Alaska's largest city sets high-temperature record

Three Alaska locations including the state's largest city reached record-high temperatures on Independence Day, which an expert on Friday attributed to climate change.

"It's a weather story and it is an ongoing changing environment story as well as these kinds of extreme weather events become much more likely in a warming world," said Rick Thoman, a climate specialist at the University of Alaska Fairbanks' Alaska Center for Climate Assessment and Policy.

Anchorage on Thursday afternoon climbed to 32.2 Cfor the first time at Ted Stevens Anchorage International Airport, the officialmonitoring station.

The previous high for Anchorage was 29.4 Con June 14, 1969, said National Weather Service meteorologist Bob Clay. The average high temperature for July 4 is 23.8C, Clay said.

Kenai and King Salmon also reached new high temperatures of 31.6C. Palmer matched its record at 31.1 C.

High-pressure ridge responsible

A high-pressure ridge over much of south-central Alaska is strengthening and responsible for the record temperatures, Clay said.

The current high-pressure system comes on top of previous warming and high ocean temperatures, he said.

"Surface temperatures are above normal everywhere around Alaska," Thoman said. "The entire Gulf of Alaska, in the Bering Sea, in the Chukchi Sea south of the ice edge, exceptionally warm waters, warmest on record, and of course record-low sea ice extent for this time of year off the north and northwest coasts of the state."

Storms could mix warm surface water with cooler waters in lower portions of the upper ocean, he said, but storminess is at a minimum this time of year.

"Certainly, for instance, above-normal temperatures in Cook Inlet right now are contributing to the very warm temperature that are being reported from Anchorage International," Thoman said.

"If it had been a cold spring and a cool June and water temperatures were cooler, exactly the same kind of atmosphere pattern may well not produce record temperatures."