Sea levels have been rising for the past few decades, most due to global warming which is caused by the production of greenhouse gases, as we all already know. On average, the oceans are about 6.3 inches higher now than they were in 1930. The main cause is the expansion and therefore warming of sea water, from the melting caps and glaciers.
A new study has shown that reservoirs play an important role in the sea levels rising. Rather than adding to the problem, they are reversing it by storing more water on land. Reservoirs have prevented a total of about 1.2 inches of seal level rise since 1930. Without dams, the ocean would be 30 percent higher than it is today, according to a researcher from the National Central University of Taiwan.
Researchers tallied up the water stored behind the nearly 30,000 dams built worldwide. It was estimated that human-made reservoirs can store on average about 2,600 cubic miles of water. That’s nearly as much as Lake Superior holds. The water underneath the reservoirs also soaks into the ground, adding to the amount of water locked up on land.
http://news.nationalgeographic.com/news/2008/03/080313-dams-water.html
Greenland and Antarctica together comprise nearly 99 percent of the earth’s landlocked ice. These two polar landmasses contain enough frozen water to raise sea levels some 80 meters. Even if only 10 percent of this ice melted, it would flood the world’s coasts at those comparable to those seen in pos-Katrina New Orleans. A scenario that glaciologist and climate scientists are piecing together is that rather than slowly but steadily melting, the ice sheets could break apart into massive chunks.
http://www.dailygalaxy.com/my_weblog/2008/01/global-warming.html
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