| Summary: | Abstract: The Arctic ice sheet has been declining since the end of the 19.th century both with consideration to its Area and to its thickness. Since the 1960.s this development has been accelerating and as recently as 2007 the ex-tent of the ice was smaller than at any time since observations began. Since then the ice has however recovered slightly and is now close to the negative trend line. Since the temperature increases in the arctic are between two and three times the magnitude of the increases in the global mean temperature it is possible to at an early date see the effects of global warming, this further increases the interest in the ice sheet´s development. The purpose of this paper has been to examine the processes that impact the ice and to examine why the ice sheet is decreasing. The paper is a literature review and the source material has primarily consisted of scientific papers. The papers used have been using several different methods to gather information about the ice, primarily modeling, satellite and submarine data has been used. However some articles have also been used different methods such as gathering and analyzing drift wood, observing beach ridges and measuring the surface temperature around the Arctic. The picture that emerges from these papers is that in the short term the ice is mainly impacted by temporary weather patterns, however in the longer term rising temperatures are driving the changes since the temperature is following a very clear trend. While the extent of the ice sheet is gradually declining and it´s thickness is gradually decreasing it is also growing more unstable, this is because thick ice has a stabilizing effect on the ice sheets extent. Models of the ice sheets future points to an ice free arctic ocean in September at some point after 2040. In a historical perspective this won´t be unique however. During the last 10,000 years the ice sheets extent has been both far larger and far smaller than it is today Sammanfattning: Det Arktiska istäcket har sedan slutet av ...
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