Notice

This multimedia story format uses video and audio footage. Please make sure your speakers are turned on.

Use the mouse wheel or the arrow keys on your keyboard to navigate between pages.

Swipe to navigate between pages.

Let's go

Meltwater on an East Antarctic ice shelf

Logo http://rbis.pageflow.io/benemelt/

Understanding Antarctica’s (future) climate is important to all of us, because if Antarctica would melt completely, sea level would be about 58 meters higher than today.

Goto first page

Ice shelves, which are the floating parts surrounding Antarctica, play an important role in the ice sheet's contribution to sea level rise. Ice shelves act as Antarctica’s border control: by providing resistance to the ice, they prevent the land ice to enter the ocean and as such slow down sea level rise.

Goto first page

These ice shelves can melt at the top due to atmospheric warming or at the bottom due to warm ocean water. When this happens, they become potentially unstable and can collapse. Such a collapse has occurred several times over the past decades in West Antarctica.

Goto first page
Close
Before/after view

Larsen-B ice shelf collapse

One such iconic collapse was the disintegration of the Larsen-B ice shelf in West Antarctica in 2002
[To slide before/after: push on play button at bottom left of the page]

Satellite imagery of Larsen B ice shelf in January (left) and March (Right) 2002

Goto first page

In this project, we wondered if these processes could also occur in East Antarctica, where the climate is colder and where the ice shelves are believed to be stable.

Goto first page
Video

Play video

To find out, we went to the Roi Baudouin ice shelf.

Goto first page

We find the presence of a micro-climate in a ~20 km wide band in a region where the ice shelf connects to the land ice. Temperatures are 3ºC higher than anywhere else in the region.

Goto first page
Video

Play video

This warm micro-climate results in extensive melt. 

Goto first page
Video

Play video

The water is not only stored in lakes.

Goto first page

By combining our field measurements with climate models and satellite data we can explain why this micro-climate occurs. It’s the result of strong downslope (katabatic) winds that originate in the ice sheet’s interior. These winds mix the warmer air in the upper atmosphere with the cold air at the surface, creating these warm conditions and enhancing melt in summer.

Goto first page

These same winds blow away the snow, exposing darker ice at the surface, which further amplifies melt.

Goto first page

This meltwater subsequently collects in the subsurface lakes or streams.

Goto first page

The implications of our study are twofold. Firstly, these features are exceptional for East Antarctica, as they are usually only found in Greenland or West Antarctica. This suggests that surface meltwater processes are important on East Antarctica as well, which is usually considered too cold for these processes to occur.

Goto first page

Secondly, although East Antarctic ice shelves do not show signs of instability right now and climate is still relatively stable, we have pinpointed a potential ‘weak spot’ of these ice shelves. In the future, warmer climates undoubtedly intensify melt, increasing the risk of East Antarctic ice shelves becoming unstable, collapsing, and invoking ice loss from East Antarctica

Goto first page
Goto first page

This research is the result of an enormous team effort of an international team consisting of Jan Lenaerts, Stef Lhermitte, Reinhard Drews, Stefan Ligtenberg, Sophie Berger, Veit Helm, Paul Smeets, Michiel van den Broeke, Willem Jan van de Berg, Erik van Meijgaard, Mark Eijkelboom, Olaf Eisen and Frank Pattyn.

Field data were collected in the framework of the BENEMELT project, in collaboration with the BELSPO project ICECON.
BENEMELT benefits from the InBev-Baillet Latour Antarctica Fellowship, a joint initiative of the InBev-Baillet Latour Fund and the International Polar Foundation (IPF) that aims to promote scientific excellence.

We gratefully acknowledge field support from IPF, BELSPO, AntarctiQ, the Belgian Polar Secretariat and the Belgian military.

Goto first page
Scroll down to continue
Swipe to continue