ANCHORAGE, – A portion of Alaska’s North Slope coastline is eroding at a rate of up to 45 feet a year, posing a threat to oil operations and wildlife in the area, according to a new report issued by scientists at the University of Colorado.

Warmer ocean water has thawed the base of frozen bluffs and destroyed natural ice barriers protecting the coast, causing large earth chunks to fall each summer, the scientists said.

“What we are seeing now is a triple whammy effect,” study co-author Robert Anderson, an associate professor at the University of Colorado’s Department of Geological Sciences, said. “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 scientists studied coastline midway between Point Barrow, the nation’s northernmost spot, and Prudhoe Bay, site of the nation’s biggest oil fields. The erosion, if it continues, could ultimately be a problem for energy companies such as Exxon Mobil Corp and BP Plc.

“The northern coastline of Alaska midway between Point Barrow and Prudhoe Bay is eroding by up to one-third the length of a football field annually because of a “triple whammy” of declining sea ice, warming seawater and increased wave activity, according to new study led by the University of Colorado at Boulder.”

See more on the story here from the University of Colorado.

Findings were presented last week at the annual meeting of the American Geophysical Union in San Francisco. They backed up other studies of erosion along Alaska’s Beaufort Sea coastline.

A study by U.S. Geological Survey scientists published in February found that erosion along a stretch of Alaska coastline during 2002 to 2007 was twice as fast as in the period from 1955 to 1979. That USGS study also found erosion occurring at a rate of 13.6 meters (44.6 feet) annually from 2002 to 2007.

The three-year University of Colorado study aimed to examine how erosion is occurring, said co-author Irina Overeem, a scientist at the University’s Institute of Arctic and Alpine Research.

The scientists employed time-lapse photography, global positioning systems, meteorological monitoring, and analysis of sediment and sea-ice distribution.

Photographic images snapped every six hours during the around-the-clock sunlight of summer were particularly dramatic, Overeem told Reuters.

“There’s a notching effect that just notches, notches, notches and then topples over,” she said. “The cliffs are more than half ice — they’re basically dirty icebergs — so warm water, stronger waves and higher wave action quickly carves them away,” she said.

Read more here.

 

(Editing by Bill Rigby, Gary Hill)

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