Shortwave Aerosol Radiative Forcing from MODIS and CERES observations over the oceans

[1] Using spatially and temporally collocated data sets from the Clouds and Earth’s Radiant Energy System (CERES) and Moderate-Resolution Imaging Spectroradiometer (MODIS) instruments on the Terra satellite, a new strategy is presented for studying the Shortwave Aerosol Radiative Forcing (SWARF) over the global oceans. Using collocated data, for September 2000, the global averaged optical thickness (t0.55) for cloud-free CERES pixels is 0.07 with a SWARF of 6 Wm . The t0.55 and SWARF values derived from two independent instruments are in excellent agreement with the following relationship: SWARF = 0.35 105.34t0.55 + 61.47t0.55 2 (0 t0.55 0.7) Wm . The synergistic use of the MODIS and CERES data sets can be used to provide independent estimates of SWARF, and can be used as a validation tool for studies that attempt to model the role of aerosols on climate.