Rapid thinning of Pine Island Glacier may continue for decades to come

A new study has suggested that the largest single contributor to global sea level rise, Pine Island Glacier (PIG), a glacier of the West Antarctic Ice Sheet, may continue thinning for decades to come.

The team of Geologists from the UK, USA and Germany said their findings demonstrate the potential for current ice loss to continue for several decades yet.

Their findings reveal that 8000 years ago the glacier thinned as fast as it has in recent decades, providing an important model for its future behaviour. The glacier is currently experiencing significant acceleration, thinning and retreat that is thought to be caused by 'ocean-driven' melting; an increase in warm ocean water finding its way under the ice shelf.

After two decades of rapid ice loss, concerns are arising over how much more ice will be lost to the ocean in the future.

Rocks exposed by retreating or thinning glaciers provide evidence of past ice sheet change, which helps scientists to predict possible future change.

The geologists used highly sensitive dating techniques, pioneered by one of the team, to track the thinning of PIG through time, and to show that the past thinning lasted for several decades.

Lead author Joanne Johnson from the British Antarctic Survey (BAS) said: "Our geological data show us the history of Pine Island Glacier in greater detail than ever before. The fact that it thinned so rapidly in the past demonstrates how sensitive it is to environmental change; small changes can produce dramatic and long-lasting results. Based on what we know, we can expect the rapid ice loss to continue for a long time yet, especially if ocean-driven melting of the ice shelf in front of Pine Island Glacier continues at current rates,"

The study was published in the journal Science.