Data Set ID:

Bootstrap Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I-SSMIS, Version 3

This sea ice concentration data set was derived using measurements from the Scanning Multichannel Microwave Radiometer (SMMR) on the Nimbus-7 satellite and from the Special Sensor Microwave/Imager (SSM/I) sensors on the Defense Meteorological Satellite Program's (DMSP) -F8, -F11, and -F13 satellites. Measurements from the Special Sensor Microwave Imager/Sounder (SSMIS) aboard DMSP-F17 are also included. The data set has been generated using the Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E) Bootstrap Algorithm with daily varying tie-points. Daily (every other day prior to July 1987) and monthly data are available for both the north and south polar regions. Data are gridded on the SSM/I polar stereographic grid (25 x 25 km) and provided in two-byte integer format.

This is the most recent version of these data.

Version Summary:

Changes to this version include:

  • Intercalbration techniques between SMMR and F08, as well as F08 and F11 were changed to match sea ice area rather than sea ice extent.
  • Ocean tie points now change each day (similar to the ice tie points) based on brightness temperatures for that day.
  • The threshold for the lower limit for ice was relaxed to allow retrieval of ice at 10 percent ice concentration.

    COMPREHENSIVE Level of Service

    Data: Data integrity and usability verified; data customization services available for select data

    Documentation: Key metadata and comprehensive user guide available

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

    See All Level of Service Details

    Data Format(s):
    • Binary
    Spatial Coverage:
    N: -39, 
    N: 90, 
    S: -90, 
    S: 30, 
    E: 180, 
    E: 180, 
    W: -180
    W: -180
    Platform(s):DMSP 5D-2/F11, DMSP 5D-2/F13, DMSP 5D-2/F8, DMSP 5D-3/F17, Nimbus-7
    Spatial Resolution:
    • 25 km x 25 km
    Sensor(s):SMMR, SSM/I, SSMIS
    Temporal Coverage:
    • 1 November 1978 to 31 December 2021
    Temporal Resolution1 day, 1 monthMetadata XML:View Metadata Record
    Data Contributor(s):Comiso, J. C.

    Geographic Coverage

    Other Access Options

    Other Access Options


    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.

    Comiso, J. C. 2017. Bootstrap Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I-SSMIS, Version 3. [Indicate subset used]. Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center. doi: [Date Accessed].

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    How To

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