1. Calculating AODs from MODIS radiances Easan Drury G4 - w/ Jacob group @ Harvard July 22, 2004 July 3, 2004

2. Inferring AODs from MODIS radiances ( and using MODIS radiances as the observational variable for constraining modeled aerosols ) α MOLECULAR α AEROSOL α SURFACE Molecular scattering & absorbing Aerosol scattering & absorbing Surface reflectance 2nd assumption1st assumptionWhat we want! α MOLECULAR α SURFACE α AEROSOL

3. Inferring Surface Albedo Visible to IR reflectances: Top of the atmosphere reflectance for the 1x1.25 degree bin. Regress the bottom quartile of visible to IR reflectance. Reflectance ratios during July-August, 2004:

4. GEOS-Chem optical properties

9. MODIS & AERONET AODsAERONET - MODIS AODs Fraction of Pixels used Difference in 10x10km 2 MODIS and AERONET AODs