by Kassie Siegel, Climate Prog. Dir, Center for Biological Diversity
Since early August I have been riveted by the National Snow and Ice Data Center's near weekly updates on Arctic sea ice. On August 17, sea ice extent dropped below the previous record low in September 2005 of 5.05 million square miles. As of September 4, sea ice extent had fallen to 4.75 million square miles, fully 250,000 square miles below the previous record low, and the melting is expected to continue into the third week in September.
The status of distant Arctic sea ice is important to all of us for a number of reasons. The sea ice is the basis of an entire ecosystem now at risk of disappearing entirely. The polar bear, the Arctic's top predator, and an icon of the far North, is now the symbol of rapid global warming. Polar bears rely upon the sea ice for all of their essential behaviors, and cannot survive the loss of their habitat. They are indeed already drowning, starving, and resorting to cannibalism due to the loss of sea ice, and will become extinct unless we can slow the warming and stabilize the climate system through deep greenhouse gas reductions.
The Arctic sea ice is also important because it is part of one of the climate system's major feedback loops having to do with the reflectivity of the Earth's surface. Snow and ice reflect about 90% of incoming solar energy back into space, while open water absorbs about 90% of this same energy. Thus, as sea ice declines, Arctic warming accelerates. While melting of sea ice does not substantially contribute to sea level rise, the vicious cycle of additional warming certainly does impact the melting of the land-based ice of Greenland. Melting of the Greenland ice sheet has also accelerated far beyond scientists' projections. If the Greenland ice sheet melts entirely, sea level will rise by about 20 feet. Leading scientists warn that just ten more years of continued greenhouse gas emissions increases will commit us to this amount of sea level rise, as well as the extinction of about a third of the planet's plants and animals.
All of this is indeed horrifying, but it is not cause for despair, but rather a call to action. The good news is that there is still time to save the Arctic, though the window is closing. Our hope lies in a rapid response including both deep and immediate carbon dioxide reductions, as well as a full-court press on other greenhouse pollutants such as methane. While carbon dioxide emissions remain in the atmosphere for about a century, and therefore commit us to long term warming, methane is more powerful but remains for only about a decade. Opportunities to reduce methane from sources like landfills, mining, and agriculture abound, and such reductions would also directly benefit air quality and human health. With such reductions we can still buy ourselves some time.
But we cannot "stay the course" of our current energy consumption, land use, and transportation patterns, without losing the Arctic sea ice, polar bears, and the quality of life we have enjoyed. We must reduce greenhouse gas pollution to a very small fraction of today's levels in the next few decades. We must collectively rise to the challenge. If you are appalled by the current loss of sea ice in the Arctic, take action starting today. Make changes in your own life to reduce your greenhouse gas footprint, but most importantly, hold your elected officials accountable for enacting a solution -immediate mandatory regulation and reduction of greenhouse gas pollution.
For more information, visit
http://www.biologicaldiversity.org">BiologicalDiversity.org