ISSN 2070-7401 (Print), ISSN 2411-0280 (Online)
Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa
CURRENT PROBLEMS IN REMOTE SENSING OF THE EARTH FROM SPACE

  

Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa, 2026, V. 23, No. 1, pp. 231-244

Development of a geophysical model function for surface wind speed retrieval in conditions of Gorky Reservoir

O.S. Ermakova 1 , N.S. Rusakov 1 , E.I. Poplavsky 1 , O.A. Danilicheva 1 , G.A. Baidakov 1 , D.A. Sergeev 1 
1 Institute of Applied Physics RAS, Nizhny Novgorod, Russia
Accepted: 13.10.2025
DOI: 10.21046/2070-7401-2026-23-1-231-244
The paper is devoted to the development of a method for the retrieval of wind speed at a standard meteorological height based on electromagnetic scattering calculated within a two-scale model and verified using data from the Sentinel-1 C-band synthetic aperture radar (SAR) for direct VV polarization and collocated meteorological station measurements. The method is based on a new geophysical model function (GMF) representing the relationship between specific effective scattering cross-section and surface wind speed, incidence angle of microwave signal, wind direction, and wave fetch. When developing the new GMF, a spectrum specific to inland waters was used, taking into account the range of dimensionless fetches from 2000 to 20 000. The GMF proposed in this work was verified based on in situ wind speed measurements conducted in the southern part of Gorky Reservoir between 2017 and 2019 along with collocated images from Sentinel-1A, -1B SARs. It was shown that the accuracy of wind speed reconstruction based on the proposed GMF is higher than that obtained using the CMOD7 models and models developed for the Caspian Sea.
Keywords: SAR image, C-band, Sentinel-1, co-polarization, inland water body, geophysical model function, fetch, two-scale model
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