Calibrating the quickSCAT/SeaWinds radar for measuring rainrate over the oceans and improving wind vector estimates

The sensitivity of the SeaWinds scatterometer to rainrates as small as 0.5 mm/hr (for winds less than 6m/s) is a result of backscattering and attenuation by the rain column. This creates both a need to correct the measured radar cross sections, to improve the accuracy of wind vector estimates, and an opportunity to estimate the ocean rain rate to supplement ocean precipitation studies. Both the sea surface and atmospheric rain contribute to the total radar cross section. A comprehensive method is being developed to identify, separate and estimate these two different targets. The goal is to utilize this new method to correct the measured NCRS so that the sea surface reflection can be estimated in a manner that will lead to more accurate wind vector estimates. Also an opportunity exists to estimate the ocean rain rate to supplement ocean precipitation studies.