L-band doppler radar echoes of the sea surface in coastal zone

A remote sensing experiment using an L-Band radar was conducted in a nearshore environment. The results obtained contribute to identify some aspects of the coherent Lband response of the sea, specified by the Doppler spectrum, in neargrazing conditions. At low winds the radar response is of Bragg type. The asymmetry of Doppler spectra varies with wind direction. Surface current measurements were performed from Doppler spectra and assessed by in situ measurements. At high winds the radar response is of Bragg type for VV polarization but not for HH. We show that fast scatterers detected in HH are linked to the dominant waves, which do not propagate in direction of the wind in the complex coastal area considered. Measurements of attenuation with distance of radar signals are also presented.