Global Sea Ice Concentration climate data record (SMMR/SSMI/SSMIS), release 3

Released Climate product

The sea-ice concentration Climate Data Record covering the northern and southern hemispheres. Extended by the Interim Climate Data Record OSI-430-a.
L3/L4 daily files, and monthly average files, and monthly sea-ice extent/area indicator.

Acronym : GBL SICO CDR R3
Product navigator reference :


OSI SAF producer : Norwegian Meteorological Institute
Identifier : OSI-450-a
Digital object identifier (DOI) 10.15770/EUM_SAF_OSI_0013
Acronym for EDC (APNM) : OR450ASICO
Citation : See at bottom
Processing level : L3+L4
Satellite input : SMMR, SSM/I and SSMIS from CM SAF (FCDR R4)
Other input : NWP outputs (Copernicus C3S ERA5)
Temporal sampling : 24 h (before July 1987: 48 hours)
Central time : 12:00
Spatial coverage : Global
Spatial sampling : 25 km
Projection : EASE2
File Formats : HL FTP Server (NetCDF4), EDC (NetCDF4)
Characteristics & methods : Daily averaged fractional ice cover in percentage.
Includes per-grid cell uncertainties.
Monthly averaged fractional ice cover are also distributed, as well as monthly sea-ice extent/area indicator.
Data Access

OSI SAF FTP server

Directory: ice/conc/v3p0

Redistribution by Copernicus Marine Service

Accuracy Requirements
Target accuracy : 8 %
Verification/validation method : Primary Method: Direct comparison against high-quality 0% and 100% SIC reference data (stemming from the ESA CCI projects, Pedersen et al. 2019). See additional methods in the comments at the bottom of this page.
Applications and users
Usage : Climate models, NWP and Ocean/Ice reanalyses, environmental agencies.
Authorised to be operational / released :
Declared operational / released since :
On FTP server since :
First date :
Last date :
Full series temporal coverage : 1978-2020
Detailed history :

This Climate Data Record has been reprocessed several times:

[1st release] OSI-409 and OSI-409-a

[2nd release] OSI-450 was released in 2017

[3rd release] OSI-450-a was released in 2022. We advice you to use the latest release.

Citation : OSI SAF Global sea ice concentration climate data record 1978-2020 (v3.0, 2022), OSI-450-a, doi:10.15770/EUM_SAF_OSI_0013. EUMETSAT Ocean and Sea Ice Satellite Application Facility. Data extracted from [distributor/distribution mean]: ([extracted period],) ([extracted domains],) accessed [download date]

The content within square brackets "[…]" is to be replaced with whatever distributor, period, domain or download date is relevant to the data being used. The "extracted period" and "extracted domains" are only needed if a subset of the data is being used.
Suggestions for "distributor/distribution mean": OSI SAF FTP server/the EUMETSAT Data Centre/EUMETCast/name and URL of a redistributor...
  • Verification/validation methods:

    • Primary Method: Direct comparison against high-quality 0% and 100% SIC reference data (stemming from the ESA CCI projects, Pedersen et al. 2019).
    • Additional: Comparison of SIC to US National Ice Center charts, to document the temporal consistency since 1979 (but limited by the low consistency of ice charts).
    • Additional: Comparison of Monthly Sea Ice Extent and Area time series with those of the US NSIDC Sea Ice Index (absolute level, departure from climatology, trend).
    • Additional : An evaluation of the uncertainties will be performed (at 0 % and 100 %, similar to in Lavergne et al., 2019). The traceability to SI units will be investigated.


  • Daily averaged fractional ice cover in percentage, processed from passive microwave satellite data (SMMR, SSM/I, and SSMIS) over the polar regions. Sea ice concentration and its uncertainties are calculated from swath observations, and averaged and gridded to the daily fields. This CDR benefited from R&D activities in the ESA CCI projects.

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