A technique for deducing wind direction from satellite microwave measurements of wind speed

A technique is presented to deduce wind direction from satellite microwave measurements of wind speed information. The technique, based on simple Ekman boundary layer dynamics, makes use of surface pressure fields routinely analyzed at the National Meteorological Center. To demonstrate its application, a three-day sample of altimeter and scatterometer wind speed data, taken from the Seasat satellite, was used to deduce wind directions. The deduced wind vectors are presented and compared with NMC 1000 mb wind analyses, and with the subjectively edited vector winds. It is suggested that the technique proposed in this study could be applied to the ocean surface wind speed measurements derived from a satellite altimetric mission to produce more useful parameter, namely, the ocean surface wind vector. This technique can also be used to objectively resolve potential ambiguities in scatterometer wind directions.