THERMAP Overview

The Thermap collection has moved to the U.S. Antarctic Program Data Center (USAP-DC), available through the 10-meter-depth ice temperature and shallow firn temperature data products. Effective February 8, 2021, these data products will no longer be available from NSIDC.
Ellsworth Highland Traverse Ellsworth Highland Traverse Crew 1960-1961
Ellsworth Highland Traverse Crew 1960-1961
Photo Courtesy of: NOAA Photo Library

The THERMAP data set is a combination of Antarctic ice sheet subsurface temperature measurements. The measurement types are: shallow firn core temperatures (10-meter temperatures), deeper ice core temperatures (drill hole temperatures), and shallow firn temperature records (shallow firn annual cycle temperature measurements). The 10-meter temperature measurements provide a close estimate of mean annual surface air temperature. The deeper drill-hole temperatures reveal basal phase states (frozen or thawed), geothermal heat flow, and the thermal and dynamic history of the ice. Shallow firn temperature records show temperature fluctuations at various depths. Data come from a variety of published and unpublished sources.

The 10-meter data contains temperature measurements dating back prior to 1956 and the International Geophysical Year, including measurements from several major recent surveys. Data cover the entire continental ice sheet and several ice shelves, but coverage density is generally low. For more information, please see the notes available for each 10-meter data set, and the list of related publications. The deeper drill-hole temperature data collection also covers a large portion of the ice sheet. The time frame covered by this collection is 1949-1979.

Shallow firn temperature records include year-round temperature measurements made at various sites around the continent. Depths of measurements range from the surface to as deep as 16m, on intervals of 0.5m to 8m. Time intervals of measurements vary from one day to one month. Most of these measurements were collected around the International Geophysical Year (1957-58).

The data are stored in ASCII tables. Along with each data set are location information (latitude and longitude, and in some cases approximate elevation), date of acquisition, data source, and closely related data such as snow or ice density and accumulation rate.

Please read the accompanying documentation before working with these data. A complete list of data set sources is included in this documentation.