Areas of Heavy Permanent Oil Pollution of the Caspian Sea Surface Identified by Use of Satellite Remote Sensing

Abstract

The paper provides an outlook of regions with the heaviest Caspian Sea surface pollution. The research is directly aimed at solving environmental protection problems. The results are based on the analysis of long-term data series from satellite Synthetic Aperture Radars (SAR) and satellite multispectral optical sensors obtained over a five-year observation period from 2017 to 2021. Quantitative estimates of interannual, seasonal and spatial variability of oil pollution on the surface of the Caspian Sea were obtained. The relative input of pollution caused by different sources to total oil pollution of the Caspian Sea surface is assessed based on satellite data. Maps of oil pollution have been constructed to evaluate the likelihood of pollution of various sea surface areas. Results include the discovery of significant seasonal variability in the distribution of natural oil films in regions of oil seeps from the seabed. The influence of eddy dynamics on the spread of oil films and its contribution to the cross-shelf transport of oil pollution is noted. The presented results further evidence the need for continuous satellite monitoring of areas with heavy oil pollution outlined in the paper.