BUENOS AIRES: A top Argentinean expert on the Antarctic has warned that rapidly melting glaciers cascading into the ocean could raise sea level by 7 metres.

Hernan de Angelis of the Argentine Antarctic Institute said on Thursday that it could take 50 to 200 years for such a catastrophic development to take place.

De Angelis said an increase in the region’s average temperature of 2.5 degrees Celsius over the past 50 years has led to the predictions. A rapidly rising sea level would have disastrous effects on the world’s thickly settled coastal areas.

Along with his colleague Pedro Skvarca, de Angelis has been investigating the issue intensively since the breaking up of the Larsen ice shelf — a 700-kilometre-long floating ice barrier — during the uncommonly mild summer of 1994-1995.

The scientists found the first evidence that the glacier had melted in “slow motion”, pouring lava-like into the ocean.

Using satellite images and airborne photographs, the scientists examined another glacier, the Sjogren Glacier, and found it was slipping towards the ocean at rate of 2.4 metres per day in 2001. Just two years before, in 1999, it was moving at only one metre per day, the two scientists wrote in the scientific magazine, “Science”.

The investigations delivered the first hard evidence that there was something to the old concept that pack ice served as “a sort of dike against land ice sliding into the sea”, Skvarca said. That idea had been dismissed as antiquated by most Antarctic researchers, who held that the ice shelves that swam along the coast were unimportant for the life of land-based glaciers.

Looking at photographs taken from low-flying aeroplanes, De Angelis and Skvarca found clear evidence that turbulent forces inside the glacier were acting act to produce warping and faults on the surface. These features were seen as a clear indication that several glaciers had already started to move.—dpa