Validation of QuikScat Tropical Cyclone Winds

Better tropical cyclone intensity predictions require accurate measurement of storm wind speeds. Buoys, aircraft, and various visual and enhanced IR imagery techniques are used to determine the winds in tropical cylcones. In contrast to sparse observations or to the limitations of visible and IR imagery, microwave scatterometers can see through clouds to measure winds at the ocean surface. Significantly more observations are available from scatterometers even though rain scattering and rain induced sea-surface roughening may affect wind retrievals. QuikScat, a conical scanning radar scatterometer, was launched summer 1999 in time for the tropical storm season. We demonstrate that QuikScat wind vector measurements from outside the rain band regions can be used to estimate the sustained wind speed and therefore the intensity of a tropical storm. Prior to using QuikScat winds, the data require validation by comparison with other available wind measurements. In this talk, we present our comparison results and estimate the quality of QuikScat winds within selected Atlantic and Pacific tropical cyclones.