1. Determining Alternative Futures - Urban Development Effects on Air Quality Julide Kahyaoglu-Koracin and Darko Koracin May 2007 Zagreb, Croatia

2. Objectives Evaluate the impact of the four alternative futures on air quality in Southwest California Develop a modeling system to integrate projected land use patterns with atmospheric emissions and secondary pollutants, meteorology and dispersion, and transportation Provide an assessment of the likelihood that San Diego County will violate various Federal and California Standards

3. Framework for the assessment of air quality using an alternative futures methodology (Mouat et al., 2004)

4. Species of interest Primary Pollutants: CO NO x SO 2 PM 2.5, PM 10 VOCs Secondary Pollutants O 3 PM 2.5

5. Current non-attainment designations for San Diego County Pollutant Averaging TimeFederal Standard California State Standard O3O3 1-hrMaintenance areaNon-attainment O3O3 8-hrNon-attainmentNot applicable PM 10 AnnualAttainmentNon-Attainment PM 2.5 AnnualNon-attainmentNot yet designated

6. Major commuting zones and associated work centers

7. Orange and Los Angeles Counties Riverside County San Diego County (West) San Diego County (NE) San Diego County (SE) Orange and Los Angeles Counties 97%2%1%0% Riverside County25%72%2%1%0% San Diego County (West) 1% 97%1%0% San Diego County (Northeast) 1% 86%12%0% San Diego County (Southeast) 1% 93%4%1% Transportation modeling: Percentage of commuters traveling from home (rows) to work centers (columns)

8. Total NO x Base Case Emissions

9. (Shearer et al., 2004)

10. SpeciesCONO x SO 2 TOG (VOC)PM SourceAreaMobileAreaMobileAreaMobileAreaMobileAreaMobile 20036.921817.142.63220.210.02912.0882.47193.79287.086.06 Coastal Future: 500 k7.251968.833.26233.000.03312.1687.84207.62287.166.99 change0.26151.690.6312.800.0040.085.3713.820.080.93 1,000 k7.502152.463.89247.270.03712.2793.21220.32287.248.04 change0.51335.321.2627.070.0080.1910.7426.530.171.98 Example of emissions estimates (tons/day) for existing conditions and the Coastal Future

11. 2003 Coastal Northern Reg. Low Density Three Centers CO 1817.142152.462165.202145.282144.09 Change 335.32348.06328.14326.95 NO x 220.21247.27249.21247.33247.00 Change 27.0629.0027.1226.79 SO 2 12.0812.27 12.26 Change 0.190.200.19 TOG (VOC) 193.79220.32222.44223.89221.36 Change 26.5328.6530.1027.57 PM 6.068.048.268.388.14 Change 1.982.202.322.08 Mobile source emissions estimates (tons/day) for existing conditions and the Alternative Futures

12. NO x emissions by source category AreaMobile Stationary Biogenic

13. NO x emissions by scenario with 1,000k new residents CoastalNorthern Regional Low Density Three Centers

14. MM5 generated one-hour average temperature, wind, and sea- level pressure for July 10, 2003, 10AM -> CAMx

15. Maximum O 3 for July 10, 2003

16. O 3 difference distributions by scenario for 1,000k new residents CoastalNorthern Regional Low Density Three Centers

17. PM 2.5 difference distribution by scenario for 1,000k new residents CoastalNorthern Regional Low Density Three Centers

18. SimulationsJuly 7July 8July 9July 10July 11 Max O 3 Diff.Max O 3 Diff.Max O 3 Diff.Max O 3 Diff.Max O 3 Diff. Base Case115-132-129-135-121- Coastal Future (1,000k) 128131342136714381287 Northern Future (1,000k) 138231342142131461113312 Regional Low Density Future (1,000k) 150351342142131461113716 Three Centers Futures (1,000k) 139241342141121461113413 Predicted maximum ozone (ppb) values for five simulations and episode days

19. Summary The addition of 500k or 1,000k residents to the study area appears to have a greater overall impact on air quality than does their distribution. Nevertheless the resultant differences in human activity influence air quality. The project developed a modeling system to predict air quality based on changes in land use patterns resulting from development and growth

20. The system coupled land-use predictions with transportation, emissions, meteorology, dispersion, and transportation models. This tool can allow potential users to evaluate and assess other “least likely impacts” stemming from the impacts of future growth. Summary (cont.)

21. The area will continue to be in violation of the annual Federal PM 2.5 and California 1-hour O 3 standards, and is likely to be in violation of the annual California PM 2.5 and Federal 1-hour O 3 standards. Regulators should focus on reducing primary PM 2.5