DGES glaciologists head to Antarctica

STAFF from the Department of Geography and Earth Sciences’ Centre for Glaciology have flown out to Antarctica to study the phenomenon of large lakes forming on the surface of ice shelves. Professor Bryn Hubbard and Dr David Ashmore are working with collaborators from Swansea University on the Larsen C ice shelf.Larsen C is significant for scientists trying to understand the effects of climate change on Antarctica. Two other ice shelves in the area, Larsen A and B, have broken up and disappeared since 1995 and scientists have been trying to understand what leads to this.

Speaking ahead of the expedition, Professor Hubbard said;

“The data we get from this work should contribute to our understanding of how the climate is changing; when these lakes first appeared; and their influence, if any, on the breakup of these ice shelves.”

Professor Bryn Hubbard was a member of the Belissima project that drilled in Antarctica during 2010

Professor Bryn Hubbard was a member of the Belissima project that drilled in Antarctica during 2010

“Despite its accessibility, this region of Antarctica is surprisingly poorly known on the ground. Dark patches on satellite images appear each summer and these are interpreted as large surface melt ponds, but no one has actually studied them on the ground; to date we don’t even have a photograph of the lakes we believe we will see on Larsen C.

Most of the research into the Larsen shelves to date has been done using satellites and extends only as far back as the early 1980’s. Drilling into the ice should provide the Aberystwyth team with data extending back over 150 years, into the mid-19th century.

The Aberystwyth team is interested in a process called firnification, a process where almost all Antarctic ice, which forms over some decades,  is compressed by fresh overlying snowfall

By drilling into the ice shelf, the team hopes to be able to identify the extent of ice shelf alteration by surface lake formation and whether these lakes are a recent phenomenon. This occurs because water in the surface lakes freeze within one winter season, substantially altering the internal density and temperature of ice shelves.

Professor Hubbard and Dr Ashmore will be working on the ice shelf until just a few days before Christmas. During this time they will drill at three locations, 60km apart.  The will install measuring instruments which will be left on site for a year and collected in November 2015, when they return to Larsen C.