LONDON: Scientists from Imperial College London have revealed that the melting and thinning of Totten Glacier in East Antarctica is being accelerated by a valley underneath the ice shelf channeling warm water to the base of the glacier.
The research was published this week in Nature Geoscience after a collaboration with institutions in the US, Australia and France. Satellite data had previously showed that the Totten Glacier has been thinning significantly.
Described as East Antarctica’s most rapidly changing glacier, the ice shelf is around 150 kilometres long by 30 kilometres wide. It is a major outlet for the East Antarctic Ice Sheet, the largest mass of ice on Earth, which covers 98% of the continent.
It was previously believed to be relatively stable compared to the smaller West Antarctic Ice Sheet, which loses more than 150 cubic kilometres of ice every year.
Surveying the area with radar and other geophysical techniques, the team of researchers generated a map of the topographical landscape underlying the glacier.
Instead of the cooler waters previously thought to surround the East Antarctic Ice Sheet, the data revealed a 5 kilometre wide valley running underneath the glacier, which exposes the base of the ice to warm ocean water.
This intrusion of warmer water is accelerating the thinning of the ice shelf. While the thin ice at the edges of ice sheets can float on the ocean, inland ice is ‘grounded’ and in contact with the bedrock.
