The Azimuthal Dependence of the Microwave Emissions of a Water Surface Based on Remote Measurements at the Black Sea
This paper presents an analysis of the experimental measurements of the azimuthal anisotropy of the microwave emissions of a rough water surface. The experimental data were obtained using microwave radiometers with operating frequencies of ~37 GHz (a wavelength of ~8 mm) on the oceanographic platform of the Black Sea Hydrophysical Experimental Facility of the Russian Academy of Sciences in the period from 2005 to 2016. This paper describes the azimuthal anisotropy effect, experimental studies, measurement methods, and data processing. A qualitative comparison of the measurement results with the model calculations and other experimental studies of anisotropy was performed. It was shown that there is a strong sensitivity of the variation in the radio emissions of a rough water surface, both to the wind speed and to its direction at different incidence observation angles.
Keywords:remote sensing azimuthal anisotropy brightness temperature modeling radiometer microwave emission wind speed and direction
The authors are grateful to the staff of the Earth Studies from Space Department of the SRI RAS who participated in these studies in different years. We would especially like to mention M.N. Pospelov.
This work was supported by the Russian Foundation for Basic Research, grant no. 15-05-08401_a.
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