ИСТИНА

The arctic coasts, largely composed of permafrost, are dynamically active with a tendency to retreat with a mean rate of about 0.5 m/yr. In the last decades due to global climate changes and construction in the coastal zone, the rates of retreat have increased at many sites so that a large part of accumulative coasts turned to erosional. We studied a 7 km long section of the western coast of the Gydan Peninsula in the area of Salman gas field development. Based on multi-temporal satellite imagery interpretation, field geological and topography surveys, we assessed the dynamics of the coast for the periods before and after the facilities' construction.The coast at the area of study is a low-lying (0.5-2 m high) sandy accumulative marine terrace, and before the start of construction (2012-2014) it showed low dynamics with predominantly accumulative processes: mean rate of coastline progradation was 4.1 m/yr. With the beginning of port construction, the dynamics of the coast have changed: in 2014-2017 ¾ of the coast of the studied area experienced retreat (average retreat rate -5.8 m/yr, up to 28.5 m/yr in close proximity of the constructed facilities). We propose that coastal erosion intensification results from human impacts. After 2017, the rates of coastal destruction decreased, but the trend towards retreat continued.