2026-06-16T18:39:23Zhttp://nsidc.org/api/dataset/metadata/oai

oai:nsidc.org/G02135.0042026-04-06T18:15:58Zv0_otherv0_allnoaa

G02135.004Sea Ice IndexFetterer, F., Knowles, K., Meier, W. N., Savoie, M., Windnagel, A. K. & Stafford, T.Sea Ice Index2025-07-31Boulder, Colorado USANSIDC: National Snow and Ice Data Center4false10.7265/a98x-0f50https://doi.org/10.7265/a98x-0f50G02135Technical ContactNSIDCUser Servicesnsidc@nsidc.org1-303-492-61991-303-492-2468

CIRES, 449 UCB

University of Colorado

BoulderCO80309-0449USAEARTH SCIENCECRYOSPHERESEA ICEICE EXTENT EARTH SCIENCECRYOSPHERESEA ICEICE GROWTH/MELT EARTH SCIENCECRYOSPHERESEA ICESEA ICE CONCENTRATION Climatology/Meteorology/AtmosphereOceansNOAAPolar Stereo Sea Ice-project Sea IceSea Ice AnomaliesSea Ice ConcentrationSea Ice ConditionsSea Ice ExtentSea Ice PM Polar Stereo-projectSea Ice PM Trends-projectSea Ice Prediction Network-projectSea Ice TrendsSIPN-projectSIPN sea ice-projectSMMR and SSM/I-SSMIS-related productAMSR2Advanced Microwave Scanning Radiometer 2SMMRScanning Multichannel Microwave RadiometerSSM/ISpecial Sensor Microwave/ImagerSSMISSpecial Sensor Microwave Imager/SounderDMSPDefense Meteorological Satellite ProgramDMSP 5D-3/F17Defense Meteorological Satellite Program-F17GCOM-W1Global Change Observation Mission 1st-WaterNimbus-7Nimbus-71978-10-26active-90-39.23-18018030.9890-180180CONTINENTANTARCTICAGEOGRAPHIC REGIONARCTIC25 km25 km1 dayThese data are freely, openly, and fully accessible without restrictions.These data are freely, openly, and fully available to use without restrictions, provided that you cite the data according to the recommended citation at https://nsidc.org/about/use_copyright.html. Near-real-time data provide an estimate of conditions based on information and algorithms available at the time the data are collected (typically within 24 hours). They are processed as data become available, and are not reviewed prior to release.EnglishNOAANOAANational Oceanic and Atmospheric Administrationhttp://nsidc.org/noaa/Data Center ContactNOAAUser Servicesnsidc@nsidc.org1-303-492-61991-303-492-2468

National Snow and Ice Data Center

CIRES, 449 UCB

University of Colorado

BoulderCO80309-0449USAHTTPS0.046 - 1.6 MBPNGHTTPS136 - 651 KBGeoTIFFHTTPS2 - 34 KBCSVHTTPS9 - 90 KBShapefileAgnew, T. A., and S. Howell. 2002a. The use of operational i ce charts for evaluating passive microwave ice concentration data. Internal Report of the Meteorological Service of Canada. 34 pp. Agnew, T. A., and S. Howell. 2002b. Comparison of digitized Canadian ice charts and passive microwave sea-ice concentrations. Procedures of the International Geoscience and Remote Sensing Symposium, July 24-28. Toronto: Canada. Cavalieri, D.J., P. Gloersen and W. J. Campbell. 1984. Determination of sea ice parameters with the NIMBUS-7 SMMR. Journal of Geophysical Research 89 (D4): 5355-5369. Cavalieri, D.J., K.M. St. Germain and C.T. Swift. 1995. Reduction of weather effects in the calculation of sea ice concentration with the DMSP SSM/I. Journal of Glaciology 41: 455-464. Cavalieri, D., P. Gloerson, and J. Zwally. 1990. DMSP SSM/I daily polar gridded sea ice concentrations. Edited by J. Maslanik and J. Stroeve. Boulder, CO: National Snow and Ice Data Center. Digital media. Cavalieri, D., C. Parkinson, P. Gloerson, and H.J. Zwally. 1997, updated 2005. Sea ice concentrations from Nimbus-7 SMMR and DMSP SSM/I passive microwave data, June to September 2001. Boulder, CO: National Snow and Ice Data Center. Digital media and CD-ROM. Cavalieri, D., P. Gloerson, and J. Zwally. 2002, updated daily. Near Real-Time DMSP SSM/I Daily Polar Gridded Sea Ice Concentrations. Edited by J. Maslanik and J. Stroeve. Boulder, CO: National Snow and Ice Data Center. Digital media. Comiso, J. C., and R. Kwok. 1996. Surface and radiative characteristics of the summer arctic sea ice cover from multi-sensor satellite observations. Journal of Geophysical Research 101 (C12): 28, 397-28, 416. Comiso, J. C., and K. Steffen. 2001. Studies of Antarctic sea ice concentrations from satellite data and their applications. Journal of Geophysical Research 106 (C12): 31, 361-31, 386. Emery, W. J., C. Fowler, and J. Maslanik. 1994. Arctic sea ice concentration from Special Sensor Microwave Imager and Advanced Very High Resolution Radiometer satellite data. Journal of Geophysical Research 99: 18,329-18,342. Eppler, D.T., L.D. Farmer, A.W. Lohanick, M.A. Anderson, D. Cavalieri, J. Comiso, P. Gloersen, C. Garrity, T.C. Grenfell, M. Hallikainen, J.A. Maslanik, C. Mätzler, R.A. Melloh, I. Rubinstein, and C.T. Swift. 1992. Passive microwave signatures of sea ice. In Microwave remote sensing of sea ice. Edited by F.D. Carsey. Washington, D.C.: American Geophysical Union. 47-71. Fetterer, F., and N. Untersteiner. 1998. Observations of melt ponds on arctic sea ice. Journal of Geophysical Research 103 (C11): 24,821-24,835. Hollinger, J.P., J.L. Peirce, and G.A. Poe. 1990. SSM/I Instrument Evaluation. IEEE Transactions on Geoscience and Remote Sensing 28 (5): 781-790. Kwok, R. 2002. Sea ice concentration estimates from satellite passive microwave radiometry and openings from SAR ice motion. Geophysical Research Letters 29 (9): 10.1029/202GL014787. Markus, T., and S. T. Dokken. 2002. Evaluation of late summer passive microwave arctic sea ice retrievals. IEEE Transactions on Geoscience and Remote Sensing 40 (2): 348-356. Meier, W. N., M .L. V. Woert, and C. Bertoia. 2001. Evaluation of operational SSM/I algorithms. Annals of Glaciology 33: 102-108. Meier, W. N. 2005. Comparison of passive microwave retrievals with AVHRR imagery in arctic peripheral seas. IEEE Transactions on Geoscience and Remote Sensing 43 (6): 1324-1337. Parkinson, C.L., D.J. Cavalieri, P. Gloersen, H.J. Zwally, and J.C. Comiso. 1999. Arctic sea ice extents, areas, and trends, 1978-1996. Journal of Geophysical Research 104 (C9): 20,837-20,856. Partington, K., T. Flynn, D. Lamb, C. Bertoia, and K. Dedrick. 2003. Late twentieth century Northern Hemisphere sea-ice record from U.S. National Ice Center ice charts. J. Geophys. Res. 108(C11): 3343. doi:10.1029/2002JC001623. Steffen, K., and A. Schweiger. 1991. NASA team algorithm for sea ice concentration retrieval from Defense Meteorological Satellite Program Special Sensor Microwave Imager: comparison with Landsat satellite imagery. Journal of Geophysical Research 96 (C12): 21,971-21,987. Steffen, K., J. Key, D. Cavalieri, J. Comiso, P. Gloersen, K.S. Germain, and I. Rubinstein. 1992. The estimation of geophysical parameters using passive microwave algorithms in microwave remote sensing of sea ice. Edited by F.D. Carsey. Washington, D.C.: American Geophysical Union. 201-231.

Notice: Due to funding limitations, this data set was recently changed to a “Basic” Level of Service. Learn more about what this means for users and how you can share your story here: <a href="https://nsidc.org/data/user-resources/data-announcements/user-notice-level-service-update-data-products">Level of Service Update for Data Products</a>. <br><br> The <a href="/data/seaice_index/">Sea Ice Index</a> provides a quick look at Arctic- and Antarctic-wide changes in sea ice. It is a source for consistent, up-to-date sea ice extent and concentration images, in PNG format, and data values, in GeoTIFF and ASCII text files, from November 1978 to the present. Sea Ice Index images also depict trends and anomalies in ice cover calculated using a 30-year reference period of 1981 through 2010. The images and data are produced in a consistent way that makes the Index time-series appropriate for use when looking at long-term trends in sea ice cover. Both monthly and daily products are available. However, monthly products are better to use for long-term trend analysis because errors in the daily product tend to be averaged out in the monthly product and because day-to-day variations are often the result of short-term weather.

VIEW RELATED INFORMATIONhttps://doi.org/10.7265/a98x-0f50DocumentationGET DATAhttps://noaadata.apps.nsidc.org/NOAA/G02135/HTTPSPROJECT HOME PAGEhttps://nsidc.org/data/seaice_index/Product WebsitePROJECT HOME PAGEhttps://nsidc.org/data/seaice_index/Sea Ice Data at NSIDCCEOS IDN DIFVERSION 9.92025-07-312026-04-06NSIDCVersion SummaryInitial release of Version 4. The data set now uses AMSR2 data as input.NSIDCMinor VersionNSIDCUpdate Frequencyupdated dailyNSIDCCurrent Version1NSIDCSpatial Reference SystemsEPSG:3411NSIDC Sea Ice Polar Stereographic NorthEPSG:3412NSIDC Sea Ice Polar Stereographic SouthNSIDCLevel of ServiceBasicNSIDCFull Dataset CitationFetterer, F., Knowles, K., Meier, W. N., Savoie, M., Windnagel, A. K. & Stafford, T. (2025). <i>Sea Ice Index</i>. (G02135, Version 4). [Data Set]. Boulder, Colorado USA. National Snow and Ice Data Center. <a href="https://doi.org/10.7265/a98x-0f50">https://doi.org/10.7265/a98x-0f50</a>. [<i><describe subset used if applicable></i>].NSIDCRetiredfalseNSIDCRelated Servicesapplication/vnd.nasa.cmr.umm+jsonfalsejroebuckmmt_service_32962S2721063021-NSIDCV0NSIDCV01service2023-06-27T14:22:11.750Zhttps://noaadata.apps.nsidc.org/NSIDCV0_NOAA_Data_HTTPS_File_SystemNOT PROVIDED1NOAA@NSIDC HTTPS File SystemAccess and download NOAA@NSIDC data using a web browser, or through a command line utility such as WGET, or using programming languages such as R or Python.https://nsidc.org/data/user-resources/help-center/how-access-and-download-noaansidc-dataVIEW RELATED INFORMATIONNOAA@NSIDC HTTPS Access GuidePublicationURLUSER SERVICESNSIDC User ServicesEmailnsidc@nsidc.orgDATA ACCESS/RETRIEVALDATA MANAGEMENT/DATA HANDLINGEARTH SCIENCE SERVICESThis is the most current release of this service.AUTHORDEVELOPERPUBLISHERSERVICE PROVIDERNational Oceanic and Atmospheric Administration at the National Snow and Ice Data CenterNSIDC_NOAAhttps://cdn.earthdata.nasa.gov/umm/service/v1.4UMM-S1.4https://noaadata.apps.nsidc.org/NOAA/G02135/NSIDCRelated Toolsapplication/vnd.nasa.cmr.umm+jsonfalsebookerlmmt_tool_12803TL1977942809-NSIDCV0NSIDCV04tool2022-07-29T19:22:17.757ZGOTO WEB TOOLhttps://nsidc.org/data/seaice_index/compare-animate DistributionURLNSIDCV0_Sea_Ice_Index_AnimationWeb User Interface1Sea Ice Index Animation ToolView animated maps of monthly sea ice extent, concentration, anomalies and trends for the Northern and Southern Hemisphere.DATA VISUALIZATIONDATA ANALYSIS AND VISUALIZATIONEARTH SCIENCE SERVICESSERVICE PROVIDERNSIDC User ServicesEmailnsidc@nsidc.orgAUTHORDEVELOPERPUBLISHERSERVICE PROVIDERNational Oceanic and Atmospheric Administration at the National Snow and Ice Data Centerhttp://nsidc.org/noaa/NSIDC_NOAA2021-02-02T00:00:00.000ZFirefoxSafariEdgeChromeThis is the most current release of the tool. https://cdn.earthdata.nasa.gov/umm/tool/v1.0UMM-T1.0https://nsidc.org/data/seaice_index/compare-animate application/vnd.nasa.cmr.umm+jsonfalseamy.steikermmt_tool_14608TL2041935539-NSIDCV0NSIDCV04tool2022-06-13T21:26:07.814ZGOTO WEB TOOLhttps://nsidc.org/data/bist/DistributionURLNSIDCV0_BISTWeb User Interface1.3.1Browse Image Subset Tool Display browse images for five different parameters from three different NOAA@NSIDC Arctic sea ice products in a spreadsheet-like format.DATA VISUALIZATIONDATA ANALYSIS AND VISUALIZATIONEARTH SCIENCE SERVICESSERVICE PROVIDERNSIDC User Services Emailnsidc@nsidc.orgAUTHORDEVELOPERPUBLISHERSERVICE PROVIDERNational Oceanic and Atmospheric Administration at the National Snow and Ice Data Centerhttp://nsidc.org/noaa/NSIDC_NOAADEVELOPERCollinsJulia2017-10-19T00:00:00.000ZFirefoxChromeSafariEdgeThis is the most current release of the tool. https://cdn.earthdata.nasa.gov/umm/tool/v1.0UMM-T1.0https://nsidc.org/data/bist/application/vnd.nasa.cmr.umm+jsonfalsejroebuckmmt_tool_14610TL2041954863-NSIDCV0NSIDCV02tool2022-03-10T17:02:20.847ZGOTO WEB TOOLhttps://nsidc.org/data/seaice_indexDistributionURLNSIDCV0_SeaIceIndexWeb User Interface1Sea Ice Index Daily and Monthly Image ViewerBrowse Arctic- and Antarctic-wide changes in sea ice. View daily and monthly averages of extent and concentration. View time series graphs of Arctic and Antarctic sea ice.DATA VISUALIZATIONDATA ANALYSIS AND VISUALIZATIONEARTH SCIENCE SERVICESSERVICE PROVIDERNSIDC User ServicesEmailnsidc@nsidc.orgAUTHORDEVELOPERPUBLISHERSERVICE PROVIDERNational Oceanic and Atmospheric Administration at the National Snow and Ice Data Centerhttp://nsidc.org/noaa/NSIDC_NOAAAUTHORDEVELOPERWindnagelAnn2021-03-05T00:00:00.000ZChromeFirefoxSafariEdgeThis is the most current release of the tool. https://cdn.earthdata.nasa.gov/umm/tool/v1.0UMM-T1.0PNGhttps://nsidc.org/data/seaice_index/application/vnd.nasa.cmr.umm+jsonfalsebookerlmmt_tool_14487TL2042019418-NSIDCV0NSIDCV03tool2025-01-30T16:51:35.499ZGOTO WEB TOOLhttps://nsidc.org/sea-ice-today/sea-ice-tools/charctic-interactive-sea-ice-graphDistributionURLNSIDCV0_CharcticWeb User Interface3.3Charctic Interactive Sea Ice GraphSee how Arctic/Antarctic sea ice extent changes throughout the calendar year using a customizable graph in a web browser. Compare extents for all years since 1979, and click on any point in any year's trajectory for a map of daily sea ice concentration.DATA VISUALIZATIONDATA ANALYSIS AND VISUALIZATIONEARTH SCIENCE SERVICESSERVICE PROVIDERNSIDC User ServicesEmailnsidc@nsidc.orgDEVELOPERPUBLISHERSERVICE PROVIDERNational Snow and Ice Data Centerhttp://nsidc.orgNSIDC2020-01-15T00:00:00.000Zsea ice extentsea ice concentrationChromeUpdated the latest decadal mean to 2019. https://cdn.earthdata.nasa.gov/umm/tool/v1.0UMM-T1.0https://nsidc.org/sea-ice-today/sea-ice-tools/charctic-interactive-sea-ice-graph