Ice Shelf Breaking Apart
A narrow ice bridge connecting Charcot Island and Latady Island—the last remnant of the northern part of Antarctica’s Wilkins Ice Shelf—broke apart in early this month. Earth Observatory has some startling photo-like images, which show the break-up of the ice bridge.The ice bridge had been the last intact portion of the northern edge of the ice shelf. The southern portion of the Wilkins Ice Shelf is still intact, but may be more vulnerable now that the northern edge has disintegrated.
Real Climate has links to imagery from ESA (animation here) which show the recent story quite clearly and an active discussion in the comments is under way – about 400 comments to date.
“The rapid retreat of glaciers there demonstrates once again the profound effects our planet is already experiencing — more rapidly than previously known — as a consequence of climate change,” U.S. Interior Secretary Ken Salazar said in a statement.
“This continued and often significant glacier retreat is a wakeup call that change is happening … and we need to be prepared,” USGS glaciologist Jane Ferrigno, who led the Antarctica study, said in a statement. “Antarctica is of special interest because it holds an estimated 91 percent of the Earth’s glacier volume, and change anywhere in the ice sheet poses significant hazards to society,” she said.
However, possible more alarming, is the potential for resource rush that is likely to occur on lands and in waters that are now becoming accessible as a result of the dwindling ice cover. New evidence from NASA satellites released yesterday shows that the polar ice cap is shrinking in size and what’s left is thinner.
“Thickness is important, especially in winter, because it is the best overall indicator of the health of the ice cover,” research scientist Walter Meier of the National Snow and Ice Data Center in Boulder, Colo., said in announcing the findings. “As the ice cover in the Arctic grows thinner, it grows more vulnerable to melting in the summer,” a partial explanation for record melting in recent years.
The managers of Alaska’s fisheries agreed to forego any fishing in newly open Arctic waters to give scientists time to gauge the environmental impacts before exploiting a new resource. But the fishing fleets of other nations such as Norway have not waited, already following valuable fish stocks further north.
Meantime, Canada, Denmark, Norway, Russia, Sweden and the U.S. are all vying for sovereignty over large swathes of the Arctic that once were polar bear retreats but now are ice-free waters that contain oil and other fossil fuels as well as lucrative international shipping shortcuts. The newly open waters are good news for ships but presage starvation for polar bears, which is why they are now listed as an endangered species. Scientific American
