Aug. 3 - A hidden, mile-deep rift valley discovered beneath West Antarctica has given scientists new insights into ice loss from the frozen continent, which some experts say contributes almost 10 percent of the rise in global sea levels. Jim Drury reports.
Melting ice in Western Antarctica is causing almost ten per cent of the rise in global sea levels, according to scientists. The discovery of a mile-deep rift valley hidden beneath the ice there could offer an explanation...and help glaciologists make future global warming predictions. British Antarctic Survey geologist Fausto Ferraccioli and Aberdeen University glaciologist Robert Bingham have just published the results of research conducted during a three month trip in 2010. Their work focused on the Ferrigno glacier...and what they found could have serious implications. Marked with a black square is the Ferrigno ice steam. The green trough below is the rift valley discovered by the scientists. Fausto Ferraccioli says the discovery indicates the ice sheet may be more vulnerable than previously thought. SOUNDBITE (English) DR FAUSTO FERRACCIOLI, BRITISH ANTARCTIC SURVEY GEOPHYSICIST, SAYING: "Above these rift valleys lie some of the major glaciers in Antarctica and in this case it's the Ferrigno glacier that lies over this rift, and why is this glacier particularly interesting? Well, this is an area of the ice sheet that is thinning remarkably today and contributing to global sea level rise. So we wanted to understand the geological controls on the processes that are happening today in Antarctica." With further melting, the ice sheet could become prone to warm ocean water flooding beneath, exacerbating the situation. The team say if the ice was stripped away, the rift valley would look spectacular. But it's the implications for rising sea levels that most interests scientists. SOUNDBITE (English) DR FAUSTO FERRACCIOLI, BRITISH ANTARCTIC SURVEY GEOPHYSICIST, SAYING: "Discovering this rift under the ice sheet has important implications for understanding how the geology may influence the future behaviour of the ice sheet..... we need more robust data sets in order to have better models of ice sheet behaviour, so I don't think it's worrying. In fact it's the opposite, I think we can be happy." The West Antarctic Ice Sheet is losing ice faster than any other part of Antarctica, with some glaciers shrinking by more than one metre per year. The scientists say their discovery will add to global research, helping others to come up with solutions. Jim Drury, Reuters