Institute of Oceanography

University of Hamburg

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Institute of Oceanography
University of Hamburg
Bundesstraße 53
D-20146 Hamburg
Tel.: +49 40 42838-2605 / -5449
Fax: +49 40 42838-7488
E-Mail:  waltraut.domke-sommer(at)

AMSR-E sea ice concentration

prepared by: Gunnar Spreen and Lars Kaleschke

News: End of AMSR-E time series on October 2, 2011

October 2011: The AMSR-E instrument stopped producing data on 04 October 2011: NSIDC News. There will be no updates of the sea ice concentration data after that date. With the end of the AMSRE-E data production this 89 GHz sea ice concentration data set comes to an end. The data set spans the time from 19 June 2002 to 2 October 2011. All data can be found in our data archive.

September 2011: The September 2011 Arctic sea ice minimum extent is the second lowest in the more than 35 year long satellite data time series.

May 2010: The ASI AMSR-E sea ice concentration dataset has been reprocessed for the complete AMSR-E timeseries starting in 2002. The new version (v5.6i) applies updated AMSR-E brightness temperatures from NSIDC, a new Arctic land mask, and corrects an error with the maximum ice extent mask. For more details see the AMSRE-ASI-Info.txt file.

Sea ice concentration maps / time series

  • An archive with AMSR-E ASI sea ice concentration data for the Arctic and Antarctic can be found on our ftp server.

    The archive contains a consistent time series of sea ice concentrations on a 6.25 km grid since the start of operation of AMSR-E on 18 June 2002. News, information and release notes of the dataset can be found in the AMSRE-ASI-Info.txt file.

  • Example of AMSR-E sea ice concentration maps:

First and last AMSR-E Sea Ice Concentration Map



Sea ice concentration maps of the Arctic and Arctic using the first (2002-06-19) and last (2011-10-02) AMSR-E data available. All images and data can be found in our Opens external link in new windowarchive. More and also regional up-to-date sea ice maps can be found on the sea ice web page of the University of Bremen.
  • Arctic and Antarctic total sea ice area and extent (left), area anomalies (middle), and seasonal cycle (right):

Sea ice area (black) and extent (red) for the Arctic and Antarctic for the complete archived ASI AMSR-E time series. The "hole" at the North Pole is assumed to be 100% ice covered. Sea ice area anomalies for the Arctic (red) and Antarcic (blue) for the complete AMSR-E time series. Anomalies are calculated daily with respect to the mean of the accordant days for all years of the time series.Seasonal cycles of sea ice area for all years covered by AMSR-E data starting 2002. The Arctic seasonal cycles are shown in the top figure and the Antarctic ones in the bottom  figure.

Minimum sea ice extent




2008 2009
2009 Minimum Sea Ice Extent
Map of the 2011 Arctic minimum sea ice extent, which occurred on 8 September 2011. For comparison the record minimum sea ice extent of September 2007 and the mean September sea ice extents of the five  years 1979 to 1983 are shown as red and orange contours, respectively. The 2011 minimum sea ice extent is  the second lowest in the more than 35 year long satellite data time series. The 2011 sea ice extent is only about 0.1 million km2 larger than 2007. Map of the 2007 Arctic minimum sea ice extent, which occurred on 17 September 2007 and was the lowest extent in the 35 year long satellite observation history. For comparison the mean September sea ice extents of the five years 2002 to 2006 and the five years 1979 to 1983 are marked as red and orange contours, respectively. 20052006
 2006 Sea Ice Minimum
Maps of the 2010, 2009, 2008, 2006 and 2005 Arctic minimum sea ice extents with contours of mean Sep. 2002-2006 and 1979-1983 ice extent (2005 contours:  2002-2005 and 1979-1982,). The 2009 and 2008 maps additionally show the 2007 sea ice minimum for comparison.



Animation of Arctic, Antarctic, and combined Arctic-Antarctic sea ice concentration using the ARTIST sea ice (ASI) algorithm for AMSR-E radiometer data (Jun 2002 to Sep 2007; mpeg1 format; 55 MB, 55 MB, and 83 MB, respectively). The animation ends in 2007 with the all time minimum sea ice coverage during the 35 years of satellite observations.

Citation Information

If you use data or plots from this website please cite the data accordingly: "University of Hamburg, Institute of Oceanography, Gunnar Spreen and Lars Kaleschke" and/or cite our article "Spreen, G., L. Kaleschke, and G. Heygster (2008), Sea ice remote sensing using AMSR-E 89-GHz channels, J. Geophys. Res., 113, C02S03, doi:10.1029/2005JC003384."

If you need a complete citation for the data you may use: Spreen, G., and L. Kaleschke (2008), "AMSR-E ASI 6.25 km Sea Ice Concentration Data, V5.4", Institute of Oceanography, University of Hamburg, Germany, digital media (
The year and data version should fit the used data, i.e. the year when the data was obtained. The data version can be found at the bottom of the image plots.