NOAA/NMC/CAC Arctic and Antarctic Monthly Sea Ice Extent, 1973-1990, Version 1 (G00917)
This is the most recent version of these data.
Sea ice extent from January 1973 through August 1990 was digitized from weekly operational sea ice charts produced by the Navy/NOAA Joint Ice Center. Charts were digitized by hand using a 1 degree latitude x 2.5 degrees longitude grid. The grid boxes were then summed in 1 degree latitude x 10 degrees longitude slices, and the ice covered area computed. The data represent the extent of sea ice at the end of each month, given for 36 10-degree longitudinal sectors in each hemisphere. Data were provided by the NOAA National Weather Service National Meteorological Center (NMC) Climate Analyses Center (CAC).
ICE EXTENT SEA ICE CONCENTRATION
AIRCRAFT, GROUND STATIONS, GROUND-BASED OBSERVATIONS, SHIPS
31 January 1973 to 31 August 1990