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GOMO-Funded Project

Sea Ice Index

  • Principal Investigator(s):
  • Project Institution(s): National Snow and Ice Data Center
  • Fiscal Year: 2024
  • Award Period:
    10/01/2023 - 09/30/2024

Obtaining insights into sea ice changes in Polar Regions

Created in 2002 and updated daily, the Sea Ice Index provides a quick look at polar-wide changes in sea ice. Monthly Sea Ice Index images provide sea ice extent with an outline of the 30-year (1981-2010) median extent for that month, as well as sea ice concentration, anomalies, and trends in concentration. With over 3000 registered users, the Sea Ice Index has achieved broad recognition as a top data product for sea ice trends and analyses since its inception. The data has many publication and policy-related impacts, including being used in the annual sea ice essay in the NOAA Arctic Report Card and aiding NOAA Fisheries in identifying critical habitat boundaries for endangered Arctic seal species. The Sea Ice Index also serves as a critical outreach tool on the impacts of sea ice extent, and is used in high school classrooms and NOAA’s Science on a Sphere. It is also considered the authoritative source on Arctic sea ice extent for major news outlets and the Congressional Research Service.

This map shows sea ice concentration in the Arctic for August 2024. Darker blues indicate lower sea ice concentration. Magenta lines indicate average historical sea ice extent boundaries from 1981-2010. (Credit: National Snow and Ice Data Center)

Project Data

  • Project Datasets

    • Daily and monthly images of sea ice extent and concentration in the Northern Hemisphere Access Data
    • Daily and monthly images of sea ice extent and concentration in the Southern Hemisphere Access Data
    • Daily and monthly sea ice extent in millions of sq km, with no additional analysis (North Hemisphere Daily Data) Access Data
    • Daily and monthly sea ice extent in millions of sq km, with no additional analysis (North Hemisphere Monthly Data) Access Data
    • Daily and monthly sea ice extent in millions of sq km, with no additional analysis (South Hemisphere Daily Data) Access Data
    • Daily and monthly sea ice extent in millions of sq km, with no additional analysis (South Hemisphere Monthly Data) Access Data
    • Daily sea ice extent, with parameters derived from daily extent, for both hemispheres (time series) Access Data

Publications and Reports

  • Fetterer, F., K. Knowles, W. N. Meier, M. Savoie, and A. K. Windnagel. (2017). Sea Ice Index, Version 3 [Data Set]. Boulder, Colorado USA. National Snow and Ice Data Center. https://doi.org/10.7265/N5K072F8. Date Accessed 02-28-2024Access