Ku-band ocean backscatter functions for surface wind retrieval

The accuracy of wind measurements with scatterometer techniques depends on the particular geophysical model function used in the retrieval algorithm. Discrepancies among existing model functions, developed based on a mixture of aircraft and satellite backscatter data acquired previously, will result in differences in retrieved wind fields. The Jet Propulsion Laboratory airborne K_u-band NUSCAT scatterometer was used to obtain an extensive data set over a wide range of wind conditions to provide a more accurate study of ocean radar backscatter signatures. Backscatter was measured during the Surface Wave Dynamics Experiment in an oceanic area off the US east coast. Backscatter data were obtained for both horizontal and vertical polarizations, incidence angles from 100 to 600, and wind speeds up to 15 m s^-1. The measured results are compared with calculated values to assess the existing geophysical model functions for applications to ocean surface wind retrieval