re: tuvalu soon:gold coast next
It isn't my calculation, jar-jar. It is the calculation for the IPCC report. Now if the calculation were dodgy it would be a part of the skeptics liturgy. As it is, the skeptics can only use the "continental rise will offset sea level rise" argument sporadically. The worrying thing about the ice sheet studies is the early inference that they are melting far faster than predicted.
A recent report from the Intergovernmental Panel on Climate Change -- known as the IPCC -- estimated that during all of the past century worldwide melting ice from global warming had raised sea levels by only two-tenths of a millimeter a year, or about 20 inches[sic] for the entire century.
But, according to Chen and his Texas team, the melting of Greenland's ice cap is already raising global sea levels by six-tenths of a millimeter each year, and the Colorado group estimates that melting of the West Antarctic Ice Sheet alone is adding up to four-tenths of a millimeter of fresh water to sea levels each year. In other words, the global sea level, due to melting of the ice in Greenland and Antarctica combined, is already rising 10 times faster than the IPPC's tentative estimates, the two analyses indicate.
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.
In a recent summary of the ice cap melting problem and its effect on sea levels reported by Richard Kerr in Science, geoscientist Michael Oppenheimer of Princeton said, "The time scale for future loss of most of an ice sheet may not be millennia," as glacier models have suggested, "but centuries."
