Data Set ID:

Northern Hemisphere EASE-Grid Annual Freezing and Thawing Indices, 1901 - 2002, Version 1

This data set contains annual freezing and thawing indices for each year from 1901 to 2002 on the 25 km resolution Equal-Area Scalable Earth Grid (EASE-Grid). Annual freezing and thawing indices are defined as the cumulative number of degree-days when air temperatures are below and above 0 degrees C. The values were calculated based upon the monthly mean air temperature from the 1901-2002, 0.5 deg. global land temperatures from the University of East Anglia Climate Research Unit (Mitchell and Jones, 2005).

Two ASCII files are available for each year for the freezing and thawing indices, respectively. Each file is approximately 5.5 MB in size. In addition, there is one 10.4 MB ASCII file defining the latitude and longitude coordinates for each grid point. The data set is available in compressed form via FTP.

This is the most recent version of these data.

BASIC Level of Service

Data: Data integrity verified

Documentation: Key metadata and links to supporting documentation available

User Support: Assistance with data access and basic data usage

See All Level of Service Details

  • Atmospheric Temperature > Air Temperature > AIR TEMPERATURE
  • Atmospheric Temperature > Degree Days > Freezing/Thawing Index
  • Atmospheric Temperature > Surface Air Temperature
Data Format(s):
Spatial Coverage:
N: 90, 
S: 0, 
E: 180, 
W: -180
Platform(s):Not specified
Spatial Resolution:
  • 25 km x 25 km
Sensor(s):Not specified
Temporal Coverage:
  • 1 January 1901 to 31 December 2002
Temporal Resolution1 yearMetadata XML:View Metadata Record
Data Contributor(s):Tingjun Zhang, Oliver Frauenfeld, R. Barry

Geographic Coverage

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As a condition of using these data, you must cite the use of this data set using the following citation. For more information, see our Use and Copyright Web page.

T. Zhang, O. W. Frauenfeld, James McCreight, Roger Barry 2005. Northern Hemisphere EASE-Grid Annual Freezing and Thawing Indices, 1901 - 2002, Version 1. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: [Date Accessed].

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