Tuesday, October 4, 2011

Climate Change and the Exodus of Species

To most humans, so far, climate change is still more of an idea than an experience. For other species, it is an immediate reality. Many will be left behind as the climate alters, unable to move quickly enough or with nowhere to move to. Others are already adapting. An iconic example of these swift changes is the recent discovery that Atlantic and Pacific populations of bowhead whales — long kept apart by the frozen Arctic — are now overlapping in the open waters of the Northwest Passage.

A team of scientists from the University of York examined the movement of 2,000 animal and plant species over the past decade. According to their study, published in Science last month, in their exodus from increasing heat, species have moved, on average, 13.3 yards higher in altitude — twice the predicted rate — and 11 miles higher in latitude — three times faster than expected. These changes have happened most rapidly where the climate has warmed the most.

Chris Thomas, an author of the study, says, these changes “are equivalent to animals and plants shifting away from the equator at around 20 centimeters per hour” for the past 40 years. This rate will increase as the pace of climate change increases, bringing with it rapid adaptation but also a rate of extinction and a loss of genetic diversity surpassing anything the fossil record shows us.

A rapid reduction in greenhouse gas emissions is tragically unlikely. We are holding the future of every species on this planet — including ourselves — hostage.