'Triple Whammy' Erodes Alaskan Coasts

Geologists and climatologists have been aware that global warming and climate change have been eroding the Alaskan coastline for many years, but they have been unsure of the extent of the damage until recently. After using a camera to snap a series of time-lapse photos, they are now able to conclude that the Alaskan coast is receding by as much as 45 feet (14 meters) annually. The team behind the new investigation also identified three main causes for the erosion – declining levels of sea ice, warming oceanic waters, and more intense wave action caused by the former two, LiveScience reports.

The group says that the area between Point Barrow and Prudhoe Bay is the most affected with almost a third of a football field's worth of land falling into the ocean each year. Erosion rates are also higher than for most other coastlines around the planet, the scientists say. “This is pretty eye-popping,” University of Colorado in Boulder (UCB) expert Robert Anderson said yesterday during a speech he made at the annual meeting of the American Geophysical Union.

He and his team say that, in some areas, the time-lapse photos show how the warming waters simply eat away at the frozen blocks of silt and peat making up the soil. These blocks are 50 to 80 percent water-ice, so the warmer water has a devastating effect on them. One of the main reasons for this is the fact that the Beaufort sea is constantly losing ice, which allows for more warm water to endure during the summer months. Experts estimate that about two more weeks of warm water are added to the annual mean each decade.

“What we are seeing now is a triple whammy effect. Since the summer Arctic sea ice cover continues to decline and Arctic air and sea temperatures continue to rise, we really don't see any prospect for this process ending. The landscape is beginning to respond to the acceleration of warming,” Anderson added. The area currently most affected also hosts bird habitats, as well as a host of deserted military and oil installations, which could be submerged in a few years. They could release potent toxins into the water, further threatening the various species of aquatic animals living in the area.