On the estimation of wind vectors over the sea surface from near-nadir radar observations

The remote sensing of wind vectors over the sea surface using microwave scatterometry has a long history. Traditional scatterometer systems operate at moderate incidence angles in order to emphasize the Bragg scatter component of the sea surface normalized radar cross section (NRCS), and typically require multiple azimuth “looks” in order to reduce ambiguities in the determination of wind direction. In contrast, radar systems designed for atmospheric sensing from aircraft frequently operate in a near-nadir configuration, with cross-track scanning utilized in some cases. This study explores the potential use of such atmospheric radar measurements for wind vector retrieval through a Monte Carlo simulation method. A maximum likelihood estimation of wind vectors is utilized for simulated measurements corrupted by speckle and thermal noise.