Microwave wind direction retrieval over Antarctica

Over large regions of Antarctica, ice sheet and bedrock topography and the snow deposition, drift, and erosional environment combine to produce roughness on various scales. The roughness influences the microwave backscattering and emission properties of the surface, introducing azimuth-angle dependencies in the satellite observation data. The authors explore the use of data from SeaWinds on Quikscat, NSCAT, ERS AMI scatterometer mode, and SSM/I to study surface roughness effects in Antarctica. A simple empirical model for the azimuth variation in the radar backscatter is developed. Azimuthal variations in the data are highly correlated with the direction of the katabatic wind flow.