Long-Term Phase Changes In The South Aral Sea Region Lakes

Relevance. A detailed study of the hydrological regime of lakes is an urgent task, however, it should be noted that this issue is complicated by the lack of systematic observations on lakes. In such cases, satellite images can be used to obtain information about water bodies in hard-to-reach areas. The study carried out mapping of six lakes located in the Southern Aral Sea region. The mapping was carried out for different dates and different phases of the hydrological regime of the lakes in the presence of water in them. Methods.For the study area, satellite images from the United States Geological Survey (USGS) research center and the European Commission database for the period 1984-2021 were selected. At the next stage, calculations were carried out using ArcGIS software. To this end, this article examined several methods for decoding satellite images to determine the water surface area of a lake. In the research used hydrological calculations, methods of remote sensing of the Earth (RSE), and “water index” methods for decoding satellite images. In particular, decoding methods of NDWI and MNDWI space images were analyzed to determine the surface area of the lake. Results. As a result of the calculation, the reduction in the area of lakes amounted to 28.92-93.3%. As a result of the research, it was found that all the studied lakes became seasonal. As a result of the research, it was established that lakes Muynak, Saribas, Mezhdurechye and Dautkul have turned into seasonal lakes, while lakes Sudochye and Jyltyrbas still remain permanent.