Passive Remote Sensing Of Oceanic Whitecaps: Updated Geophysical Model Function

Satellite-based estimates of whitecap fraction W provide consistent global, long-term data useful to quantify air-sea processes. Our first algorithm providing satellite-based W data uses passive microwave observations from WindSat at low spatial resolution, early version of the WindSat geophysical model function (GMF) for surface emissivity and the atmosphere, and input variables from various sources. This algorithm has been recently updated with new input data and the latest versions of the WindSat GMF to produce W data at higher spatial resolution. The updated algorithm yields improved W data as they show consistency at different microwave frequencies and expected threshold behavior at all frequencies.