MercoPress. South Atlantic News Agency

Antarctic glaciers in mass retreat.

Glaciers in the Antarctic are retreating at an increasing rate, in what scientists said on Thursday was a clear sign of climate change.

Thursday was a clear sign of climate change. Most of the glaciers on the Antarctic Peninsula, near the southernmost tip of South America, have retreated over the past 50 years as temperatures have warmed, according to a study from the British Antarctic Survey and US Geological Survey. Inland glaciers appear to be accelerating their descent to the ocean, threatening to raise the sea level.

David Vaughan, one of the authors of the study, said: "The widespread retreat of the glaciers on the Antarctic peninsula over the past 50 years was largely caused by climate change. Are humans responsible? We can't say for sure but we are one step closer to answering this important question."

The survey joins a growing body of research on climate change. A study of the Arctic last year found that the ice cap was half the thickness it was 30 years ago and a tenth smaller.

An American study in February found that warming in the world's oceans could have been caused only by human activity in increasing the concentration of carbon dioxide in the atmosphere. The gas, generated by burning fossil fuels, traps heat on Earth.

Nicola Saltman, a climate change policy adviser for the environmental group WWF, said: "This is another piece of evidence showing that climate change is real and happening and all governments should prioritise emissions reduction."

Of the 244 glaciers surveyed in the Antarctic, 87 per cent had retreated, by an average of 600 metres. The rate of retreat accelerated to 50m per year in the past five years, faster than at any other time in the past half century.

The survey, published on Friday in the peer-review journal Science, is the first comprehensive study of glaciers on the coast of the Antarctic Peninsula. It examined more than 2,000 aerial photographs going back to the 1940s and satellite images from the past 40 years to map the ice's retreat. Temperatures have risen by about 2° Celsius in the past 50 years, a "dramatic" rise, said Alison Cook, a co- author of the report.

Climate change has become a more contentious issue since the entry into force of the Kyoto protocol in February. While most developed nations have ratified the treaty, which requires that they cut the emissions of carbon dioxide, the US and Australia have rejected it. There are also fierce tussles over whether developing nations should be required to cut emissions.

Talks on global warming among European Union and US officials this week produced "a frank exchange of views", said Lord Whitty of the UK.