Is the planet getting warmer? Scientists are trying to do the science around that question. Here's an article about warming and the Greenland Ice Sheet, from the San Francisco Chronicle.
From the article, "The vast ice cap that covers Greenland nearly three miles thick is melting faster than ever before on record, and the pace is speeding year by year, according to global climate watchers gathering data from twin satellites that probe the effects of warming on the huge northern island. The consequence is already evident in a small but ominous rise in sea levels around the world, a pace that is also accelerating, the scientists say. According to the scientists' data, Greenland's ice is melting at a rate three times faster than it was only five years ago. The estimate of the melting trend that has been observed for nearly a decade comes from a University of Texas team monitoring a satellite mission that measures changes in the Earth's gravity over the entire Greenland ice cap as the ice melts and the water flows down into the Arctic ocean...
"Next to Antarctica, Greenland, a self-governing Danish territory, is the largest reservoir of fresh water on Earth and holds about 10 percent of the world's supply. The increasing flow of fresh water -- most of it from glaciers melting on Greenland's eastern coast -- is already beginning to change the composition of the ocean's salt water currents flowing past Northwestern Europe, the scientists say. The result could be a critical change in the composition of the main ocean current that flows past Europe's northern edge, blocking off warmer waters that normally flow there and -- ironically -- making Northern Europe's weather colder than normal, at least temporarily, while the rest of the globe continues warming. The report on Greenland is being published today in the on-line edition of the journal Science by the University of Texas scientists at Austin, including Chen, aerospace engineer Byron Tapley and geologist Clark Wilson. According to the researchers, surface melting of Greenland's ice cap reached 57 cubic miles a year between April of 2002 and November of 2005, compared to about 19 cubic miles a year between 1997 and 2003...
"If the Greenland ice cap ever melted completely -- a highly unlikely event, at least in the foreseeable future -- the scientists estimate it would raise world's sea level by an average of 6.5 meters, or about 21 feet, more than enough to drown all the world's low-lying islands and even some entire nations, like Holland...
"Only last March two University of Colorado physicists used the same satellite system to measure melting of ice on the Antarctic continent. Although earlier evidence using other techniques appeared to show that the East Antarctica ice sheet was actually thickening, satellite data gathered by Isabella Velicogna and John Wahr at Boulder found that melting -- primarily from the West Antarctic Ice Sheet -- had turned at least 36 cubic miles of ice to fresh water each year from 2002 to 2005...
"Both the Texas and Colorado groups have been obtaining their data from two satellites known as GRACE, the Gravity Recovery and Climate Experiment, which fly in orbit 137 miles apart and determine with extraordinary accuracy just how the mass of even small regions of the Earth change as ice melts and flows away from the land to the sea. The GRACE satellite mission is due to end next year, but the Texas team is awaiting NASA approval for a new and improved satellite system to continue the work, using laser beams rather than microwaves to measure ice cap melting, Chen said."
"2008 pres"
5:41:07 AM 
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