Recent trends from Canadian Permafrost Thermal Monitoring Network Sites

The Geological Survey of Canada (GSC), in collaboration with other government partners, has been developing and maintaining a network of active-layer and permafrost thermal monitoring sites which contribute to the Canadian Permafrost Monitoring Network and the Global Terrestrial Network for Permafrost. Recent results from the thermal monitoring sites maintained by the GSC and other federal government agencies are presented. These results indicate that the response of permafrost temperature to recent climate change and variability varies across the Canadian permafrost region. Warming of shallow permafrost temperatures of between 0.3 and 0.6 degrees C per decade has occurred since the mid- to late 1980s in the central and northern Mackenzie region in response to a general increase in air temperature. No significant warming (less than 0.1 degrees C per decade) of permafrost is observed in the southern Mackenzie valley. Warming of shallow permafrost of between 1.0 and 4.0 degrees C per decade is also observed in the eastern and high Arctic, but this mainly occurred in the late 1990s. These trends in permafrost temperature are consistent with trends in air temperature observed since the 1970s. Local conditions however, influence the response of the permafrost thermal regime to these changes in air temperature. Copyright (c) 2005 John Wiley & Sons, Ltd.