The IPY Thermal State of Permafrost project– An unprecedented effort to assess permafrost temperature changes

During the planning and implementation of the International Polar Year the International Permafrost Association ( coordinated the acquisition of permafrost temperatures data under the Thermal State of Permafrost (TSP) Project #50. The TSP project goals were the acquisition of standardized temperature measurements (snapshot) from all permafrost regions of Planet Earth, preparation of a global data set, and development of maps of contemporary permafrost temperatures. Networks of boreholes, equipped for long-term permafrost temperature observations, were established and consist of approximately 850 boreholes in both hemispheres with more than 25 participating countries. More than 350 of these boreholes were drilled and instrumented during the IPY period under various nationally funded projects .

tsp_results_chartComparison of the current mean annual ground temperature (MAGT) and historical data allows participating countries and other users to assess changes in the thermal state of permafrost over the last several decades. A summary of borehole metadata information will be available online. The TSP project also included active layer measurements, many of which are observed annually under the Circumpolar Active Layer Monitoring (CALM) project. In the future, these networks will ideally continue and expand as part of an international network of permafrost observatories in both polar and non-polar permafrost regions and will provide links to national and international data resources.
Permafrost temperature records show that permafrost warming which started two to three decades ago has generally continued into the IPY period. Warming rates are much smaller for permafrost already at temperatures close to 0°C compared to colder permafrost, especially for ice-rich permafrost where latent heat effects dominate the ground thermal regime. Colder sites are generally warming more rapidly.

A special Issue of the journal Permafrost and Periglacial Processes (published June 8, 2010) presents the detailed results featured in this press release