Global warming could cool North America within a few decades.Byline: ANI Washington, September 15 (ANI): A new study has determined that 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. could actually chill down North America North America, third largest continent (1990 est. pop. 365,000,000), c.9,400,000 sq mi (24,346,000 sq km), the northern of the two continents of the Western Hemisphere. within a few decades. According to according to prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. a report in National Geographic News, the study, led by Tim Daley of Swansea University in the UK, looked into a sudden cooling event that gripped the North American North American named after North America. North American blastomycosis see North American blastomycosis. North American cattle tick see boophilusannulatus. region about 8,300 years ago. Analysis of ancient moss from Newfoundland, Canada, links an injection of freshwater from a burst glacial lake to a rapid drop in air temperatures by a few degrees Celsius along North America's East Coast. This event created a colder year-round climate with a much shorter growing season for about 150 years, from northern Canada to what is now Cape Hatteras, North Carolina North Carolina, state in the SE United States. It is bordered by the Atlantic Ocean (E), South Carolina and Georgia (S), Tennessee (W), and Virginia (N). Facts and Figures Area, 52,586 sq mi (136,198 sq km). Pop. . The results suggest that North America's climate is highly sensitive to meltwater melt·wa·ter n. Water that comes from melting snow or ice. meltwater Noun melted snow or ice Noun 1. flowing into the ocean, according to Daley. The work also means that history could repeat itself. Currently, Greenland's ice sheet is melting at a rapid clip, releasing freshwater into the North Atlantic. Daley and colleagues studied mosses dating back more than 8,700 years that were preserved in a Newfoundland peat bog. The ratios of two different types of oxygen in the mosses allowed the team to trace changes in atmospheric temperature over time. When air temperatures are lower, the mosses contain less oxygen-18, a heavier version of the more common type, oxygen-16. About 8,350 years ago, the amount of oxygen-18 relative to oxygen-16 suddenly dropped. Previous research had found that, around the same time, a northern ice dam burst, releasing the contents of a vast glacial lake into the Labrador Sea, between Canada and Denmark. Normally, a warm ocean current called the Gulf Stream runs up the east coast of North America, helping to keep the region balmier than it should be, considering how far north it is. But, the entire glacial lake drained within less than a year, injecting a huge pulse of freshwater into the North Atlantic Ocean North Atlantic Ocean The northern part of the Atlantic Ocean, extending northward from the equator to the Arctic Ocean. . According to Daley and colleagues, the lake water diluted the salty ocean current and slowed the Gulf Stream, which in turn led to rapid cooling in North America. "As a result, Canadian summer temperatures would have been similar to those currently experienced in autumn or spring," said team member Neil Loader, also of Swansea University. As for whether today's melt in Greenland could trigger another round of cooling, Hans Renssen, a climate researcher at Vrije University in Amsterdam, said that he doesn't believe the change would be as dramatic as last time. (ANI) Copyright 2009 Asian News International The Asian News International (ANI) agency provides multimedia news to China and 50 bureaus in India. It covers virtually all of South Asia since its foundation and presently claims, on its official website, to be the leading South Asia-wide news agency. (ANI) - All Rights Reserved. Provided by Syndigate.info an Albawaba.com company |
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