Data Set ID:

Arctic and Southern Ocean Sea Ice Concentrations, Version 1

This data set provides monthly sea ice concentration for the Arctic from 1901 to 1995 and for the Southern Oceans from 1973 to 1990 on a standard 1-degree grid (cylindrical projection) to provide a relatively uniform set of sea ice extent for all longitudes. The data are in ASCII format and are available via FTP.

This is the most recent version of these data.

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Data: Data integrity and usability verified

Documentation: Key metadata and user guide available

User Support: Assistance with data access and usage; guidance on use of data in tools

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Data Format(s):
Spatial Coverage:
N: 90, 
N: -50, 
S: 40, 
S: -90, 
E: 180, 
E: 180, 
W: -180
W: -180
Platform(s):DMSP 5D-2/F11, DMSP 5D-2/F8, GROUND-BASED OBSERVATIONS, Nimbus-7
Spatial Resolution:
  • 1 degree x 1 degree
Temporal Coverage:
  • 1 January 1953 to 31 August 1995
(updated 1996)
Temporal Resolution1 monthMetadata XML:View Metadata Record
Data Contributor(s):John Walsh, William Chapman

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.

Chapman, W. L. and J. E. Walsh. 1991, updated 1996. Arctic and Southern Ocean Sea Ice Concentrations, Version 1. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: [Date Accessed].

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