Monitoring the dynamics of the Caspian Sea coastline using high-resolution satellite data
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https://doi.org/10.32523/3107-278X-2026-155-2-105-121Keywords:
Caspian Sea, coastline, high-resolution PlanetScope imagery, satellite altimetry, sea level changeAbstract
This article presents the results of comprehensive monitoring of coastline dynamics in the northeastern Caspian Sea from 2017 to 2024. The study is based on the analysis of high-resolution satellite imagery (PlanetScope) and multimission altimetry data (DAHITI). The use of an automated satellite imagery processing algorithm, including the calculation of NDVI and NDWI spectral indices to identify the land-water boundary and coastline vectorization, made it possible to accurately record a large-scale sea regression, expressed as a reduction in the water surface area of the study area by 5 416 km² and a drop in its level by 1,19 m. Particular attention is paid to the identified correlation between hydrological indicators and morphometric changes in the coast. The average area sensitivity coefficient to level changes was found to be 45,5 km²/cm, with an acceleration in the rate of drying of shallow areas recorded in 2024. The results of this study confirm the high efficiency of combining satellite altimetry and high-resolution remote sensing data to obtain reliable quantitative characteristics of water conditions under conditions of intense climate change. The resulting quantitative characteristics can be used in planning economic activities and developing measures to adapt coastal regions to the ongoing sea level decline.
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Copyright (c) 2026 Т. Дедова, Л. Балакай, Н. Баширова, Б. Искаков, А. Мерекеев, Г. Кайранбаева (Автор)
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