GEOS-CHEM GLOBAL 3-D MODEL OF TROPOSPHERIC CHEMISTRY Assimilated NASA/DAO meteorological observations for o x1 o to 4 o x5 o horizontal resolution, vertical layers Applied to simulations of O 3, aerosols, precursors, other species in different regions of the world 120 chemical species to describe tropospheric O 3 -NO x -hydrocarbon chemistry; aerosol effects on chemistry, radiation

MODEL EVALUATION OF TRANSATLANTIC TRANSPORT OF OZONE AND PRECURSORS: [Li et al., 2001]

MODEL EVALUATION WITH 1997 OZONESONDES Bermuda, April Keflavik, August Sable Island, September observations model

MODEL EVALUATION WITH NARE 1997 AIRCRAFT DATA (NORTHWEST ATLANTIC) Sep.13: clean day Sep.16: U.S. outflow day observationsmodel CO O3O3 NO y NO

MODEL EVALUATION WITH ACSOE 1997 AIRCRAFT DATA (NORTHEAST ATLANTIC) Clean day European outflow day CO O3O3

ORIGIN OF OZONE AT BERMUDA IN SPRING: production over U.S. is dominant source

ENHANCEMENTS OF SURFACE OZONE IN NORTH AMERICA AND EUROPE DUE TO ANTHROPOGENIC EMISSIONS IN THE OTHER CONTINENT N.American influence on Europe European influence on N. America GEOS-CHEM model results, July 1997

FUTURE RESEARCH NEEDS BETTER COUPLING OF 3-D MODELS AND OBSERVATIONS 3-D CHEMICAL TRANSPORT MODELS INTERCONTINENTAL TRANSPORT OF POLLUTION SATELLITE OBSERVATIONS Global and continuous but few species, low resolution AIRCRAFT OBSERVATIONS High resolution, targeted flights provide critical snapshots for model testing SURFACE OBSERVATIONS high resolution but spatially limited Source/sink inventories Assimilated meteorological data Chemical and aerosol processes

TROPOSPHERIC NO 2 FROM GOME (July 1996): mapping of NO x emissions [Martin et al., 2001] Scattering AMF using local shape factors from the GEOS-CHEM model and accounting for local cloud information (fraction, top, optical depth) GEOS-CHEM global 3-D model with GEIA inventory for NOx (scaled to 1996)

FORMALDEHYDE COLUMNS FROM GOME (July 1996): mapping of isoprene emissions [Palmer et al., 2001]

MOPITT validation during TRACE-P: 40N, 132W 0226 at 2005Z; double spiral bracketing in time the MOPITT overpass. Solid stratus deck with tops at 3.5Kft, otherwise clear sky. Layer at 4-7 km is aged Asian pollution. DC-8 CO data (Sachse) MOPITT observations of CO

CONVERGENCE OF SCALES FOR AIR QUALITY AND CLIMATE RESEARCH AIR QUALITY RESEARCH urban regional continental intercontinental global CLIMATE RESEARCH Let’s take advantage of synergistic opportunities!

Quantify the export of radiatively and chemically important trace gases and aerosols from North America Relate these exports to surface sources and sinks and to continental boundary layer chemistry INTERCONTINENTAL TRANSPORT EXPERIMENT – NORTH AMERICA (INTEX-NA) NASA/GTE two-aircraft mission for summer 2004 based in Maine, Wisconsin, California OBJECTIVES: Coordinated with: North American Carbon Cycle (NACC) NOAA New England pollution study European research programs

INTEX MISSION DESIGN P-3 DC-8 Outflow PACIFICATLANTIC NORTH AMERICA Emissions/ Deposition Inflow 3-D chemical models: forecasts/analyses DC-8 Satellite data for gases/aerosols (near real-time) Surface sites