Correction of Sun glint Contamination on the SeaWiFS Ocean and Atmosphere Products

For remote sensing of the ocean and atmosphere optical properties, the measurement of radiances affected by sun glint has to be avoided and/or masked out. There are usually no meaningful retrievals in regions significantly contaminated by sun glint. The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) is capable of operationally tilting the sensor 20 degrees away from nadir to minimize sun glint contamination. The sun glint mask is computed from the Cox and Munk model [J. Opt. Soc. Am. 44, 838-850 (1954)] and applied to the SeaWiFS data. However, sun glint is still a factor near the subsolar point. We present results that demonstrate the effect of sun glint contamination on retrievals of ocean bio-optical and atmospheric products. We show that, although sun glint contamination has a minor effect on retrieved ocean color products, the effect on retrieved atmospheric products, e.g., aerosol optical thickness, is significant. We describe a sun glint correction scheme implemented in the SeaWiFS data-processing system and compare the results with and without sun glint correction. With sun glint correction the derived ocean and atmospheric products are improved. Also, the sun glint masked area can be reduced and therefore can increase significantly the coverage area near the subsolar point.