Antarctic Peninsula - ASAR - 18 March 2002

ESA’s Envisat spacecraft acquired this image using its Advanced Synthetic Aperture Radar (ASAR) operating in the wide swath mode. It displays an area 400 km by 1000 km, covering almost the entire Antarctic Peninsula.

This region has experienced exceptional atmospheric warming and is a key area for global environmental research. The warming has triggered the retreat and break-up of several ice shelves, culminating in the collapse of the two northern parts of the Larsen Ice Shelf in January 1995 (Larsen A) and in March 2002 (Larsen B).

The ASAR sensor captured the dramatic break-up of Larsen B. Clearly visible in the image is the completely disintegrated ice shelf, which has fractured into thousands of small icebergs and chunks in the Weddell Sea.

This kind of ice shelf break-up is different from the periodic calving processes that produce large icebergs, such as those visible to the east of Larsen B. These icebergs originated 1000 km further south, at the Ronne Ice Shelf, in 2000.

Presently, the large ice shelf section, Larsen-C immediately to the south, appears to have been little affected by climate change. However, if warming continues, this ice mass can be expected to recede as well.

Technical Information:
Instrument: Advanced Synthetic Aperture Radar (ASAR)
Mode: Wide Swath
Acquisition date: 18 March 2002
Orbit number: 00250
Orbit direction: Descending
Polarisation: VV
Resolution: 150 metres
Instrument features: ASAR will play a key role in observing ice shelves, important indicators of polar climate changes. The sensor will make regular observations and enable detailed studies of extent, surface motion and surface melt for Larsen C and all other ice shelves around Antarctica. These measurements, possible even during adverse weather and darkness, are essential in understanding ice dynamics and ice/climate interactions.