Fifty four years of coastal erosion and hydrometeorological parameters in the Varandey region, Barents Sea

摘要

The southeast coastline of the Barents Sea in the area of the Varandey settlement is characterized by warm permafrost. Coastal studies conducted since the early 1980s have shown coastal retreat with average erosion rates of up to 2-5 m/yr from 1969 to 1987 at different locations in the area. The present study summarizes long-term (1951-2013) observations of environmental forcing in the area, and estimations of retreat rates based on recent fieldwork (2011-2013) and remote sensing studies (1961-2012). Such data is of primary importance for any infrastructure developments in the study area. The coastline was divided into three conditional geographical sectors: Pesyakov, Varandey, and Medynskiy. It was found that the average erosion rate in eroding parts of Pesyakov sector was 2 m/yr, in the western part of Varandey sector-1.8 m/yr, and in the entire Medynskiy sector-2.3 m/yr over the last 54 years. Remote sensing observations documented the destruction of numerous buildings in the coastal zone of the Novyy Varandey settlement in 2004-2012. A striking coastal bluff recession of 19.6 m/yr over the 15-km-long coastline in Medynskiy was observed between 2010 and 2011, following a storm surge in the area in the summer of 2010. Fluctuations of environmental forcing (air temperatures, wave energy factor, significant wave height, and sea level) were observed in the Varandey area in 1979-2013. The long-term evolution of environmental forcing exhibits an increasing trend. The increase (0.6-4.8 m/yr) of average long-term erosion rates in the Medynskiy sector from 1961 to 2013 followed the evolution of environmental forcing in 1979-2013. Different coastal erosion responses and processes varying from a stable situation to active erosion due to mechanical wave action, thermal abrasion, thermal denudation, or a combination of these processes were identified in the Varandey area.