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The glaciers in southeast Greenland are retreating rapidly with theongoing global climate change. But now research from the Universityof Copenhagen shows that the glaciers can recuperate within a shorttimeframe if temperatures are to drop. The results are based on a collection of Danish aerial photoscombined with both old and modern satellite imagery as well asfield work. The scientific results have created internationalattention and have been published as a cover story in the highlyesteemed journal Nature Geoscience. "We have managed to get an overview of the glacial evolution over aperiod of 80 years. This is the first time ever this has been donein a study of glaciers in Greenland. Results show that glaciers canrecuperate within a short time frame if climate changes andtemperatures drop, as it has in a period after the 1940s," says PhDstudent and lead-author on the project Anders Bjork, from ProfessorEske Willerslev's Centre for GeoGenetics from University ofCopenhagen Anders Bjork adds: "Most of the scientific foundation, models, andtheories on glaciers in Greenland and how global warming affectsthem are based on observations from satellites over the last tenyears. Otherwise scientists have had to use previous warming eventsway into the past when wanting to compare today's massive retreat." A fight for land between Denmark and Norway The Danish explorer Knud Rasmussen and his seventhThule-expedition in 1932-33 is a significant cause for the recentpublication from Anders Bjork and Dr. Kurt H. Kjaer from theNatural History Museum of Denmark, University of Copenhagen. Results have created international attention as Greenland stands asan important region for northern latitudes are affecting the restof the earth's climate - including changes in glacial conditionsand related sea-level rise. Originally the many aerial photos, which have been achieved DanishNational Survey and Cadastre, were used for producing new maps ofthe region in the early 1930s, as Denmark and Norway were fightingover the right of disposal of East Greenland, a fight withoutcasualties which Denmark won at the International Court in Haag inthe Netherlands in 1933. Photos get a renaissanse With help from the scientists and the Danish National Survey andCadastre, the unique aerial photos have now gained a renaissance ina different setting where climate change and theories as "TheTipping Point" - where nature reaches a point where changes cannotbe reversed are discussed. "We have investigated no less than 132 glaciers on a 600 km coastalstretch in Southeast Greenland, both those who terminate on landand those who calve in the ocean. The historical photos have proven to be extremely valuable, andwith these photos and other aerial photos recorded later duringWWII and satellite imagery we are able to observe glacier change invery long historical context. In the early 1920s and 1930s, temperatures were high, similar tothat of the present, and this affected the glacial melt. At thetime many glaciers underwent a melt similar or even higher thanwhat we have seen in the last ten years. When it became colderagain in the 1950s and 1960s, glaciers actually started growing,"says Dr. Kurt H. Kjaer and underlines: "There should be no doubt that if the current temperature rise inGreenland continues then we will have problems with the melting ofthe glaciers. We are already seeing it now on the marineterminating glaciers where changes in temperature and oceancurrents are influencing their stability. Another remarkablediscovery we did was that the observed changes are not just local,it is happening in the entire region," says Dr. Kjaer. Kurt H. Kjaer has previously worked with his colleague Svend Funderfrom Center for GeoGenetics on investigating sea ice extent in theArctic Ocean. Results showed that the sea ice extent has been farfrom stable throughout the last 10,000 years. Read the scientists' newly published paper in Nature GeoScience. We are high quality suppliers, our products such as Ibm Security Chip Manufacturer , Oki Toner Reset Chip for oversee buyer. To know more, please visits Samsung Toner Chips.
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