Studies predict increased sea level rise

Source Boston Globe

Two new scientific studies measuring Greenland's rapidly melting ice sheet and the pace of Antarctic snowfall suggest that the sea level may be rising faster than researchers previously assumed. The papers, both published on Aug. 17 in the journal Science, provide the latest evidence of how climate change is transforming the global landscape. One of the papers, written by 16 scientists from seven countries, challenges computer projections that warmer temperatures in the southernmost continent will spur greater snowfall accumulation and compensate for the world's melting ice sheets. Using satellite data that looked at both the West and East Antarctic ice sheets, the researchers concluded there has been no real increase in precipitation in the region in the last five decades. Previously, an increase in precipitation over Antarctica was predicted to thicken the ice sheets to counterbalance future melt. In a separate study, researchers determined that the Greenland ice sheet, the earth's second-largest reservoir of fresh water, is melting at a rate three times faster than during the previous five years. The ice loss along the sheet's eastern shoreline is particularly significant because it could help weaken the counterclockwise flow of the North Atlantic current. The more-buoyant fresh water from the ice melt could lower water temperatures and ultimately make Western European winters colder. Taken together, the two reports indicate that global sea level rise may increase more rapidly in the coming years. The predicted annual melting rate of 57 cubic miles a year from Greenland's ice sheet could increase the sea level by 0.6 millimeters alone, which is more than any previously published measurement for Greenland. For the past few hundred years, the sea level has increased an average of 1.8 millimeters annually.