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Global Retrieval of Aerosol Single Scattering Albedo from Satellite Observations. Rong-Ming Hu and Randall Martin. Inspiring Minds. Retrieval of Aerosol Single Scattering Albedo (SSA).
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Global Retrieval of Aerosol Single Scattering Albedo from Satellite Observations Rong-Ming Hu and Randall Martin Inspiring Minds
Retrieval of Aerosol Single Scattering Albedo (SSA) • Determined with radiative transfer calculation as SSA that reproduces TOMS Aerosol Index when constrained by MODIS aerosol optical depth and GEOS-CHEM aerosol vertical profile. MODIS AOD TOMS AI LIDORT SSA Calculated Observed (TOMS) AI GEOS–CHEM Aerosol Profile
TOMS Aerosol Index 331 nm and 360 nm
Optical depth at 360nm 1.50 1.00 11. 0.05 0.01
Aerosol profile from GEOS-CHEM and validation with ARM data Southern Great Plains, Lamont, Oklahoma (DOE/ARM site). Results are for 324 profiles from March, 2000 to March, 2003. Solid: GEOS-CHEM simulations. Asterisk, plus, diamond, triangle and square: NOAA/CMDL measurements.
Validation with in situ lidar data(April, 2001) Solid: GEOS-CHEM simulations. Asterisk: lidar measurements in Cheju island (SNU, South Korea) Gobi Desert Dust Storm (MODIS). Cheju
Intercomparison with AERONET square: MAM, asterisk: JJA, triangle: SON, plus sign: DJF.
Sensitivity to Aerosol Optical depth and surface reflectivity Solid: surface reflectivity=0.05. Dashed: surface reflectivity=0.08. Dotted: surface reflectivity=0.15.
Conclusion • Low values of aerosol single scattering albedo near 0.8 occur in biomass burning and mineral dust regions. • Seasonal variation of single scattering albedo is associated with both mineral dust and biomass burning. • Retrieval results present a high degree of consistency with AERONET measurements; the correlation coeffcient, slope and intercept are 0.75, 0.93 and 0.078 respectively. • The dominant terms of retrieval uncertainty are the Ångström exponent, the aerosol optical depth and aerosol profiles contributing to a total uncertainty of 15 percent.