The emissivity of foam-covered water surface at L-band: theoretical modeling and experimental results from the FROG 2003 field experiment
PublisherIEEE Press. Institute of Electrical and Electronics Engineers
Rights accessOpen Access
Sea surface salinity can be measured by microwave radiometry at L-band (1400–1427 MHz). This frequency is a compromise between sensitivity to the salinity, small atmospheric perturbation, and reasonable pixel resolution. The description of the ocean emission depends on two main factors: 1) the sea water permittivity, which is a function of salinity, temperature, and frequency, and 2) the sea surface state, which depends on the wind-induced wave spectrum, swell, and rain-induced roughness spectrum, and by the foam coverage and its emissivity. This study presents a simplified two-layer emission model for foam-covered water and the results of a controlled experiment to measure the foam emissivity as a function of salinity, foam thickness, incidence angle, and polarization. Experimental results are presented, and then compared to the two-layer foam emission model with the measured foam parameters used as input model parameters. At 37 psu salt water the foam-induced emissivity increase is 0.007 per millimeter of foam thickness (extrapolated to nadir), increasing with increasing incidence angles at vertical polarization, and decreasing with
CitationCamps, A. [et al.]. The emissivity of foam-covered water surface at L-band: theoretical modeling and experimental results from the FROG 2003 field experiment. "IEEE transactions on geoscience and remote sensing", Maig 2005, vol. 43, núm. 5, p. 925-937.