14 December 2009

DISAPPEARING ACT




Only it's not an act, it is all too real. Just as the namesake glaciers in Glacier National Park are fast disappearing in both number and size, the Arctic ice cap is shrinking at an alarming rate. You don't have to take my word for it -- simply compare the NASA photos taken in 1979 (above) and in 2007 (below). According to 350.org, an organization devoted to public education and action on global warming, the Arctic will be completely free of ice during the summer between 2011 and 2015, some eighty years earlier than scientists had previously predicted. 350.org and other efforts are the brainchildren of Bill McKibben, an American environmentalist and writer.

The disappearance of Arctic ice has global climate consequences, most directly in the removal of its regulatory effect on the circulatory currents of the world's oceans. Arctic ice forms both a temperature and salinity buffer, as well as a physical barrier defining current patterns (for example, the gyre formed by the Gulf Stream, the North Atlantic Drift, and the North Equatorial currents in the Atlantic Ocean). Altering ocean current paths, temperatures and salinity will have inevitable ripple effects on all life forms in or near the ocean. Including humans.

None of this is news to those of us who've studied the environment for any length of time. I received my bachelor's degree in Ecology & Evolutionary Biology over twenty years ago, and these events were already being discussed. We have already pushed the planet past numerous thresholds, and even with the best of intentions and overnight cooperation between all governments and all peoples, an inexorable momentum of change has been established, which it will take decades (if not centuries) to stabilize, then reverse. The question in my mind is this: how many ecosystems and species (including our own) have we doomed by our own myopia?

Special thanks to my friend and correspondent J, who turned me on to the 350.org website.









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