“Irreversible Thaw” Of West Antarctic Ice

By bogotapost May 16, 2014
Credit NASAGSFCJefferson Beck

Antarctic Ice Shelf Loss Comes From Underneath          Photo: NASA/GSFC/Jefferson Beck

New reports published on Monday May 12 show Artic melt is happening faster than expected.

Two new pieces of research, conducted by teams of researchers from NASA and the University of Washington, have found that large sections of West Antarctic ice have already begun an ‘unstoppable thaw’ which is predicted to continue affecting water levels for centuries.

An IPCC climate change report released last month predicted that global water levels could rise as much as four feet by 2100, but did not factor in melting of the West Antarctic ice sheet, meaning that the real figure could be closer to seven feet.

The two teams of researchers worked independently but decided to publish their findings on the same day when they discovered they had come to the same conclusions. Both groups discovered that thaw in the West Antarctic ice sheet has resulted in the destabilising of the entire ice sheet, an outcome scientists have been worried about for several decades.

The findings were deemed so serious that NASA called a telephone conference on Monday May 12. As NASA’s Thomas P. Wagner, who runs the institute’s polar ice programmes and oversaw some of the research, said “This is really happening. There’s nothing to stop it now.”

However, he added that the speed of the thaw is “limited by the physics of how fast the ice can flow.” The scientists said that the rise in sea levels is likely to remain slow for the rest of this century, but in the future could accelerate suddenly, as the melting of the glaciers studied destabilises further ice sheets.

The research by NASA was conducted using 40 years of ground, aerial and satellite data, which showed that the ice in West Antarctica is collapsing faster than scientists had predicted. It has melted at such a rate that it has already reached what the scientists called “the point of no return”, setting off a domino effect across the ice sheets in the area.

The University of Washington research focused on Thwaites, one of the formation’s most important glaciers. The team, led by Ian Joughin, used computer modeling and recent ice flow measurements to track the melting of the ice.

Like NASA’s researchers, they also concluded that collapse of the ice was now inevitable. Joughin explained that “There’s no stabilisation mechanism”, which means that even if the warm water causing the current melting dissipated, it is already too late to reverse the effects.

This latest research vindicates the 1968 findings of eminent glaciologist John H.Mercer. An academic at Ohio State University, he warned that the vulnerability of the West Antarctic ice sheet combined with the rise in greenhouse gases spelled “a threat of disaster.”

His findings were derided at the time of their publication, but events appear to have unfolded as he predicted. Mercer died in 1987.

These latest reports have been criticised by some sectors as being ‘too dramatic’ but an article responding to these claims in The New Yorker argued that “it increasingly appears that, if there is any systemic bias in the climate models, it’s that they understate the gravity of the situation.”

By Charlotte Ryan