北极海岸正逐渐被侵蚀
Bremerhaven/Geesthacht/Potsdam, 14 April 2011. The coastline in Arctic regions reacts to climate change with increased erosion and retreats by half a metre per year on average. This means substantial changes for Arctic ecosystems near the coast and the population living there. A consortium(财团,联合) of more than thirty scientists from ten countries, including researchers from the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association and from the Helmholtz Centre in Geesthacht, comes to this conclusion in two studies published in Estuaries and Coasts and online on www.arcticcoasts.org. They jointly investigated over 100,000 kilometres and thus a fourth of all Arctic coasts and their results have now been published for the first time. The changes are particularly dramatic in the Laptev, East Siberian and Beaufort Seas, where coastal erosion rates reach more than 8 metres a year in some cases. Since around a third of the world's coasts are located in the Arctic permafrost(永久冻土) , coastal erosion may affect enormous areas in future. In general Arctic coasts react more sensitively to global warming than coasts in the mid-latitudes. Up to now they have been protected against the eroding force of the waves by large sea ice areas. Due to the continuous decline in sea ice, this protection is jeopardised and we have to reckon with rapid changes in a situation that has remained stable for millennia.
Two thirds of the Arctic coasts do not consist of rock, but of frozen soft substrate (permafrost). And precisely these coasts are extremely hard hit by erosion. As a rule, Arctic regions are quite thinly populated. However, as nearly everywhere in the world, the coasts in the far north are important axes for economic and social life. The growing need for global energy resources as well as increasing tourism and freight(货运,运费) transport additionally intensify anthropogenic(人为的) influence on the coastal regions of the Arctic. For wild animal stocks, like the great caribou(北美驯鹿) herds of the north, and the widespread freshwater lakes near the coast progressive erosion brings about significant changes in ecological conditions.