An international team of scientists has concluded that Antarctica’s mighty Pine Island Glacier has likely reached a tipping point in which the melting is irreversible even if global warming is reversed. The research, published in the journal Nature Climate Change, is significant because the glacier is the single largest contributor to sea level rise in Antarctica. Already contributing to around 25 percent of the total ice loss from West Antarctica, scientists predict that Pine Island will increase global sea levels by as much as 10 millimeters over the next 20 years.

“The models show a strong agreement and the result is a striking vision of the near future. All the models suggest that this recession will not stop, cannot be reversed and that more ice will be transferred into the ocean,” said the paper’s lead author, Dr Gaël Durand of the French National Centre for Scientific Research.

The glacier retreat is being influenced more by warm ocean-bottom waters than higher air temperatures because a large section of the glacier’s ice shelf sits below sea level. Scientists say this produces “marine ice sheet instability” that is the major factor behind the irreversible decline.

“At the Pine Island Glacier we have seen that not only is more ice flowing from the glacier into the ocean, but it’s also flowing faster across the grounding line – the boundary between the grounded ice and the floating ice. We also can see this boundary is migrating further inland,” said Dr Hilmar Gudmundsson of British Antarctic Survey.

The massive Pine Island Glacier covers more than 160,000 square kilometers and flows alongside the Hudson Mountains and into the Amundsen Sea.

+ Nature Climate Change paper: Retreat of Pine Island Glacier controlled by marine ice-sheet instability

Via BBC News

Images via British Antarctic Survey