Retrieval of Surface Wind Speed and Aerosol Optical Depth over the Oceans from AVHRR Images of Sun Glint

Abstract

Abstract This paper investigates the feasibility of recovering both the tropospheric aerosol loading and the surface wind speed from satellite measurements of the radiance within cloud free regions of sun glint over the ocean surface. The method relies on the marked distinction between the spatial variation of the surface reflected radiance and the atmospheric radiance. Analysis of AVHRR channel 2 (720–980 nm) data from a 128 km × 8 km test site at 17°S and 162°E indicates that the retrieval of aerosol loading and wind speed is insensitive to the size of the dataset, once a certain minimum size has been reached. Extensive numerical simulations reveal zones over the oceans where it is possible to retrieve the aerosol loading and surface wind speed with accuracy better than 10%. The recovery of wind speed to this accuracy is feasible over a somewhat larger area than for the aerosol loading.