Warm ocean delays sea ice

Warming trend affects people, wildlife, coastline

ANCHORAGE, Alaska — The U.S. research vessel Sikuliaq can break through ice as thick as 2.5 feet. In the Chukchi Sea northwest of Alaska this month, which should be brimming with floes, its limits likely won’t be tested.

University of Washington researchers left Nome on Nov. 7 on the 261-foot ship, crossed through the Bering Strait and will record observations at multiple sites including Utqiagvik, formerly Barrow, America’s northernmost community. Sea ice is creeping toward the city from the east in the Beaufort Sea, but to find sea ice in the Chukchi, the Sikuliaq would have to head northwest for about 200 miles.

In the new reality of the U.S. Arctic, open water is the November norm for the Chukchi. Instead of thick, years-old ice, researchers are studying waves and how they may pummel the northern Alaska coastline.

“We’re trying to understand what the new autumn looks like in the Arctic,” said Jim Thomson, an oceanographer at the UW Applied Physics Laboratory.

Sea ice in the Chukchi Sea every day since mid-October has been the lowest on record, said Rick Thoman, a climate expert at the University of Alaska Fairbanks’ International Arctic Research Center.

Low ice is a problem for people of the coast. Communities north and south of the Bering Strait rely on near-shore ice to act as a natural sea wall, protecting land from erosion brought on by winter storms.

Sea ice is a platform from which to catch crab or cod in Nome, a transportation corridor between villages in Kotzebue Sound and a work station on which to butcher walrus near Gambell.

Sea ice creates structure in the water column that separates Arctic species from commercially valuable fish such as Pacific cod and walleye pollock.

And then there’s wildlife. Sea ice is the prime habitat for polar bears and the preferred location for dens where females give birth. Female walruses with young use sea ice as a resting platform and follow the ice edge south as it moves into the Bering Sea.

Thomson and other scientists on the Sikuliaq will look at how climate changes could affect coastlines, which already are eroding. Less ice and more open water translate to a significant threat. Ice acts as a smothering blanket, keeping down the size of waves. Open water increases fetch, the distance over which wave-generating winds blow.

“We know from other projects and other work that the waves are definitely on the increase in the Arctic,” Thomson said.

That means even more erosion, the chance of winter flooding in villages and increased danger to hunters in small boats.