Permafrost temperatures have warmed as much as 2°C from 20 to 30 years ago
Fairbanks, Alaska — Permafrost warming continues throughout a wide swath of the Northern Hemisphere, according to a team of scientists assembled during the recent International Polar Year.
Their extensive findings, published in the April-June 2010 edition of Permafrost and Periglacial Processes, describe the thermal state of high-latitude permafrost during the International Polar Year, 2007-2009. Vladimir Romanovsky, a professor with the snow, ice and permafrost group at the University of Alaska Fairbanks Geophysical Institute, is the lead author of the paper, which also details the significant expansion of Northern Hemisphere permafrost monitoring. “This paper is actually pretty unique,” Romanovsky said, “because it’s the first time such a large geographical area has been involved in one paper.” During the International Polar Year, Romanovsky and his colleagues launched a field campaign to improve the existing permafrost-monitoring network. The permafrost thermal state is monitored with borehole sensors, which gather data from holes drilled deep into the permafrost. The researchers established nearly 300 borehole sites that serve as permafrost observatories across the polar and sub-polar regions in the Northern Hemisphere. Their work more than doubled the size of the previously existing network “The heart of monitoring is the measuring of temperatures in boreholes,” Romanovsky said. “For permafrost temperatures, you have to be there. You have to establish boreholes.” Having data from across the circumpolar North allows scientists to analyze trends affecting permafrost. The article notes that permafrost temperatures have warmed as much as two degrees Celsius from 20 to 30 years ago. They also found that permafrost near zero degrees Celsius warmed more slowly than colder permafrost. According to Romanovsky, this trend is an example of the large-scale analysis possible using data from the expanded network. …
