average 2002 registration from Jeff's query of the 

DMV data (no gas/diesel distinction) and applying the reg data to the LDV and LDT and using 

the Wa ECOLOGY 1999 vehicle registration for vehicle classes 6-16. 

******************* Header Section ************************ 

MOBILE6 INPUT FILE 

PARTICULATES : 

SPREADSHEET : 

DATABASE OUTPUT : 

WITH FIELDNAMES : 

AGGREGATED OUTPUT : 

RUN DATA 

******************* Run Section *************************** 

NO REFUELING : 

FUEL RVP : 7.8 

* enter the appropriate registration distribution filename for the county being modeled. 

REG DIST : D:\EPA_PROG\MOBILE62\Mobile6N\Run\96PdxSip\IM98OR.d 

* The Metro area has three levels of tests so there needs to be 3 I/M program entries 

* 1996 to present gets OBD, 1981-1995 Enhanced test, 1975-1980 Basic test 

* only the LD vehicles get tested 

* 1996+ OBD exhaust benefits 

I/M PROGRAM : 1 1975 2020 2 T/O OBD I/M 

I/M MODEL YEARS : 1 1996 2020 

I/M VEHICLES : 1 22222 11111111 1 

I/M STRINGENCY : 1 37.4 

I/M COMPLIANCE : 1 90.0 

I/M WAIVER RATES : 1 0.0 0.0 

I/M GRACE PERIOD : 1 2 

* 1996+ OBD evaporative benefits 

I/M PROGRAM : 2 1975 2020 2 T/O EVAP OBD 

I/M MODEL YEARS : 2 1996 2020 

I/M VEHICLES : 2 22222 11111111 1 

I/M STRINGENCY : 2 37.4 

I/M COMPLIANCE : 2 90.0 

I/M WAIVER RATES : 2 0.0 0.0 

I/M GRACE PERIOD : 2 2 

* 1981-1995 Enhanced (Bar 31) Gary Beyer says this test (2525/5015) models real world better than IM240 

I/M PROGRAM : 3 1975 2020 2 T/O ASM 2525/5015 FINAL 

I/M MODEL YEARS : 3 1981 1995 

I/M VEHICLES : 3 22222 11111111 1 

I/M STRINGENCY : 3 37.4 

I/M COMPLIANCE : 3 90.0 

I/M WAIVER RATES : 3 0.0 0.0 

I/M CUTPOINTS : 3 ORCUTPT.d 

117
* 1975-1980 Basic 

* According to VIP policy 201 "all 1975-1980 gasoline vehicles are subject to the Basic test." 

I/M PROGRAM : 4 1975 2020 2 T/O 2500/IDLE 

I/M MODEL YEARS : 4 1975 1980 

I/M VEHICLES : 4 22222 22222222 2 

I/M STRINGENCY : 4 37.4 

I/M COMPLIANCE : 4 90.0 

I/M WAIVER RATES : 4 0.0 0.0 

ANTI-TAMP PROG : 

75 75 80 22222 22222222 1 12 090. 22212221 

******************* Scenario Section ********************** 

* A separate scenario must be written for each calendar year to be analyzed. 

SCENARIO RECORD : Summer Fleet-Average Emission 

CALENDAR YEAR : 1998 

EVALUATION MONTH : 7 

* Hourly temp will be varied from 50-101 F. To create temperature profile used by SMOKE 

* perl script will create a constant temp (min 61 max 61) throughout the range. 

MIN/MAX TEMP : 50 50 

ABSOLUTE HUMIDITY : 64.01 

PARTICULATE EF : PMGZML.CSV PMGDR1.CSV PMGDR2.CSV PMDZML.CSV PMDDR1.CSV 

PMDDR2.CSV 

PARTICLE SIZE : 10.0 

DIESEL SULFUR : 260 

* Filename: ORNoIM98 -- 1998 Oregon No I/M counties 

 For the remainder of the domain run with M6.2 

This input generates the summer fleet-average VOC, CO, NOx, SOx and PM10 

emissions from CY1998 for all Oregon Non I/M counties in the modeling domain using Oregon 

LDV and LDT vehicle class registration and Wa all other registration. 

******************* Header Section ************************ 

MOBILE6 INPUT FILE 

PARTICULATES : 

SPREADSHEET : 

DATABASE OUTPUT : 

WITH FIELDNAMES : 

AGGREGATED OUTPUT : 

RUN DATA 

******************* Run Section *************************** 

NO REFUELING : 

FUEL RVP : 9.0 

* enter the appropriate registration distribution filename for the county being modeled. 

REG DIST : D:\EPA_PROG\MOBILE62\Mobile6N\Run\96PdxSip\NoIM98OR.d 

******************* Scenario Section *************************** 

118
SCENARIO RECORD : Summer Fleet-Average Emission 

CALENDAR YEAR : 1998 

EVALUATION MONTH : 7 

* Hourly temp will be varied from 50-101 F. To create temperature profile used by SMOKE 

MIN/MAX TEMP : 50 50 

ABSOLUTE HUMIDITY : 64.01 

PARTICULATE EF : PMGZML.CSV PMGDR1.CSV PMGDR2.CSV PMDZML.CSV PMDDR1.CSV 

PMDDR2.CSV 

PARTICLE SIZE : 10.0 

DIESEL SULFUR : 280 

* Filename: Q15Clrk -- Clark County I/M run with M6 

* This input generates the summer fleet-average emissions from CY2015 

* for Clark County Washington using Washington 2004 registration data. 

* This is the file run by DEQ for the CMAQ modeling of the future episode. 

******************* Header Section ************************ 

MOBILE6 INPUT FILE 

PARTICULATES : 

SPREADSHEET : 

DATABASE OUTPUT : 

WITH FIELDNAMES : 

AGGREGATED OUTPUT : 

RUN DATA 

******************* Run Section *************************** 

EXPAND EVAPORATIVE : 

*STAGE II REFUELING : 92 2 80. 80. 

FUEL RVP : 7.8 

* enter the appropriate registration distribution filename for the county being modeled. 

REG DIST : H:\EPA_PROG\MOBILE62\Mobile6\Run\Regdist\WaReg\reg2004.txt 

* There were not enough programs to define the 1) HDGV2b/3 EVAP OBD & GC program 

* anticipated to begin in 2008 and 2) HDGV4+ GC program that began in 2002. 

* HDGV gas cap added to program 2 to at least get some of the HD GC test 

* Received from W.Strange 10/21/2004 after consultation with his management. 

I/M PROGRAM : 1 1993 2050 2 T/O ASM 2525 PHASE-IN 

I/M MODEL YEARS : 1 1968 1995 

I/M VEHICLES : 1 22222 11111111 1 

I/M STRINGENCY : 1 42.4 

I/M COMPLIANCE : 1 91.0 

I/M WAIVER RATES : 1 4.9 15.8 

I/M EXEMPTION AGE : 1 25 

119
I/M GRACE PERIOD : 1 5 

I/M PROGRAM : 2 1998 2050 2 T/O GC 

I/M MODEL YEARS : 2 1968 1995 

I/M VEHICLES : 2 22222 22222222 2 

I/M COMPLIANCE : 2 91.0 

I/M WAIVER RATES : 2 4.9 15.8 

I/M EXEMPTION AGE : 2 25 

I/M GRACE PERIOD : 2 5 

I/M PROGRAM : 3 1993 2050 2 T/O OBD I/M 

I/M MODEL YEARS : 3 1996 2050 

I/M VEHICLES : 3 22222 11111111 1 

I/M STRINGENCY : 3 42.4 

I/M COMPLIANCE : 3 91.0 

I/M WAIVER RATES : 3 4.9 5.3 

I/M EXEMPTION AGE : 3 25 

I/M GRACE PERIOD : 3 5 

I/M PROGRAM : 4 2002 2050 2 T/O EVAP OBD & GC 

I/M MODEL YEARS : 4 1996 2050 

I/M VEHICLES : 4 22222 11111111 1 

I/M COMPLIANCE : 4 91.0 

I/M WAIVER RATES : 4 4.9 5.3 

I/M EXEMPTION AGE : 4 25 

I/M GRACE PERIOD : 4 5 

I/M PROGRAM : 5 1993 2050 2 T/O 2500/IDLE 

I/M MODEL YEARS : 5 1968 2050 

I/M VEHICLES : 5 11111 11222222 2 

I/M STRINGENCY : 5 42.4 

I/M COMPLIANCE : 5 91.0 

I/M WAIVER RATES : 5 4.9 8.3 

I/M EXEMPTION AGE : 5 25 

I/M GRACE PERIOD : 5 5 

I/M PROGRAM : 6 1993 2050 2 T/O 2500/IDLE 

I/M MODEL YEARS : 6 1968 2007 

I/M VEHICLES : 6 11111 22111111 1 

I/M STRINGENCY : 6 42.4 

I/M COMPLIANCE : 6 91.0 

I/M WAIVER RATES : 6 4.9 8.3 

I/M EXEMPTION AGE : 6 25 

I/M GRACE PERIOD : 6 5 

I/M PROGRAM : 7 1993 2050 2 T/O OBD I/M 

I/M MODEL YEARS : 7 2008 2050 

I/M VEHICLES : 7 11111 22111111 1 

I/M STRINGENCY : 7 42.4 

I/M COMPLIANCE : 7 91.0 

I/M WAIVER RATES : 7 4.9 5.3 

I/M EXEMPTION AGE : 7 25 

I/M GRACE PERIOD : 7 5 

******************** Scenario Section ***************************** 

120
SCENARIO RECORD : Summer Fleet-Average Emission 

CALENDAR YEAR : 2015 

EVALUATION MONTH : 7 

* Hourly temp will be varied from 50-102 F. To create temperature profile used by SMOKE 

MIN/MAX TEMP : 50 50 

ABSOLUTE HUMIDITY : 50.24 

PARTICULATE EF : PMGZML.CSV PMGDR1.CSV PMGDR2.CSV PMDZML.CSV PMDDR1.CSV 

PMDDR2.CSV 

PARTICLE SIZE : 10.0 

DIESEL SULFUR : 15 

* Filename: Q15PDXIM-- 2015 Tri County I/M 

This input generates the summer fleet-average VOC, CO and NOx, PM10 emissions from 

CY2015 for Multnomah, Washington and Clackamas Counties using the tri-county LDGV and 

LDDV registration and appropriate extended registration from WA for HDV. This is the file run 

by DEQ for the CMAQ modeling of the future episode. This file calculates the refueling 

emission as being controlled by the canisters on-board the vehicles. There is no longer any stage 

II vapor recovery systems in place at the gas stations. 

******************* Header Section ************************ 

MOBILE6 INPUT FILE 

PARTICULATES : 

SPREADSHEET : 

DATABASE OUTPUT : 

WITH FIELDNAMES : 

AGGREGATED OUTPUT : 

RUN DATA 

******************* Run Section *************************** 

EXPAND EVAPORATIVE : 

*STAGE II REFUELING : 92 2 80. 80. 

FUEL RVP : 7.8 

* enter the appropriate registration distribution filename path for the county being modeled. 

REG DIST : R02PDX2.d 

* 2 I/M program entries 

* 1996 to CY - 2 gets OBD, 1975-1995 Basic test 

* 1996+ OBD exhaust benefits 

I/M PROGRAM : 1 1975 2020 2 T/O OBD I/M 

I/M MODEL YEARS : 1 1996 2020 

I/M VEHICLES : 1 22222 11111111 1 

I/M STRINGENCY : 1 37.4 

I/M COMPLIANCE : 1 90.0 

I/M WAIVER RATES : 1 0.0 0.0 

I/M GRACE PERIOD : 1 4 

121
* 1996+ OBD evaporative benefits 

I/M PROGRAM : 2 1975 2020 2 T/O EVAP OBD 

I/M MODEL YEARS : 2 1996 2020 

I/M VEHICLES : 2 22222 11111111 1 

I/M STRINGENCY : 2 37.4 

I/M COMPLIANCE : 2 90.0 

I/M WAIVER RATES : 2 0.0 0.0 

I/M GRACE PERIOD : 2 4 

* 1975-1980 Basic - light duty gas vehicle basic testing 

I/M PROGRAM : 3 1975 2025 2 T/O 2500/IDLE 

I/M MODEL YEARS : 3 1975 1995 

I/M VEHICLES : 3 22222 11111111 1 

I/M STRINGENCY : 3 37.4 

I/M COMPLIANCE : 3 90.0 

I/M WAIVER RATES : 3 0.0 0.0 

* 1975-1980 Basic - to correctly model the HDGV basic testing 

I/M PROGRAM : 4 1975 2025 2 T/O 2500/IDLE 

I/M MODEL YEARS : 4 1975 2025 

I/M VEHICLES : 4 11111 22222222 2 

I/M STRINGENCY : 4 37.4 

I/M COMPLIANCE : 4 90.0 

I/M WAIVER RATES : 4 0.0 0.0 

ANTI-TAMP PROG : 

75 75 80 22222 22222222 1 12 090. 22212222 

******************* Scenario Section ********************** 

* A separate scenario must be written for each calendar 

* year to be analyzed. 

****************************************************************************************** 

SCENARIO RECORD : Summer Fleet-Average Emission 

CALENDAR YEAR : 2015 

EVALUATION MONTH : 7 

* Hourly temp will be varied from 50-100 F. To create temperature profile used by SMOKE 

MIN/MAX TEMP : 50 50 

ABSOLUTE HUMIDITY : 50.24 

PARTICULATE EF : PMGZML.CSV PMGDR1.CSV PMGDR2.CSV PMDZML.CSV PMDDR1.CSV 

PMDDR2.CSV 

PARTICLE SIZE : 10.0 

DIESEL SULFUR : 15 

* Filename: Q15PXNIM-- 2015 Tri County No I/M 

 This input generates the summer fleet-average VOC, CO and NOx, PM10 and HAPS emissions 

from CY2015 for Multnomah, Washington and Clackamas Counties using the tri-county LDGV 

and LDDV registration and appropriate extended registration from WA for HDV. This is the file 

run by DEQ for the CMAQ modeling of the future episode. This file calculates the refueling 

emission as being controlled by the canisters on-board the vehicles. 

122
There is no longer any stage II vapor recovery systems in place at the gas stations. 

******************* Header Section ************************ 

MOBILE6 INPUT FILE 

PARTICULATES : 

SPREADSHEET : 

DATABASE OUTPUT : 

WITH FIELDNAMES : 

AGGREGATED OUTPUT : 

RUN DATA 

******************* Run Section *************************** 

EXPAND EVAPORATIVE : 

*STAGE II REFUELING : 92 2 80. 80. 

FUEL RVP : 7.8 

* enter the appropriate registration distribution filename path for the county being modeled. 

REG DIST : R02PDX2.d 

******************* Scenario Section ********************** 

* A separate scenario must be written for each calendar 

* year to be analyzed. 

****************************************************************************************** 

SCENARIO RECORD : Summer Fleet-Average Emission 

CALENDAR YEAR : 2015 

EVALUATION MONTH : 7 

* Hourly temp will be varied from 50-100 F. To create temperature profile used by SMOKE 

MIN/MAX TEMP : 50 50 

ABSOLUTE HUMIDITY : 50.24 

PARTICULATE EF : PMGZML.CSV PMGDR1.CSV PMGDR2.CSV PMDZML.CSV PMDDR1.CSV 

PMDDR2.CSV 

PARTICLE SIZE : 10.0 

DIESEL SULFUR : 15 

* Filename: WaNoIM15 -- 2015 Washington No I/M counties 

(for the remainder of the domain) run with M6.2 

This input generates the summer fleet-average VOC, CO, NOx, SOx and PM10 emissions from 

CY2015 for all Washington Non I/M counties in the modeling domain using latest Washington 

2004 reg data. This is the file run by DEQ for the CMAQ modeling of the future episode. 

******************* Header Section ************************ 

MOBILE6 INPUT FILE 

PARTICULATES : 

SPREADSHEET : 

DATABASE OUTPUT : 

WITH FIELDNAMES : 

AGGREGATED OUTPUT : 

123
RUN DATA 

******************* Run Section *************************** 

EXPAND EVAPORATIVE : 

*STAGE II REFUELING : 92 2 80. 80. 

FUEL RVP : 8.5 

* enter the appropriate registration distribution filename for the county being modeled. 

REG DIST : H:\EPA_PROG\MOBILE62\Mobile6\Run\Regdist\WaReg\reg2004.txt 

******************* Scenario Section ********************** 

SCENARIO RECORD : Summer Fleet-Average Emission 

CALENDAR YEAR : 2015 

EVALUATION MONTH : 7 

* Hourly temp will be varied from 50-100 F. To create temperature profile used by SMOKE 

MIN/MAX TEMP : 50 50 

ABSOLUTE HUMIDITY : 50.24 

PARTICULATE EF : PMGZML.CSV PMGDR1.CSV PMGDR2.CSV PMDZML.CSV PMDDR1.CSV 

PMDDR2.CSV 

PARTICLE SIZE : 10.0 

DIESEL SULFUR : 15 

124
125

Appendix D: Acronyms 

BELD3 Biogenic Emissions Landcover Database - version 3 

BEIS3 Biogenic Emissions Inventory System – version 3 

CAA Clean Air Act 

CMAQ Community Multi-scale Air Quality 

CCTM CMAQ Chemical Transport Model 

Ecology Washington State Department of Ecology 

EKMA Empirical Kinetics Modeling Approach 

EPA Environmental Protection Agency 

GDAS Global Data Assimilation System 

GEOS Goddard Earth Observing System 

ICTC Intercontinental Transport and Chemical Transformation 

KF Kain-Fritsch cumulus scheme 

LSM Land Surface Model 

NCEP National Center for Environmental Prediction 

NOx Oxides of Nitrogen 

MCIP Meteorology-Chemistry Interface processor 

MEBI Modified Euler Backward Interactive 

MM5 Mesoscale Meteorological model Version 5 

MRF Medium Range Forecast 

NAAQS National Ambient Air Quality Standards 

NWRTC Northwest Regional Technical Center 

PBL Planetary Boundary Layer 

SAPRC State Air Pollution Research Center chemical mechanisms 

SIP State Implementation Plan 

SMOKE Sparse Matrix Operator Kernel Emissions Modeling System 

SOx Oxides of Sulfur 

SWCAA Southwest Clean Air Agency 

TV Title V 

VOC Volatile Organic Compound