Joshua Fu, Yun-Fat Lam* and Yang Gao University of Tennessee

1. The effects of Climate Change to the Future Air Quality in United States Joshua Fu, Yun-Fat Lam* and Yang Gao University of Tennessee Daniel Jacob , Loretta Mickley and Shiliang Wu Harvard University Oct 20, 2009

2. GLOBAL CHANGE AND AIR POLLUTION (GCAP) Joshua Fu , Yun-Fat Lam,University of Tennessee Daniel Jacob (PI), Loretta Mickley,Harvard University John Seinfeld,California Institute of Technology David Streets,Argonne National Lab David Rind,GISS/NASA

3. GCAP: How will global change affect U.S. air quality UT SOURCE: GCAP group

4. July global mean temperature 2045-2052 +2o C Temp change { 1995-2002 Timeline 1950 spin-up (ocean adjusts) 2000 increasing A1 greenhouse gas 2050 Effect of Global Warming in GISS General Circulation Model Goddard Institute for Space Studies GCM: 9 layers, 4ox5o horizontal grid, CO2 + other greenhouse gases increased yearly from 2000 to 2050. Carbon Monoxide: CO source: present-day anthropogenic emissions sink: CO + present-day OH fields Black Carbon: BC source: present-day anthropogenic emissions sink: rainout spin up Mickley et al., 2004 SOURCE: GCAP group

5. 2045-2052 Northeast U.S. CO tracer summer 1995-2002 Effect of Climate Change on Regional Stagnation GISS GCM 2’ simulations for 2050 vs. present-day climate using pollution tracers with constant emissions Mid-latitudes cyclones tracking across southern Canada are the main drivers of northern U.S. ventilation Pollution episodes double in duration in 2050 climate due to decreasing frequency of cyclones ventilating the eastern U.S; this decrease is an expected consequence of greenhouse warming. Mickley et al. [GRL 2004] SOURCE: GCAP group

6. 1000 cyclones 500 100 anticyclones 1980 1950 Climatological Fact DECREASE IN FREQUENCY OF MID-LATITUDE CYCLONES OVER PAST 50 YEARS Annual number of surface cyclones and anticylones over North America Agee [1991] Cyclone frequency at 30o-60oN McCabe et al. [2001] SOURCE: GCAP group

7. Atmospheric component Sea Ice component Land surface model component Ocean component Global model vs. Regional Model Global Model Regional Model Climate Missing aerosol feed back Air Quality, Heat waves, Flooding, Drought, Human Health Direct affect solar radiation Two-ways coupled climate and chemistry One-way coupled climate and chemistry

8. Significant of Regional Model • Resolution : down to 1 x 1 km • Taking advantages of detail geographical information in meteorology modeling, as well as highly reliable emission inventories for ozone and aerosol modeling • All the equations in regional model are designed to use in fine resolution conditions • Scalability issue in global model • Regional/urban climate and air quality conditions can be simulated to provide information for local and regional planning • It has better implication in model outputs

9. Development of downscaling approach • Analysis of 2000-2050 trends in air pollution meteorology • Development of GISS/GEOS-Chem interface • Development of GISS/MM5 interface • Development of future emission inventories for carbonaceous aerosols • Application of GISS/GEOS-Chem to 2000-2050 trends in ozone and PM (IPCC A1B scenario) • Statistical projection of 2000-2050 ozone trends

10. Objective • Investigate the future air quality in United States for year 2050 using regional air quality model, CMAQ & MM5 • Study the effect of global warming in regional scale for both climate and air quality • Examine the effect of change of anthropogenic emissions • Determine the emission reduction offsets required to maintain NAAQS

11. Model Configurations • Models: • Global Models • GISS-GCM III (GISS/NASA) • GEOS-Chem IV (HARVARD UNIVERSITY) • Regional Models • MM5 and WRF (NCAR) • CMAQ 4.6 (EPA and others) • Interface Program Development and Regional Modeling (UT) • GISS2MM5 => MM5 (UT) • GEOS-Chem => CMAQ (UT)

12. Global Model Configurations Climate Model Chemistry Model GISS general circulation model III • Global climate model • Provide initial guess values for MM5 (Both current and future climate conditions - e.g. 2000 and 2050) • 4° x 5° horizontal resolution • 30 vertical sigma/pressure layers GEOS-Chem IV • Global chemistry model • Provide initial and boundary conditions for CMAQ • 2° x 2.5° horizontal resolution • 28 vertical sigma/pressure layers • Take into account of volcanic events, wild fire, lightning and dust storm across the globe

13. Regional Model Configurations Climate Model Chemistry Model MM5 • Regional climate model • Terrain followed sigma coordination • Resolution: 108km and nest down to 36km (can be down to 1 km) • 43 vertical sigma/pressure layers • Preprocessor: TERRAIN, REGRID, LITTLE_R, INTERPF and NESTDOWN CMAQ 4.6 • 14 layers (from the MM5 sigma levels) • 36 km horizontal resolution (in this study) • ICON and BCON from GEOS-Chem from 3 hrs to one hour average • GISS/MM5 meteorological Inputs • Input emission is compatible with 2001 EPA National Emission Inventory

14. Year 2000 Year 2050 Example Results of MM5 Outputs from GISS GISS surface wind and temperature Inputs GISS • Source:L. Mickley (Harvard) MM5 MM5 108 km - CONUS 36 km - CONUS

15. GISS Vs. MM5

16. MidN NE SE GISS Vs. MM5 (JJAS) MAX & AVG Temperature Average Temperature (K)

17. GISS Vs. MM5 (JJAS) • Temperature RMSE is below 0.4 K. And the mean bias is close to 0.1 K << 0.5 (benchmark) • Wind speed RMSE is less than 0.2 m/s << 2 m/s (benchmark). For the mean bias, the value is 0.1 m/s • Wind direction RMSE is less than 20° and mean bias is less than 1 ° << 10 °

18. 2000 climate with 2000 emission 2050 climate with 2000 emission Climate/Emission Contributions 2000 climate with 2050 emission 2050 climate with 2050 emission CMAQ Simulations Scenarios • Study period: June 1 to September 1 (Ozone season) Emission Projection 2000 NO2 2050 NO2 IPCC NOx Emission Scenario X

19. Maximum Ozone Concentration warmer 2000climate-2000emi 2050climate-2000emi 2000climate-2050emi 2050climate-2050emi Fu et al. 2008 Emission has more effect than climate change on pollution events

20. CMAQ Simulations – Output (JJAS) MAXIMUM OZONE AVERAGE OZONE

21. Source: Harvard University

22. GEOS-Chem Vs. CMAQ (JJAS)

23. GEOS-Chem Vs. CMAQ (JJAS)

24. GEOS-Chem Vs. CMAQ (JJAS) – MidN Large difference in temperature Small difference in wind speed The CMAQ’s trend is similar as GEOS-Chem’s trend (Temperature dominated case)

25. GEOS-Chem Vs. CMAQ (JJAS) - NE Small difference in temperature Small difference in wind speed The CMAQ’s trend is not similar as GEOS-Chem’s trend (Emission domination case)

26. GEOS-Chem Vs. CMAQ (JJAS) – SE Large difference in temperature Large difference in wind speed The CMAQ’s trend is not similar as GEOS-Chem’s trend (Cloud dominated case) ?? Why different from NE ??

27. Remarks • Global downscaling of GISS and GEOS-Chem have successfully performed with high confidence. • The ozone trend (2050 – 2000) of GEOS-Chem and CMAQ are found to be quite difference, where GEOS-Chem is much more temperature driven (may due to the coarse resolution of meteorological data) • In GEOS-Chem, climate change is a stronger factor than emission change for MidN and NE, but not showing in SE • In CMAQ, only MidN have shown stronge climate change effect. • Overall, the maximum zonal ozone concentration in 2050 is much higher than 2000. However, the probability of getting higher ozone may not higher. The convection and cloud cover have played important role on this issue.

28. THANK YOU!

29. Average Aerosol (PM2.5) Concentration Emission has more effect than climate change on pollution events ? BLACK CARBON SULFATE AEROSOL Climate Effect Emission Effect US US Climate change doesn’t effect South-East ?