1. Satellite Observations of Tropospheric Gases and Aerosols Randall Martin With contributions from: Rongming Hu (Dalhousie University) Chris Sioris, Xiong Liu, Kelly Chance (Smithsonian Astrophysical Observatory) Tom Ryerson, Andy Neuman (NOAA/CIRES) Ron Cohen (Berkeley) Aaron Swanson, Frank Flocke (NCAR)

2. Space-based Measurements of Tropospheric Composition Related to Both Air Quality and Climate SensorTOMSGOMEMOPITTMISRMODISAIRSSCIA- MACHY TESOMICALIOP Platform (launch) multi (1979-) ERS-2 (1995) Terra Aqua (1999) ( 2002) Envisat (2002) Aura (2004) Calipso 2005 ozoneX (low lat) XXX COXXX NO 2 XXX HCHOXX aerosolXXXXXX

3. Retrieval of Tropospheric NO 2 from SCIAMACHY Spectral Fit Remove Stratosphere Total NO 2 Slant Column Tropospheric NO 2 Slant Column Calculate AMF Tropospheric NO 2 Column Martin et al., 2002, 2005 Martin et al., 2002 Palmer et al. 2001 Martin et al., 2002, 2003, 2005 Mean Total Uncertainty ±(5x10 14 molec cm -2 + 30%) Scattering by Earth surface and by atmosphere

4. Significant Agreement Between Coincident Cloud-Filtered SCIAMACHY and ICARTT In-Situ Measurements In Summer 2004 r = 0.78 slope = 0.82 1:1 line Ryerson (WP-3D) Cohen (DC-8) Chris Sioris Cloud-radiance fraction < 0.5 In-situ measurements below 1 km & above 3 km Assume constant mixing ratio below lowest measurement Add upper tropospheric profile from mean obs In Situ NO 2 Columns NASA DC-8NOAA WP-3D SCIAMACHY NO 2

5. Cloud-filtered Tropospheric NO 2 Columns Retrieved from SCIAMACHY May-Oct 2004 detection limit

6. Error weighting Conduct a Chemical Inversion & Combine Top-Down and Bottom-up Inventories with Error Weighting A posteriori emissions Top-Down Emissions 10 15 molec N cm -2 A Priori NOx Emissions SCIAMACHY NO 2 Columns 10 11 molec N cm -2 s -1 GEOS-CHEM model GEIA

7. May-Oct 2004 Global Optimal Emission Inventory Reveals Major Discrepancy in NOx Emissions from Megacities r 2 =0.82 vs a priori

8. In Situ Airborne Measurements Over and Downwind of New York City Support A Posteriori Inventory In Situ GEOS-CHEM (A priori) GEOS-CHEM (A posteriori) P-3 Measurements Tom Ryerson (NOAA) Aaron Swanson Andy Neuman Frank Flocke (NCAR) (CIRES/NOAA) Large Change in NOx Emissions Near New York City 10 11 atoms N cm -2 s -1  10 11 atoms N cm -2 s -1 A posteriori A posteriori – A priori 7.8 Tg N 0.6 Tg N r 2 = 0.92 7.2 Tg N A priori

9. Liu et al., submitted Direct Retrieval of Tropospheric Ozone from GOME Using Optimal Estimation in Ultraviolet with TOMS V8 a priori GOMEGEOS-CHEM Tropospheric Ozone Column (Dobson Units)

10. Aerosol Absorption Contributes to Differences Between Aerosol Optical Depth and the Absorbing Aerosol Index July 2000 1.5 1.1 0.8 0.4 0 3.0 2.2 1.6 0.8 0 July 2000 MODIS TOMS

11. Retrieval of Aerosol Single Scattering Albedo Determined with radiative transfer calculation as Retrieval of Aerosol Single Scattering Albedo Determined with radiative transfer calculation as SSA that reproduces TOMS Aerosol Index when constrained by MODIS aerosol optical depth Rongming Hu July 2000 r = 0.8 Slope = 1.01 Intercept = -0.02

12. Acknowledgements Rongming Hu (Dalhousie University) Chris Sioris, Xiong Liu, Kelly Chance (Smithsonian Astrophysical Observatory) Tom Ryerson, Andy Neuman (NOAA/CIRES) Ron Cohen (Berkeley) Aaron Swanson, Frank Flocke (NCAR) Funding: National Aeronautics and Space Administration (NASA) Canadian Foundation for Climate and Atmospheric Sciences (CFCAS) Canadian Foundation for Innovation (CFI) Nova Scotia Research and Innovation Trust (NSRIT)