Antarctic ice sheet melt 'not that unusual', latest ice core shows

The latest ice-core analysis from the Antarctic shows that nothing unusual in terms of melting is occurring.

In research published yesterday, a large team of scientists used a deep ice core from the Western Antarctic Ice Sheet Divide to produce records going back some 2,000 years. Their analysis shown that recent melting in that area is in fact normal.

“If we could look back at this region of Antarctica in the 1940s and 1830s, we would find that the regional climate would look a lot like it does today, and I think we also would find the glaciers retreating much as they are today,” comments Eric Steig, a senior earth-sciences boffin at the University of Washington and the lead author on the new research.

Ice loss in recent times from the Western Antarctic - considered to be one of the main places to worry about, if you worry about sea-level rises - may just "not be all that unusual", according to Steig.

The problem, as with many climate change issues, is that conditions in the Western Antarctic vary so much over short time scales that it's hard to work out if any long-term change is actually happening.

“The magnitude of unforced natural variability is very big in this area,” Steig comments.

Another major ice study recently came to similar conclusions regarding the likewise much-discussed Antarctic Peninsula: that recent melting there is not unprecedented, and indeed that various large bits of ice in that area - which today are still intact - probably broke off or melted at times in the pre-industrial past.

Stieg and his colleagues' paper is published in Nature Geoscience. ®

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