Antarctic warmth kills ice shelves.Ice shelves along the coast of Antarctica may play the role of the canary in a coal mine when it comes to global warming global warming, the gradual increase of the temperature of the earth's lower atmosphere as a result of the increase in greenhouse gases since the Industrial Revolution. . The ice shelves-floating sheets of ice extending from the coast-are extremely sensitive to changing conditions and fall apart when temperatures rise above a critical point, report David G. Vaughan and Christopher S.M. Doake of the British Antarctic Survey Based in Cambridge, the British Antarctic Survey (BAS) is the United Kingdom's national Antarctic operator and has an active role in Antarctic affairs. BAS is part of the Natural Environment Research Council and has over 450 staff. in Cambridge, England. In the last 50 years, four ice shelves have collapsed along the Antarctic Peninsula Antarctic Peninsula, glaciated mountain region of W Antarctica, extending c.1,200 mi (1,930 km) N toward South America; in the south, volcanic peaks rise to c.11,000 ft (3,350 m). Most of its NE coast is fringed by the Larsen ice shelf. . At the same time, temperatures along the peninsula have climbed 2.5[degrees]161[degrees]C, a warming rate much faster than that seen in the rest of the continent. In the Jan. 25 Nature, Vaughan and Doake note that the ice shelves suffered when the mean annual temperature exceeded -5[degrees]161[degrees]C. This represents the limit for ice shelf existence, they claim. The scientists cannot say whether the recent Antarctic warmth is natural or a product of greenhouse gas pollution. If the trend continues, ice shelves closer to the pole will disintegrate, they predict. If conditions cool, though, ice shelves could regrow Re`grow´ v. i. & t. 1. To grow again. The snail had power to regrow them all [horns, tongue, etc.] - A. B. Buckley. Verb 1. . In the Feb. 9 Science, researchers from Austria and Argentina discuss the most recent collapse, which claimed part of the Larsen Ice Shelf Larsen Ice Shelf Ice shelf in the northwestern Weddell Sea, adjoining the eastern coast of the Antarctic Peninsula. It is named for Capt. Carl A. Larsen, who explored the ice front by boat in 1893. in January 1995. From this event, they conclude that ice shelves may retreat slowly at first and then fall apart rapidly after reaching a critical limit. |
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