Thresholds of Irreversible Retreat Identified on Major Portion of West Antarctic Ice Sheet

Kryosfären, March 25

Located in the West Antarctic Ice Sheet, Pine Island is currently the fastest melting glacier in Antarctica and accounts for a quarter of all ice lost in the region. Three distinct thresholds or tipping points, rather than one single event, were identified for the Pine Island Glacier in response to increases in ocean-induced melt. The crossing of a threshold could easily be misinterpreted as a period of fast retreat, while in reality, the glacier will have entered a phase of retreat resulting in irreversible and rapid ice loss. The first and second thresholds are relatively small, but could still lead to considerable sea-level rise, with a low chance of recovery. The third and final threshold, triggered by an ocean warming of approximately 1.2°C, will lead to the retreat of the entire Pine Island Glacier, which could initiate the collapse of the entire West Antarctic Ice Sheet. This alone would result in over three meters of global sea level rise, with catastrophic consequences for coastal regions across the world.

https://tc.copernicus.org/articles/15/1501/2021/

Compiled by Amy Imdieke