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Data Set ID:

NOAA/NSIDC Climate Data Record of Passive Microwave Sea Ice Concentration, Version 2

This data set provides a Climate Data Record (CDR) of sea ice concentration from passive microwave data. It provides a consistent, daily and monthly time series of sea ice concentrations from 09 July 1987 through the most recent processing for both the north and south polar regions on a 25 km x 25 km polar stereographic grid.

The NOAA/NSIDC CDR is based on the recommendations from the National Research Council (NRC) (2004). It is produced from gridded brightness temperatures from the Defense Meteorological Satellite Program (DMSP) F8, F11, and F13 Special Sensor Microwave Imager (SSM/I) passive microwave radiometers and the DMSP F17 Special Sensor Microwave Imager/Sounder (SSMIS) passive microwave radiometer.

Variables containing standard deviation, quality flags, and projection information are also included in the netCDF files. Data are available via FTP.

Version Summary:
  • Two new variables added to the netCDF files:
    • melt_onset_day_seaice_conc_cdr
    • melt_onset_day_seaice_conc_monthly_cdr
  • Calculation of melt_start_detected flag in the qa_of_seaice_conc_cdr variable was updated

See the documentation for full details on these variables.

Geographic Coverage

  • Sea Ice > Sea Ice Concentration
Spatial Coverage:
  • N: 89.84, S: 31.1, E: 180, W: -180

  • N: -39.36, S: -89.84, E: 180, W: -180

Spatial Resolution:
  • 25 km x 25 km
Temporal Coverage:
  • 26 October 1978 to 31 December 2015
(updated 2016)
Temporal Resolution: 1 day
Data Format(s):
  • NetCDF
Platform(s) DMSP, DMSP 5D-2/F11, DMSP 5D-2/F13, DMSP 5D-2/F8, NIMBUS-7
Sensor(s): SMMR, SSM/I
Version: V2
Data Contributor(s): Walt Meier, F. Fetterer, Ruth Duerr, Julienne Stroeve, Matthew Savoie, Sean Mallory
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.

Meier, W., F. Fetterer, M. Savoie, S. Mallory, R. Duerr, and J. Stroeve. 2013, updated 2016. NOAA/NSIDC Climate Data Record of Passive Microwave Sea Ice Concentration, Version 2. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: [Date Accessed].

Literature Citation

As a condition of using these data, we request that you acknowledge the author(s) of this data set by referencing the following peer-reviewed publication.

  • Peng, G., W. Meier, D. Scott, and M. Savoie. 2013. A long-term and reproducible passive microwave sea ice concentration data record for climate studies and monitoring, Earth Syst. Sci. Data. 5. 311-318.

No technical references available for this data set.
No FAQs or How Tos available for this data set.

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