Press cutting: Arctic ocean may lose all its ice by 2040

A team of British scientists raise concerns over four of the largest glaciers in the Antarctic, warning they may pose a disproportionate threat to global sea level rises as they slide into the ocean.

Thinning of the Antarctic ice sheets is countered, and in some places, compensated for, by heavier snowfall that acts to rebuild the ice packs to around 2km thick. …

Professor Duncan Wingham [UCL Earth Sciences] and Andrew Shepherd at Edinburgh University reviewed five years of glacier observations in the Antarctic and identified the four glaciers as retreating in unison, driving the thinning of the ice sheets and representing the greatest risk to sea levels. …

As the glaciers flow into the surrounding ocean, they begin to melt, together accounting for around 12% of global sea level rises, or 0.35mm per year.

"Although the amounts of water aren't yet that large, the concern is that we simply don't know what's causing this acceleration of these glaciers. It may be that warm ocean water is getting underneath them and making them flow more easily," said Professor Wingham.

"There are relatively few but very large glacial systems that are driving sea level rise and we should be concentrating our efforts on understanding them. We don't know if they're going to slow down or speed up, but there's a lot of ice backed up in them, so there's reason for concern." …

Ian Sample, 'The Guardian'