Abstract and keywords
Abstract (English):
The coastal zones of the Laptev and East-Siberian seas are characterized by the highest erosion rates in the Arctic. Thermal abrasion is the leading geomorphological process in the region, with average rates of 1 to 4 m/yr. On the basis of shore segmentation, coastal erosion rates were analysed for each segment of coast. The mean rate of coastal retreat for the Laptev and East-Siberian seas was calculated and estimated to be 0,8 m/yr. In recent decades, the Laptev and East-Siberian sea regions have experienced a warming trend. Under these conditions, erosion rates of ice rich coasts on several key sites have increased 1,5–2 times during the last 10–12 years. Sediment and organic material inputs for the Laptev and East-Siberian seas were estimated and found to be respectively (1,6 and 2,4 103 t/yr for sediment and 62,2 and 90,2 103 t/yr for organic material). The data obtained were compiled into an electronic coastal database for the study region. Using the database, 16 lithologic, morphologic, morphometric and dynamic parameters were determined for each coastal section. The processes of cryogenic morphogenesis form rather specific coastal landscapes within the studied coasts. In studied region the rates of coastal transformation is much faster then in other Arctic areas. This study has shown that 10,7 km2/yr of land is lost annually along the Arctic seas of East Siberia.

Keywords:
The coastal zones
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