The Guardian reports:

Antarctica is likely warming at almost twice the rate of the rest of the world and faster than climate change models are predicting, with potentially far-reaching implications for global sea level rise, according to a scientific study.

Scientists analysed 78 Antarctic ice cores to recreate temperatures going back 1,000 years and found the warming across the continent was outside what could be expected from natural swings.

In West Antarctica, a region considered particularly vulnerable to warming with an ice sheet that could push up global sea levels by several metres if it collapsed, the study found warming at twice the rate suggested by climate models.

Climate scientists have long expected that polar regions would warm faster than the rest of the planet – a phenomenon known as polar amplification – and this has been seen in the Arctic.

Dr Mathieu Casado, of the Laboratoire des Science du Climat et de l’Environnement in France and lead author of the study, said they had found “direct evidence” that Antarctica was also now undergoing polar amplification.

“It is extremely concerning to see such significant warming in Antarctica, beyond natural variability,” he said.

Antarctica is the size of the continental US and Mexico combined, but has only 23 permanent weather stations and only three of these are away from the coast.

Casado and colleagues examined 78 Antarctic ice cores that hold a record of temperature and then compared those temperatures to climate models and observations.

The research, published in the journal Nature Climate Change, found Antarctica was warming at a rate of between 0.22C and 0.32C per decade, compared to 0.18C per decade predicted by climate models. [Continue reading…]