'Worst In 1,000 Years' Antarctic Ice-Melt Is

Summer ice in parts of Antarctica is melting at a faster rate than at any time in the past 1,000 years, new research shows.
The study by Australian and British researchers indicates that even small increases in temperature could now lead to significant spike in summer ice melt on the peninsula.

The scientists drilled a 364m (1,197ft) deep ice core on James Ross Island, near the northern tip of the Antarctic Peninsula, to measure past temperatures and compare them with summer ice melt levels.

Visible layers in the ice core indicated periods when summer snow on the ice cap thawed and then refroze.

They found that, while the temperatures have gradually increased by 1.6C (2.9F) over 600 years, the rate of ice melting has been most intense over the past 50 years.

In fact, summer ice melt has been 10 times more intense over the past 50 years compared with 600 years ago, the study shows.

"What it means is that the Antarctic peninsula has warmed to a level where even small increases in temperature can now lead to a big increase in summer ice melt," lead researcher Nerilie Abram said.

"This has important implications for ice instability and sea level rise in a warming climate."

Dr Abram said the findings are "definitely evidence that the climate and the environment is changing in this part of Antarctica".

Robert Mulvaney, from the British Antarctic Survey, said the stronger ice melts are likely responsible for faster glacier ice loss and some of the dramatic collapses from the Antarctic ice shelf over the past 50 years.

The research from the Australian National University and the British Antarctic Survey was published in the Nature Geoscience journal.