Recently Eli Rabett has reported on the opening of the Northwest Passage, a sea route for ships to travel from Europe to Asia via north of Canada. The Washington Post is reporting that the recent ice melt is unprecedented:
According to the National Snow and Ice Data Center at the University of Colorado at Boulder, September sea ice was 39 percent below the long-term average from 1979 to 2000. Sea ice cover is in a downward spiral and may have passed the point of no return, with a possible ice-free Arctic Ocean by summer 2030, senior scientist Mark Serreze said.Clearly records are being broken. But one thing that has flown under the radar of most of the climate blogs is *why* this is important to those concerned about climate change.
#1 Predictions & Rate of Change
The first reason why this is important is the rate of change:
Deborah Williams _ who was an Interior Department special assistant for Alaska under former President Bill Clinton, and who is now president of the nonprofit Alaska Conservation Solutions _ said melting of sea ice and its effects on wildlife were never even discussed during her federal service from 1995 to 2000.In other words all of the worst case scenario predictions made pre-2000 have underestimated the impacts of Anthropogenic Climate Change. This stands in stark contrast from the "fear monger" name calling coming out of the CFC's-don't-harm-ozone and Exxon funded Heartland Institute.
"That's what so breathtaking about this," she said. "This has all happened faster than anyone could have predicted.
#2 Loss of Habitat
The second reason sea ice melt is important is was reported on yesterday in the Washington Post. Walruses are normally "spread over thousands of miles of sea ice" so they can dive down to eat clams, snails and other bottom dwellers. Floating ice is the perfect hunting ground for walruses as it act like a moving conveyor belt allowing them to rest between dives and catch lots of food. Yet the ice has receded to water deeper than their 630 foot diving range and so their natural habitat has literally disappeared. Now the thousands of walrus have picked Alaska's rocky beaches. The walrus has lost thousands of miles of hunting grounds, a natural conveyor belt of food and are not collected in one tiny spot. Clearly things are going to get rather uncomfortable for the walrus.
The third, and possibly most important, reason why ice melt is important is the albedo effect. Ice acts like a mirror and shines light back into space. When this ice is gone the ocean will absorb quit a bit more light. The effect is rather strong and during the ice ages the albedo effect was calculated to account for 2/3's of the cooling while CO2 was only 1/3. Melting ice can be a massive positive feedback for global warming.
Of course climate critics like Lubos Motl are praising this as a "Nature's gift". And so the debate starts to exit a scientific field and starts to enter a moral one.