Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa, 2023, Vol. 20, No. 6, pp. 234-246
Experimental studies of rough sea surface effective emissivity
I.N. Sadovsky
1, 2 , D.S. Sazonov
1 1 Space Research Institute RAS, Moscow, Russia
2 MIREA — Russian Technological University, Moscow, Russia
Accepted: 08.11.2023
DOI: 10.21046/2070-7401-2023-20-6-234-246
This paper presents the results of experimental work aimed at studying the behavior of effective emissivity of sea surface for various wave conditions and states of the surface layer of the atmosphere. The experiment was carried out at the Katsiveli oceanographic platform of the Black Sea hydrophysical test site of the Russian Academy of Sciences (BGP RAS) located at the southern tip of the Crimean Peninsula. Changes in the radiation intensity of the ocean-atmosphere system were recorded by two identical radiometer-polarimeters with an operating wavelength of 8 mm. The resulting brightness temperatures at vertical and horizontal polarizations were recalculated into the corresponding values of effective emissivity of the disturbed water surface. From analysis of the vertical viewing angle dependence of this parameter, its sensitivity to the state of the near-water layer of the atmosphere determined by the value of the integral absorption at a frequency of 36.0 GHz is shown. Using the example of azimuthal dependences, the effect of azimuthal anisotropy of effective emissivity is shown and the results of approximating this effect with a biharmonic function are presented. The work is preliminary in nature and qualitatively demonstrates these effects.
Keywords: effective emissivity, rough water surface, microwave radiation of the ocean-atmosphere system, radiometer-polarimeter
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