NEW RESEARCH: GREENLAND’S GLACIERS HAVE BEEN RECEDING FOR 100 YEARS
Press release issued on 21 August 2006
Researchers from the University of Aarhus can now present the results of the most extensive study of Greenland’s glaciers ever carried out. The study shows that the recession of Greenland’s glaciers due to melting is not a recent phenomenon: the glaciers have been receding for more than 100 years. The results are being presented by the glaciologists Jacob Clement Yde and Niels Tvis Knudsen at an international conference on the effects of climate change on the world’s glaciers starting today in Cambridge, UK.
The two researchers have studied the way in which the glaciers on Disko Island in West Greenland have moved between the end of the 19th century and today. Their studies show that the glaciers receded constantly between the end of the 19th century and 1953. The recession between 1920 and 1953 was not influenced by a significant 3-4oC temperature increase in Greenland during this period, and the recession has continued since 1953 at a speed of 8 metres a year. During this period none of the glaciers has grown in length: 69 per cent have receded, and 31 per cent are unchanged. The recession was greatest between 1964 and 1985. The current increase in temperature in Greenland, which started in the mid-1990s, cannot be registered in the movements of the glaciers yet.
“The study published today covers 247 glaciers, making it the most extensive study of glacial movement in Greenland ever undertaken. We have studied 95 per cent of the area covered by glaciers on Disko. Everything points to the fact that our results also apply to other similar coastal glaciers elsewhere in Greenland – they too will have receded or even disappeared completely during the past 100 years”, reports glaciologist Jacob Clement Yde.
Galloping glaciers – living a life of their own
The studies have also provided the researchers with new research results regarding what are known as “galloping glaciers” on Disko Island. Galloping glaciers are glaciers that progress quickly over the space of a few years – by up to 50 metres a day – after which they slowly recede by 20 metres a year and then suddenly start progressing again hundreds of years later. Galloping glaciers are not relevant to the discussion regarding the effects of climate change on glaciers, because they function independently of the climate. The researchers can now show that there are far more galloping glaciers than was previously believed. New analysis of aerial photographs and satellite photos has identified 75 galloping glaciers instead of only 20.
发表于 2006-8-28 20:38:56
