Identification and possible correction of rain contamination in QuikScat/SeaWinds wind retrievals

The excellent coverage and wind vector retrieval performance of the SeaWinds scatterometer on QuikSCAT promises to of great value to the operational marine forecasting community. However, recent validation efforts have revealed that rain can have a significant impact on the wind vector retrieval quality. Therefore, several rain flagging methods have been developed by the QuikSCAT calibration/validation team. and are being included in the initial release of QuikSCAT wind data to the scientific community. These rain flags will permit the user to at least identify the retrievals of questionable quality. An evaluation of these rain flags is carried out with the goal of improving our understanding and quantifying the physical mechanisms responsible for wind retrieval performance degradation, and refinements to the rain flags algorithms will be made as necessary. Precipitation products derived from the brightness temperature measurements of SSM/I and TMI are colocated with QuikSCAT retrievals to help quantify the propagation path losses and scattering effects on the QuikSCAT/SeaWinds measurements. An attempt is made to quantify the contributions of rain in the QuikSCAT/SeaWinds measurements, and thus, provide the basis for a possible correction scheme for the rain effects from the QuikSCAT/SeaWinds measurements.