Overview of GCAP Project October 12, 2007 Harvard University PI: Jacob Co-Is: Byun, Fu, Mickley, Seinfeld, Streets, Rind Also: Wu, Liao, Lam, Li, Yoshitomi, Smith-Downey, Pye, Kim, Lerner, Leibensperger change in climate change in pollutant emissions BC energy emissions change in U.S. air quality Ozone episode, July 2007

GCAP Phase 2: How will global change affect U.S. air quality and mercury deposition rates? Precursor emissions from Streets archive met fields GEOS-CHEM Global chemistry model CMAQ Regional chemistry model GISS general circulation model Spin-up MM5 Mesoscale model archive chemistry archive met fields changing greenhouse gases

Basic blueprint for GCAP project GISS GCM transient climate simulation Compare 2000 and 2050 climate and emissions Archive results GEOS-CHEM global O 3 -PM-Hg simulation MM5 mesoscale dynamics simulation CMAQ regional O 3 -PM- Hg simulation boundary conditions met fields boundary conditions emissions GCAP Phase 2: How will global change affect U.S. air quality and mercury deposition to U.S. ecosystems?

GCAP Phase 1 Publications Streets et al., On the future of carbonaceous aerosol emissions, JGR, Mickley et al., Effects of future climate change on regional air pollution episodes in the United States, GRL, Liao et al., Role of climate change in global predictions of future tropospheric ozone and aerosols, JGR, Rind et al., Effects of resolution and model physics on tracer transports in the NASA Goddard Institute for Space Studies general circulation models, JGR, Wu et al., Why are there large differences between models in global budgets of tropospheric ozone?, JGR, Liao et al., Biogenic secondary organic aerosol over the United States: Comparison of climatological simulations with observations, JGR, Wu et al., Effects of global change on ozone air quality in the United States, submitted, Wu et al., Effect of global change on background ozone in the United States, in progress, Fu et al., MICS-Asia II: Modeling gaseous pollutants and evaluating an advanced modeling system over east Asia, Atmos. Env., 2007 Emissions Model 2’ climate + AQ Model 3 development GCAP debut and evaluation Global change + AQ Regional model results

Interhemispheric gradient in CFC-11 in different GISS GCMs Model 3 has more realistic interhemispheric transport than some of the other models. Rind et al Model 3 obs Model E Trends in carbonaceous aerosol emissions: For anthropogenic BC, all scenarios predict decreases by Streets et al., BC/EnergyOC/Energy Some highlights of Phase 1

Predicted changes in surface sulfate concentrations due solely to climate change, Liao et al Greater precip at high latitudes Weaker Hadley cell Greater OH, H 2 O 2, and ozone concs over urban areas surface ozone surface PM 2.5 Results from GEOS- Chem/CMAQ interface for China, Fu et al. Harvard results: to be shown later today. ppt

New goals for Phase 2: Analyze impact of different climate and emission scenarios on U.S. air quality (e.g., A1, B1, B2, ACCENT). Examine impact of changes in anthropogenic emissions on intercontinental transport to the United States Investigate how global change will affect mercury deposition in U.S. ecosystems.. Improve coupling between global and regional climate models. JJA 1990s temperatures from the GISS-GCM and MM5, mean over 5 summers, Lynn et al.

GCAP Phase 2 flow plan A rgonne G ISS Global Hg emissions Model 3 development + support H arvard GCAP A1, B1, B2ACCENT scenarios C altech Aerosol evaluation and analysis UT enn Regional chemical + Hg simulations UH ouston O 3 + Hg analysis MM5 nudging + stepwise downscaling MM5 STE and tropopause heights Regional Hg emissions ACCENT scenarios Arrows show interaction, not deadlines.

Year 1 – official start date May 07 Argonne: Develop global emission projections for mercury for different IPCC scenarios Harvard/ GISS: Run GISS GCM simulations for IPCC A2, B1, and B2 scenarios Interpret results for on-line pollution tracers Archive output for GEOS-Chem and MM5 Harvard/ Caltech: Run GEOS-Chem ozone-aerosol simulations for 2000 and 2050: ~5-year ensembles, different IPCC scenarios, interpret results Archive output for CMAQ U Tenn/ Harvard/ Caltech: Run CMAQ simulations for each IPCC scenario, interpret results U Houston: Improve GISS-MM5 dynamical interface through stepwise downscaling Investigate the effect of in-domain nudging with GISS met fields in MM5

Year 2 All: Continue and publish work from Year 1 Argonne: Downscale mercury emission projections in the United States for CMAQ Harvard: Run GEOS-Chem mercury simulations for the 2000 and 2050 GCM atmospheres (5-year ensembles) of each IPCC scenario, interpret results. Archive output for CMAQ. UTenn/ Harvard: Run CMAQ mercury simulations for the 2000 and 2050 GCM atmospheres, interpret results U Houston: Investigate and reconcile GISS and MM5 simulations of tropopause height and stratosphere-troposphere exchange

Year 3 All: Continue and publish work from Year 2 Harvard/U Tenn/ Caltech: Run GEOS-Chem using the ACCENT scenarios Downscale chemistry using CMAQ Interpret results

Tasks/ Issues leftover from GCAP phase 1: Harvard: Conduct EOF analyses of ozone regional variability in the United States – on the back burner (Leibensperger) U Tenn: Run CMAQ with 2000 and 2050 climate – ongoing Harvard/ Caltech/ U Tenn: Run ozone and PM simulations for 2050 B1 climate – moved to GCAP phase 2. Other tasks, goals? Understand ozone response to temperature change in Southeast U.S. Analyze trends in cyclone variability and relationship to pollution episodes. Explore correlations of PM 2.5 with met variables for potential future-climate statistical projections (already being done for ozone). Improve GCM-GEOS-chem interface: boundary layer height, vertical diffusion... Compare IPCC near-term emissions trajectories with observed trends.

GCAP Phase 2 flow plan A rgonne G ISS Global Hg emissions Model 3 development + support H arvard GCAP A1, B1, B2ACCENT scenarios C altech Aerosol evaluation and analysis UT enn Regional chemical + Hg simulations UH ouston O 3 + Hg analysis MM5 nudging + stepwise downscaling MM5 STE and tropopause heights Regional Hg emissions ACCENT scenarios

For chemistry, the winner is Garhard Ertl “for pioneering work in surface chemistry, a specialty that... sheds light on the activity... on the surface of ice crystals in the stratosphere.“ NYT For peace, winners are Al Gore and IPCC Nobel Prizes recognize Atmospheric Sciences!