www.csua.org/u/i1z -> news.nationalgeographic.com/news/2004/11/1109_041109_polar_ice.html
May Swamp US Coasts by 2099 Brian Handwerk for National Geographic News November 9, 2004 Scientists have determined that the ice in Greenland and the Arctic is melting so rapidly that much of it could be gone by the end of the century.
Freshwater Runoff Into Arctic on the Rise, Scientists Say The Arctic Climate Impact Assessment was released yesterday. It will be discussed by the Arctic Council (the governments of Canada, Denmark, Finland, Iceland, Norway, the Russian Federation, Sweden, and the US, as well as six indigenous-peoples organizations) at a meeting in Iceland today. The four-year study of the Arctic climate involved an international team of more than 300 scientists. They used a number of climate models and made a "moderate estimate" of future emissions of carbon dioxide and other greenhouse gases that are widely believed to be contributing to the recent warming trend of the Earth's climate. The study concluded that in Alaska, western Canada, and eastern Russia, average temperatures have increased as much as 4 to 7 degrees Fahrenheit (3 to 4 degrees Celsius) in the past 50 years, nearly twice the global average. Temperatures are projected to rise 7 to 13 degrees Fahrenheit (4 to 7 degrees Celsius) over the next hundred years. The rising temperatures are likely to cause the melting of at least half the Arctic sea ice by the end of the century. A significant portion of the Greenland ice sheet--which contains enough water to raise the worldwide sea level by about 23 feet (about 7 meters)--would also melt. The consequences of such a massive meltdown of northern ice would be dramatic, according to the study. Low-lying coastal areas in Florida and Louisiana could be flooded by the sea. A 15 feet (50-centimeter) rise in sea level could cause the coastline to move 150 feet (45 meters) inland, resulting in substantial economic, social, and environmental impact in low-lying areas. The health and food security of some indigenous peoples would be threatened, challenging the survival of some cultures. Should the Arctic become ice-free in summer, it is likely that polar bears and some seal species would become extinct. The melting of so much ice, and the resulting addition of so much fresh water to the ocean, could impact the circulation of currents and affect regional climate.
More Photos in the News Arctic ice melting Computer models project how the Arctic ice cap may melt over the next century. The blue perimeter (marked by arrows) is actual ice in September 2002. The top illustration projects how the ice may shrink by 2030, the middle shows what may be left by 2060, and the bottom indicates what it could look like in 2090. Some computer models project all the ice will be gone within a century. A combination of computer models indicates that at least half of today's ice cover will have melted within a hundred years.
Download as Wallpaper MORE INFORMATION Warming to Cause Catastrophic Rise in Sea Level? Most scientists agree that global warming presents the greatest threat to the environment. In the last century the average temperature has climbed about 06 degrees Celsius (about 1 degree Fahrenheit) around the world. From the melting of the ice cap on Mount Kilimanjaro, Africa's tallest peak, to the loss of coral reefs as oceans become warmer, the effects of global warming are often clear. However, the biggest danger, many experts warn, is that global warming will cause sea levels to rise dramatically. Thermal expansion has already raised the oceans 4 to 8 inches (10 to 20 centimeters). But that's nothing compared to what would happen if, for example, Greenland's massive ice sheet were to melt. Using computer models, scientists have created a series of maps that show areas susceptible to rises in sea level. One map shows that a 6-meter (20-foot) rise would swamp Miami, Fort Lauderdale, Tampa, and the entire Florida coastline, in addition to parts of Orlando and other inland areas. "The consequences would be catastrophic," said Jonathan Overpeck, director of the Institute for the Study of Planet Earth at the University of Arizona in Tucson. "Even with a small sea level rise, we're going to destroy whole nations and their cultures that have existed for thousands of years."
|
http://csua.com/feed/