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Data Set ID:

GLERL Great Lakes Ice Concentration Data Base, 1960-1979, Version 1

Ice concentration grids for 1960 to 1979 are archived for half-month periods, generally December through April. Data values are coded to the nearest ten percent for each 5 x 5 km grid square. A file of geographic coordinates of the center of each grid cell is included for each lake. A file of ice climatology data for each lake includes average, median and mode for each grid cell for each half-month period. Over 2800 charts were digitized to produce this data base. Charts were prepared by NOAA/National Weather Service Forecast Office in Ann Arbor, U.S. Coast Guard Ninth District Ice Navigation Center in Cleveland, and by the Canadian Atmospheric Environment Service. Chart data sources include NOAA satellite, U.S. Coast Guard side-looking airborne radar (SLAR) and aerial visual reconnaissance, Canadian Coast Guard SLAR and aerial visual reconnaissance, and Atmospheric Environment Service analyses. The data were given to NSIDC by the NOAA Great Lakes Environmental Research Laboratory (GLERL), Ann Arbor, MI.

Geographic Coverage

  • Snow/Ice > Ice Extent
  • Snow/Ice > Lake Ice
Spatial Coverage:
  • N: 49, S: 41, E: -76, W: -93

Spatial Resolution:
  • 5 km x 5 km
Temporal Coverage:
  • 1 November 1960 to 1 May 1979
Temporal Resolution: Not specified
Data Format(s):
  • ASCII Text
Platform(s) AIRCRAFT
Sensor(s): CAMERAS
Version: V1
Data Contributor(s): Raymond Assel
Data Citation

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.

Assel, R. A. 1983. GLERL Great Lakes Ice Concentration Data Base, 1960-1979, Version 1. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: [Date Accessed].
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