The International Permafrost Association releases the IPA-IPY Thermal State of Permafrost (TSP) Snapshot Borehole Inventory, the first comprehensive global inventory of permafrost temperatures as an output of the International Polar Year

During the planning and implementation of the International Polar Year (IPY) 2007 - 2009, the International Permafrost Association (IPA) coordinated the acquisition of permafrost temperature data under the TherIPA_TSP_Arctic_and_Antarctimal State of Permafrost (TSP) Project #50. The TSP project goals included the acquisition of standardized temperature measurements (snapshots) from all permafrost regions on Earth, preparation of a global data set, and development of maps of contemporary permafrost temperatures. As a result of the project, networks of boreholes, equipped for long-term permafrost temperature observations, were established and consist of approximately 860 boreholes in both hemispheres with more than 25 participating countries. Approximately 350 of the boreholes were drilled and instrumented during the IPY period under various nationally funded projects. Comparison of the current Mean Annual Ground Temperature (MAGT) and historical data allows participating countries and other users to assess the thermal state of permafrost dynamics over the last several decades. The TSP project also included active layer measurements, many of which are observed annually under the Circumpolar Active Layer Monitoring (CALM) project. The TSP is a field component of the Global Terrestrial Network for Permafrost (

The National Snow and Ice Data Center prepared the metadata and posted the data set on its web site:

Data from over 500 of these boreholes were presented and discussed in a series of papers in the special IPY - TSP issue of Permafrost and Periglacial Processes ( that include five regional papers and one synthesis paper. The main Data Contributors of this data set were senior authors of these papers.

The TSP Snapshot Inventory was compiled and edited from individual sources by Alexander Kholodov, Permafrost Laboratory, Geophysical Institute, University of Alaska Fairbanks, and Jerry Brown, President (2003-2008), International Permafrost Association.


Jerry Brown (
Vladimir Romanovsky (
Sharon Smith (
Hanne Christiansen (
Goncalo Vieira (

Web links:

TSP metadata record: (
International Permafrost Association (