Polar sea-ice concentration from OSI SAF
- Coverage, spatial and temporal resolution
- Data quality
- Contact person
- Data citation
RESTRICTED:This link to the data set is only available for a restricted user group. The data set is only accessible in CEN/MPI net or accessible from external nets with a customer account. Please contact ICDC if you would like to access this data from outside the network.
- Get OSI-SAF sea ice data via FTP
- Access OSI-SAF sea ice data via OPeNDAP
- Data access via file system: /data/icdc/ice_and_snow/osisaf_iceconc/
This is the fully reprocessed EUMETSAT Ocean and Sea Ice Satellite Application Facility (OSI SAF) team Sea-Ice Concentration (SIC) Climate Data Record (CDR) OSI-450 and its extension, the interim CDR (ICDR) OSI-430-b. Processing chains are identical for OSI-450 and OSI-430-b. Sea-ice concentrations over the polar regions are derived from passive microwave satellite data of SMMR, SSM/I and SSMIS, covering years 1979 to 2020. More recent ICDR data extending this data set to toady minus 16 days is available at the OSI-SAF Website (see references).
The basic principles and methodologies that were the backbone of the previous CDR (OSI-409) are still featured in OSI-450 (e.g. atmospheric correction of brightness temperature with NWP re-analysis data, state of the art algorithms, dynamic tie-points, uncertainties, etc...). They were nevertheless all revisited for this new release, through dedicated R&D in the OSI SAF project and in the ESA Climate Change Initiative Sea Ice projects, whose contribution is acknowledged. Key improvements embedded in OSI-450 are more accurate and stable algorithms, open water filters to limit false ice detection over the ocean, and more realistic uncertainty estimates.
There is more information in the references. The Algorithm Theoretical Basis Document (ATBD), the Product User Manual and the Validation Report give details about the sea-ice concentration retrieval, additional filters, optimization procedures, and the error estimation as well as some aspects about the validation.
Last update of data set at ICDC: September 16, 2021
|Main (filtered) sea-ice concentration||0% ... 100%|
|Raw sea-ice concentration||< 0% ... > 100%|
|Total uncertainty (total standard error)||0% ... 100%|
|Smearing uncertainty (smearing standard error)||0% ... 100%|
|Retrieval uncertainty (algorithm standard error)||0% ... 100%|
|Status flag (bit coded)||0 ... 255|
Period and temporal resolution:
- 1979-01-01 to 1987-08-20
- Every other day
- 1987-08-21 to 2021-08-31 (CDR until 2015-12-31, ICDR afterwards)
- Daily (Monthly data are available on request)
Coverage and spatial resolution:
- Northern and Southern Hemisphere
- Spatial resolution: 25 km x 25 km, EASE2 grid (see http://nsidc.org/data/ease/ )
- Geographic longitude: 0°E to 360°E
- Geographic latitude: about 41°N and 41°S to 90°N and 90°S, respectively, coverage is larger in the grid corners
- Dimensions: 432 columns x 432 rows
- Altitude: 0.0 m
For each grid cell and each available day an error estimate and a status flag is given.
The error estimates describe the uncertainty inherent in the retrieval, i.e. due to the input data used, and from the tie points and the uncertainties caused by gridding sea-ice concentrations which are computed at footprint level into the used EASE2 grid.
The status flag provides information about the surface type and whether values are the originally retrieved ones or whether they are the result of flagging and/or interpolation.
The unfiltered sea-ice concentration data set is for the more advanced users and is described in the Product User Manual. Missing days are given in the Product User Manual as well, see references.
Norwegian Meteorological Institute (met.no)
email: thomas.lavergne (at) met.no
Norwegian Meteorological Institute
email: osisaf-manager (at) met.no
ICDC / CEN / University of Hamburg
email: stefan.kern (at) uni-hamburg.de
- OSI-SAF Website, http://osisaf.met.no/p/ice/ice_conc_cdr_v2.html
- ESA Climate Change Initiative (ESA-CCI), https://climate.esa.int/en/
- ESA CCI Sea Ice Website, http://esa-cci.nersc.no
- OSI SAF High Latitude Processing Center, https://osisaf-hl.met.no/
- Lavergne, T., et al., 2019, Version 2 of the EUMETSAT OSI SAF and ESA CCI Sea Ice Concentration Climate Data Records, The Cryosphere, 13(1), 49-78, https://doi.org/10.5194/tc-2018-127
- Kern, S., et al., 2019, Satellite Passive Microwave Sea-Ice concentration data set inter-comparison: Closed ice and ship-based observations, The Cryosphere, 13(12), 3261-3307, https://doi.org/10.5194/tc-13-3261-2019 .
- Kern, S., et al., 2020, Satellite passive microwave sea-ice concentation data set intercomparison for Arctic summer conditions, The Cryosphere, 14(7), 2469-2493, https://doi.org/10.5194/tc-14-2469-2020 .
- ATBD for the OSI SAF Global Sea Ice Concentration Climate Data Record (pdf, not barrier free)
- Global Sea Ice Concentration Climate Data Record Product User Manual for Product OSI-450 (pdf, not barrier free)
- Sea Ice Concentration Climate Data Record Validation Report OSI-450 (pdf, not barrier free)
Please cite the data as follows:
EUMETSAT Ocean and Sea Ice Satelitte Application Facility. Global sea ice concentration [interim] climate data record 1979-2015 (v2.0, 2017) [2016-2021]. Norwegian and Danish Meteorological Institutes. Available from osisaf.met.no., doi.org/10.15770/EUM_SAF_OSI_0008 [last accessed September 16 2021].
All intellectual property rights of the OSI SAF products belong to EUMETSAT. The use of these products is granted to every interested user, free of charge. If you wish to use these products, EUMETSAT copyright credit must be shown by displaying the words "copyright (year) EUMETSAT" on each of the products used.
and with the following acknowledgments:
Thanks to ICDC, CEN, University of Hamburg for data support.