Researchers determined Antarctica's Thwaites Glacier will most likely disappear within a few hundred years. This even could raise sea levels by more than two feet.
The research team used a combination of "airborne radar, detailed topography maps and computer modeling," to make their findings, a National Science Foundation news release reported.
The glacier in question acts as an "ice dam" to keep the West Antarctic Ice sheet from moving into the ocean; the sheet could contribute to an additional 10 to 13 feet of global sea level rise.
"There's been a lot of speculation about the stability of marine ice sheets, and many scientists suspected that this kind of behavior is under way," Ian Joughin, a glaciologist at the university's Applied Physics Laboratory (APL) and the first author on the paper, said in the news release. "This study provides a more quantitative idea of the rates at which the [ice sheet] collapse could take place."
The researchers determined the Thwaites glacier has been losing tens of feet of elevation every year.
"Previously, when we saw thinning we didn't necessarily know whether the glacier could slow down later, spontaneously or through some feedback," Joughin said. "In our model simulations it looks like all the feedbacks tend to point toward it actually accelerating over time; there's no real stabilizing mechanism we can see."
Using a computer model the researchers looked at the glacier's ice loss over the past 18 years. They also ran the model forward to see how different amounts of "ocean-driven" melting affected the glacier.
The grounding line, or place where the glacier meets the ground, is situated on a ridge that sits only 2,000 feet below sea level. Once the retreating glacier moves into deeper waters the ice will become steeper and eventually collapse.
"Once it really gets past this shallow part, it's going to start to lose ice very rapidly," Joughin said.
"All of our simulations show it will retreat at less than a millimeter of sea level rise per year for a couple of hundred years, and then, boom, it just starts to really go," he said.
