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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, 2025, V. 22, No. 3, pp. 235-243

Comparative analysis of Black Sea surface salinity, according to SMAP remote sensing observations and in situ oceanographic data

D.M. Shukalo 1 , T.Ya. Shulga 1, 2 
1 Marine Hydrophysical Institute RAS, Sevastopol, Russia
2 N. N. Zubov’s State Oceanographic Institute, Moscow, Russia
Accepted: 23.04.2025
DOI: 10.21046/2070-7401-2025-22-3-235-243
The purpose of this work is to evaluate remote sensing observations of sea surface salinity (SSS) in the Black Sea. To solve the problem, a comparative analysis of salinity in the Black Sea for 2015–2021 based on the Soil Moisture Active Passive (SMAP) data and in situ oceanographic measurements was performed. It was found that SMAP products underestimate average annual SSS values by 0.25–0.30 psu compared to in situ observations. However, remote sensing data preserve interannual trends in the Black Sea salinity demonstrated by in situ measurements and can replace them with due consideration of the obtained deviations. At the same time, average annual SMAP SSS data show greater tendencies towards salinization with a lower estimate of the averages compared to in situ observations. It is shown that the best agreement between the SMAP mean SSS values and ship observations is provided by the smoothed product with a resolution of 70 km. The results of the surface salinity analysis indicate trends towards stable salinization over the observation period from 2015 to 2021 at a rate of ~0.09 psu/year according to SMAP data and ~0.06 psu/year according to in situ data.
Keywords: Black Sea, surface salinity, remote sensing data, salinization, desalination, SMAP, Bland–Altman plot
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