Glacier that could raise sea level by several feet ‘holding on by its fingernails’: researcher

A glacier that could cause a multi-foot sea level increase if it melted is disappearing at about twice the previously observed rate, according to a study published Monday in the journal Nature Geoscience. 

Although the findings indicate the rate of retreat has slowed in recent years, researchers also saw indications that past a certain point the recession could begin increasing rapidly again.  

“Thwaites is really holding on today by its fingernails, and we should expect to see big changes over small timescales in the future — even from one year to the next — once the glacier retreats beyond a shallow ridge in its bed,” co-author Robert Larter of the British Antarctic Survey said in a statement.  

“Just a small kick to Thwaites could lead to a big response,” added Graham. 

Researchers, led by Alistair Graham of the University of South Florida, analyzed historical data on the retreat of the Thwaites Glacier, which is about the size of Florida and considered among the most vulnerable parts of the West Antarctic Ice Sheet. They found that during a five-month period in the previous two centuries, the glacier receded at an annual rate of about 1.3 miles — twice the rate observed over the 2010s. 

While analysis of the glacier has historically been limited to the three decades of available satellite imagery, Graham and his team were able to trace its path back further based on the glacier’s imprint on the seabed.  

The Thwaites Glacier is also known as the “Doomsday Glacier” for the sea level rise its melt could cause — just over two feet. It is at particular risk due to its position on the ocean floor rather than land, making it vulnerable to warming ocean currents. 

The study comes less than a month after separate research indicating the worst impacts of climate change on the East Antarctic Ice Sheet could be held back if global temperature increases are kept below 2 degrees Celsius.