Climate Data

Sea Ice Concentration data reprocessed from SSMR & SSMI, by Eumetsat

The Eumetsat Ocean and Sea Ice Satellite Applications Facility provides a "reprocessed" data set of Arctic and Antarctic sea ice concentration for 1978-2009. Source data are the SMMR and SSM/I passive microwave brightness temperatures. Three algorithms are utilized: the Technical University of Denmark algorithm is applied to the SSM/I data from 1991 onwards; the Bootstrap and the Bristol algorithms are combined for the SMMR and SSM/I data for 1978-1991. The Bootstrap is said to have lower sensitivity to atmospheric noise in areas of open water (helping to delineate the ice edge), while the Bristol algorithm is applied due to its lower sensitivity to ice surface emissivity variability. In general, atmospheric effects are more pronounced for relatively low ice concentrations. More information is available in the documentation and publications linked below.

Key Strengths:

  • Long, daily or every-other-day timeseries of sea ice in the Arctic and Antarctic
  • Uses dynamic tie points adjusted to typical brightness temperatures of ice and open water; this may account for satellite drift and inter-satellite calibration issues
  • Corrections are applied for weather effects (water vapor and surface roughness) on the passive microwave signals

Key Limitations:

  • Not fully updated to present
  • Few publications about it; properties are not widely known
  • The weather corrections depend on the ERA-40 and ECMWF operational forecasts and this could possibly introduce non-climatic biases

Years of Record

1978/10 to 2009/10
temporal metadataID:




Data Time Period Extended?

no, data set not being extended

Spatial Resolution

12.5 x 12.5 km

Ocean or Land

Ocean Only

Missing Data Flag

missing data present

Vertical Levels

Input Data


Earth system components and main variables

Suggested Data Citation

EUMETSAT Ocean and Sea Ice Satelitte Application Facility. Global sea ice concentration reprocessing dataset 1978-2009 (v1.1, 2011), [Online]. Norwegian and Danish Meteorological Institutes. Available from

Data Access: Please Cite data sources, following the data providers' instructions.

Key Figures

Click the thumbnails to view larger sizes



Artic sea ice: Eumetsat reprocessed. Arctic sea ice averaged over 2003-2007 for the month of March according to the Eumetsat Sea Ice Reprocessed data set. Figure by D. Schneider.

Cite this page

National Center for Atmospheric Research Staff (Eds). Last modified 20 Aug 2013. "The Climate Data Guide: Sea Ice Concentration data reprocessed from SSMR & SSMI, by Eumetsat." Retrieved from

Acknowledgement of any material taken from this page is appreciated. On behalf of experts who have contributed data, advice, and/or figures, please cite their work as well.