Global Annual Freezing and Thawing Indices, Version 1
Data set id:
NSIDC-0063
DOI: 10.5067/TT6J3BH5YSSR
This is the most recent version of these data.

Overview

The total annual freezing and thawing indices are defined as the cumulative number of degree-days when air temperatures are below and above zero degrees Celsius. The total annual freezing index has been widely used to predict permafrost distribution; estimate the maximum thickness of sea, lake, and river ice, and the maximum depth of ground-frost penetration; and classify snow types. The annual total thawing index has been used to predict permafrost distribution and to estimate the maximum depth of thaw in frozen ground. Both total freezing and thawing indices are important parameters for engineering design in cold regions. Data coverage is global. The data set contains the total annual freezing and thawing indices with a spatial resolution of 0.5 degrees latitude by 0.5 degrees longitude. Two data files are available, for the freeze and thaw indices respectively, in flat binary format. Each file is approximately 1 MB in size. The total annual freezing and thawing indexes were calculated based upon the monthly mean air temperature by Legates and Willmott (1990).
Parameter(s):
AIR TEMPERATUREFREEZE/THAWPERMAFROST
Platform(s):
GROUND STATIONS
Sensor(s):
THERMOMETERS
Data Format(s):
Not Specified
Temporal Coverage:
1 January 1920 to 31 December 1980
Temporal Resolution:
  • 1 year
Spatial Resolution:
  • Not Specified
Spatial Coverage:
N:
90
S:
-90
E:
180
W:
-180
Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.

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