Digging into Antartic climate history

Ice core cutting showing Dr Nerilie Abram. Photo credit Jack Treist.
Ice core cutting showing Dr Nerilie Abram. Photo credit Jack Treist.

Research into Antarctic climate history has revealed the unusual nature of the recent rapid warming in the Antarctic Peninsula, according to an academic from The Australian National University.

Nerilie Abram, from the Research School of Earth Sciences in the ANU College of Physical and Mathematical Sciences, was part of an international research team that drilled into the ice on James Ross Island and extracted the first comprehensive temperature record for the Antarctic Peninsula. Details of the temperature findings spanning from present day back 15,000 years have been published in Nature.

"The Antarctic Peninsula is one of the fastest warming places on Earth at the moment, and this new ice core lets us for the first time see how recent warming compares with past temperatures," said Abram.

"In particular, the last century of warming has been unusually rapid with the mean temperature increasing by about one and a half degrees - one of the fastest temperature increases seen in the ice core record."

Robert Mulvaney from the British Antarctic Survey, who led the expedition to drill the 364 metre long ice core, said: "The exceptionally fast warming over the last 100 years came on top of a slower natural climate warming that began around 600 years ago - well before the industrial revolution - so it is possible that we are now seeing the combination of natural and man-made warming in this area."

Abram said that the new research shows a very close link between past temperatures and the stability of ice shelves on the Antarctic Peninsula.

"The centuries of ongoing warming have meant that the marginal ice shelves on the northern Peninsula were poised for the succession of collapses that we have witnessed over the last two decades," she said.

"If this rapid warming that we are now seeing continues, we can expect that ice shelves further south along the Antarctic Peninsula that have been stable for thousands of years will also become vulnerable to collapse.

"This new ice core record of Earth’s past climate puts into perspective how unusual the recent warming of the Antarctic Peninsula has been and why we should be concerned about the impact that continued warming will have on the Antarctic ice sheets."