Limits of Permafrost in Northern Canada Pushed Back over 130 km in last 50 Years
18.02.2010 - Land & Geology, Ice & Snow, Arctic
Over the course of the past 50 years, the limits of permafrost in the James Bay region of Canada have moved northwards by 130 kilometers, according to researchers from the Université Laval. A study, published in the scientific journal Permafrost and Periglacial Processes, their research suggests that permafrost in the region might completely disappear in the near future.
By observing palsas, oval elevations which form naturally over ice contained in the soil of northern peat bogs, the researchers were able to conclude arrive at the conclusion that permafrost is retreating. In 2004, their initial survey of seven bogs showed only two of them to contain palsas, whereas aerial photos from 1957 showed palsas present in all of the bogs. A second assessment in 2005 showed that the presence of palsas in these two bogs had decreased by 86% and 90% respectively in one single year.
Although climate change can probably be held responsible for the phenomenon, the lack of long term climatic data for the area prevents any scientific confirmation.
