Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa, 2026, V. 23, No. 4, pp. 63-69
Modified method for optimal interpolation of sea level anomalies in the Sea of Okhotsk based on satellite altimetry data
A.A. Romanov 1 , A.A. Romanov 2 1 Moscow State University of Geodesy and Cartography, Moscow, Russia
2 AO Central Research Institute for Machine Building, Korolev, Moscow Region, Russia
Accepted: 21.05.2026
DOI: 10.21046/2070-7401-2026-23-4-63-69
The study aims to modify the method for reconstructing the spatial distribution of sea level anomalies in the Sea of Okhotsk using optimal interpolation. Based on the correlation function parameters of the analyzed variable, it is proposed to introduce an additional spatial filtering procedure into the baseline method. This procedure limits the source data used for reconstructing values at regular grid nodes to a zone with a 300-km radius. Since the area around a node is smaller than the entire Sea of Okhotsk, a procedure to account for long-wave error with a normalized variance of 0.25 must also be introduced when setting up the interpolation problem. The distribution of sea level anomalies from cycle 1070 of the Jason-3 satellite serves as an implementation example for the modified method. The modified method produces spatial distributions similar to the baseline approach but reveals a different upward trend in values relative to the mean sea level of the Sea of Okhotsk. Furthermore, the resulting distribution features less smoothing, ensuring that the dynamic range of the reconstructed altimetry data is consistent with the source data. Concurrently, the mean optimal interpolation error is reduced by up to 2.5 times.
Keywords: satellite altimetry, Sea of Okhotsk, spatial distribution reconstruction technique, optimal interpolation
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