Revealing and mapping the southern part of the Kunashir island coastline changes using space images of very high spatial resolution

Abstract

In the paper the authors carry out the changes of the coastline position by interpretation of the multi-temporal images taking into account the influence of tidal fluctuations. Images from satellites KeyHole and satellite WorldView-2 were used. Keyhole images were acquired from 1964 to 1975; WorldView-2 image was acquired in 2013. Thus, the study period was 48 years. Georeferencing for KeyHole images was made using WorldView-2 image. The impact of tides on the displaying position of the coastline on the satellite images was eliminated by the introduction of a correction for the deviation of the water level from the long-term average one. The result is a map that represents the areas of the coast that are actively changing. Veslovsky peninsula changes are stable, a constant coast increase in its southern part can clearly be seen. Increases for the year can vary in different parts of the coast, gain values are from 3 to 8 m. Cape Paltusov has a complex shape, it represents three alternating sand bars that have a common base and southwest-northeast direction. Increase of the youngest bar began in between 1968 and 1975. During the period from 1960 to 2013, the increase of the shoreline of the study area was about 350 m. It has been revealed that the study area is increasing for about 5 meters per year.