Sea-ice maps off Antarctica for the BWZ program

Mati Kahru,


        AMSR-E (Advanced Microwave Scanning Radiometer) data is available from multiple sources. Sea ice concentrations are determined from AMSR-E data using the ARTIST Sea Ice algorithm (see and the 89 GHz bands. ARTIST ice maps are available in near-real time (daily updates) from the University of Bremen at With some delay, higher quality data are available using ftp from

        Hemispheric ice concentration maps (both Southern and Northern) are available at 6250 m resolution while regional ice maps are available at 3125 m resolution.

        The Southern Ocean regional datasets at 3125 m resolution include: AntarcticPeninsula, McMurdo, Neumayer, Polarstern, RossSea, ScotiaSea, WeddellSea. The BWZ area is near the border of the two regions: AntarcticPeninsula and ScotiaSea and therefore both datasets had to be merged.

The following analysis used software from Wimsoft ( More details are provided below.



Palmer Meteo Data for 2004


Palmer Meteo Data for 2005


Palmer Meteo Data for 2006


The following operations were used to create the ice maps:

1. HDF files at 3125 m resolution of the AntarcticPeninsula and ScotiaSea regions were downloaded with the wget utility.

2. HDF datasets of the both regions were remapped to a common linear projection map and converted to byte with a command

wam_remap_lla list.txt E:\Projections\BWZ\bwz_linear_320x300_2nm_land.hdf

3. The remapped datasets were merged (composited) together with a command

wam_composite_2sensors E:\sat\ice\AMSR-E_Bremen\AntarcticPeninsula\bwz_2006\*.hdf E:\sat\ice\AMSR-E_Bremen\ScotiaSea\bwz_2006\*.hdf

4.  A a standard grid and land mask was overlaid and the HDF files were converted to PNG with wam_series.

5. Finally, animated GIFs were created for various time periods (July-August for 2004 and 2005) with Babarosa GIF Animator. The animated GIFs are shown above.