Reprocessed ASI data from 2002 to Oct 2018: Version 5.4

We  have just completed reprocessing all ASI ice concentration data based on AMSR-E or AMSR2 data for the  complete period, i.e.,

  • 1 June, 2002 to 4 Oct, 2011 (AMSR-E)
  •  July, 2012 to 27 Oct,2018 (AMSR2).

The reprocessing has been done for the hemispheric maps only. i.e., Arctic/Antarctic (6.25 km grid spacing) and Arctic3125/Antarctic3125 (3.125 km grid spacing).

The tie points of the ASI algorithm were the same (version 5). However, some other details as the version of GMT (generic mapping tools) used for gridding the data and defining land masks and coast lines have changed over the years. The reprocessed data are therefore consistent with respect to  all this, and have the version number 5.4. The full version number is also part of all file names ('v5.4'); the new files are stored alongside the files of previous versions  5.2 and 5.3 which just have 'v5' in their file names.

The new data being processed every day will be switched to version 5.4 in the next weeks which implies the mentioned change in the file names ('v5.4' instead of just 'v5')

All details about the ASI ice concentration data can be found in the the new ASI user guide

Daily AMSR2 Sea ice concentrations



Daily Ice Thickness and RV Polarstern Position

SMOS Thin Sea Ice Thickness

RV Polarstern

thickness of thin sea ice RV Polarstern

2018 Arctic Sea Ice Minimum

The 2018 sea ice minimum extent was reached on 2018-09-21. Sea ice extent is now increasing again.


Time Series

Minimum & Maximum

Diagram: Arctic sea ice extent during previous 7 years
September is the month when in the Arctic the sea ice area reaches its minimum. The map and time series show a comparison of current ice conditions to previous years.