Wednesday, November 9, 2011

Bering Sea storm: Has global warming made Alaska more vulnerable?

Bering Sea storm winds are lashing the coast of Alaska. Sea ice extending out from the shoreline has protected the coast from past Bering Sea storm surges, but there is little such ice this year, and global warming is likely to blame.

A powerful fall storm – the strongest since a mid-November storm in 1974 – is pounding Alaska's west coast with hurricane-force winds and a storm surge that in many places is expected to top eight feet above the high-tide line. Although Alaska's coast is sparsely populated compared with other coastal regions in the US, low-lying areas host a number of native Alaskan villages, as well as the city of Nome.
Concerns for flooding and coastal erosion are compounded by a lack of coastal sea ice, which typically extends from the shoreline out toward the open ocean and is building at this time of year. "There's not a lot of shore-fast ice yet," says Scott Berg, a meteorologist with the National Weather Service forecast office in Fairbanks. "This year it hasn't developed quite as extensively as it normally does."

This shore-fast ice, which builds in bays along the coast north of Nome, typically represents a first line of defense against coastal flooding when storms plow into the state's coastline. It reduces storm surge. More