MercoPress. South Atlantic News Agency

Warn of disappearing Antarctic glaciers.

Delegates at the climate change conference in Exeter have heard of the contribution that rapid thinning of the Antarctic ice sheet is making to global sea-level rises.

Speaking at the Met Office's 'Avoiding Dangerous Climate Change' conference, Director of the British Antarctic Survey (BAS), Professor Chris Rapley, warned that there was "real cause for concern". He said: "Satellite measurements tell us that a significant part of the West Antarctic ice sheet in this area is thinning fast enough to make a significant contribution to sea level rise, but for the present, our understanding of the reason for this change is little better than hypothesis. The last Intergovernmental Panel on Climate Change (IPCC) report characterised Antarctica as a slumbering giant in terms of climate change. I would say that this is now an awakened giant."

Scientists from BAS, US National Science Foundation and the University of Texas embarked on an airborne geophysical survey of Antarctica, following the discovery of rapid thinning in two major glaciers in the Amundsen Sea of the West Antarctic ice sheet.

The scientists collected data from Pine Island and Thwaites glaciers. The IPCC's predicted future sea level rise in 2001 was based on the assumption that the Antarctic ice sheet would not make a significant contribution over the next one hundred years. However, BAS scientists said that this area IS contributing, but could not confirm whether this would be a short-term development or if it was a result of recent or ancient climate change.

In 2002, 500 billion tonnes of ice from the Larsen B self broke up into thousands of small icebergs. The latest research shows that the glaciers that fed the ice shelf have accelerated and thinned dramatically, as a result of the ice shelf collapse.

Scientists suggested that ice shelves may have an important role in stabilising the ice sheet in Antarctica and warned that the future loss of the largest ice shelves in the Antarctic could eventually cause accelerated and dramatic sea level rise.