Ku- and Ka-Band Ocean Surface Radar Backscatter Model Functions at Low-Incidence Angles Using Full-Swath GPM DPR Data

This paper presents the results of first characterization coincident Ku- and Ka-band ocean surface normalized radar cross section measurements at earth incidence angles 0°–18° using one year wide swath Global Precipitation Measurement (GPM) mission dual frequency precipitation (DPR) data. Empirical geophysical model functions were derived for both bands, isotropic directorial sensitivity assessed, finally, sea temperature (SST) dependence backscatter, investigated. The exhibited higher vector wind a low-to-moderate speeds regime, SST effects also observed to be substantially larger than Ku-band.