Arctic sea ice melt threatens permafrost

BOULDER, Colo., June 12 (UPI) -- U.S. scientists say the rate of climate warming over northern Alaska, Canada, and Russia could more than triple during periods of rapid sea ice loss.

The findings of the study led by the National Center for Atmospheric Research raise concerns about the thawing of permafrost, or permanently frozen soil, and the potential consequences for sensitive ecosystems, human infrastructure, and the release of additional greenhouse gases.

"Our study suggests that, if sea-ice continues to contract rapidly over the next several years, Arctic land warming and permafrost thaw are likely to accelerate," said study lead author David Lawrence of NCAR.

The research was spurred in part by events last summer, when the extent of Arctic sea ice shrank to more than 30 percent below average, setting a modern-day record. From August to October last year, scientists said air temperatures over land in the western Arctic were also unusually warm, raising the question of whether the unusually low sea-ice extent and warm land temperatures were related.

The study by scientists from NCAR and the National Snow and Ice Data Center is to be published Friday in the journal Geophysical Research Letters.