Land Contamination Correction for Passive Microwave Radiometer Data: Demonstration of Wind Retrieval in the Great Lakes Using SSM/I

Passivemicrowave radiometer data over the ocean have beenwidely used, but data near coastlines or over lakes often cannot be used because of the large footprint with mixed signals from both land and water. For example, current standard Special Sensor Microwave Imager (SSM/I) products, including wind, water vapor, and precipitation, are typically unavailable within about 100km of any coastline. This paper presents methods of correcting land-contaminated radiometer data in order to extract the coastal information. The land contamination signals are estimated, and then removed, using a representative antenna pattern convolved with a high-resolution land–water mask. This method is demonstrated using SSM/I data over the Great Lakes and validated with simulated data and buoymeasurements. The land contamination is significantly reduced, and thewind speed retrieval is improved. This method is not restricted to SSM/I and wind retrievals alone; it can be applied more generally to microwave radiometer measurements in coastal regions for other retrieval purposes.