The current pace of global heating risks unleashing “rapid and unstoppable” sea level rise from the melting of Antarctica’s vast ice sheet, a new research paper has warned.
Unless planet-heating emissions are swiftly reduced to meet the goals of the Paris climate agreement, the world faces a situation where there is an “abrupt jump” in the pace of Antarctic ice loss around 2060, the study states, fueling sea level rise and placing coastal cities in greater peril.
“If the world warms up at a rate dictated by current policies we will see the Antarctic system start to get away from us around 2060,” said Robert DeConto, an expert in polar climate change at the University of Massachusetts and lead author of the study. “Once you put enough heat into the climate system, you are going to lose those ice shelves, and once that is set in motion you can’t reverse it.”
DeConto added: “The oceans would have to cool back down before the ice sheet could heal, which would take a very long time. On a societal timescale it would essentially be a permanent change.”
This tipping point for Antarctica could be triggered by a global temperature rise of 3C (5.4F) above the preindustrial era, which many researchers say is feasible by 2100 under governments’ current policies. The new research, published in Nature, finds that ice loss from Antarctica would be “irreversible on multi-century timescales” should this happen, helping raise the world’s oceans by 17cm to 21cm (6.69in to 8.27in) by the end of the century.