Scientists on Wednesday unveiled evidence to suggest global warming is affecting all of Antarctica, home to the world's mightiest store of ice.

The average temperature across the White Continent has been rising for the last half century and the finger of blame points at the greenhouse effect, they said.

The research, published in the British journal Nature, takes a fresh look at one of the great unknowns -- and dreads -- in climate science.Any significant thaw of Antarctica could drown many coastal cities and delta regions. Bigger than Australia, Antarctica holds enough ice to raise global sea levels by 57 metres (185 feet).

Previous monitoring has already pinpointed the Antarctic Peninsula -- the tongue that juts 800 kilometres (500 miles) towards South America -- as a "hotspot" where hundreds of glaciers have been in retreat since the start of the decade.

But until now the news has been reassuring regarding Antarctica's two massive icesheets.Indeed, a common belief is that the icy slabs have even cooled slightly and possibly thickened, partly in response to the chilling seasonal effects of the ozone hole over the South Pole.