A recent study published in Nature Geoscience determined that vulnerabilities exist in the large ice sheet of East Antarctica - in addition to those found in the western part of Antarctica.
East Antarctica’s Totten Glacier is similar to the glaciers of West Antarctica in that its root is located deep below the surface of the water. Scientists now think that the glacier’s deep roots below sea level may possibly explain why the glacier has thinned out and lost elevation over time.
Totten Glacier is located along East Antarctica’s Sabrina Coast and holds back over 12 feet of potential rise in sea level.
Xin Li, a researcher at the University of California, Irvine, worked with researchers at NASA’s Jet Propulsion Laboratory to examine Totten Glacier by using aircraft data and satellite imagery. For the first time, researchers were able to document how much the glacier has retreated inland over the past several years.
Scientists determined that the glacier has moved significantly. Between 1996 and 2013, the glacier’s grounding line (the critical underwater area where bedrock, ice and the ocean meet) retreated as much as almost two miles in some places. And, while that is fast, it is not as fast as what is occurring in West Antarctica, where some areas have retreated as much as one to two miles per year.
With respect to Totten’s grounding line, Li said that, “This boundary is very important because that’s where the ice detaches from the bed and becomes afloat and frictionless.” So, any change along the glacier’s grounding line is not good news.
Researchers sought to answer the question of whether the grounding line of Totten means a “marine ice sheet instability” exists in East Antarctica as it does in West Antarctica.
The study suggests that the answer is negative. Li stated that, “Immediately upstream of the grounding line there is a [4.3 mile] long region — we call it an ice plain because the slopes are really flat, and for this part of the glacier, it could retreat very fast, in a couple of decades or so.” After that, though, the elevation actually rises for about 25 miles, and so the retreat would not happen as fast.
The research on Totten Glacier indicates that West Antarctica is likely the most important place that people should be worried about possibly delivering a significant rise in sea level during a time period that is relevant to the people that are alive today.