Key Part of Antarctica Doomed to "Inevitable" Melting Regardless of Climate Action Scale

As a new study reveals, no matter how much the world reduces carbon emissions, a crucial and significant section of Antarctica is essentially doomed to "inevitable" melting.

While complete melting will take hundreds of years, gradually raising sea levels by almost 6 feet (1.8 meters), it will be enough to change where and how people will live in the future, said the lead author of the study.

Researchers used computer modeling to calculate the future melting of protective ice shelves protruding over the Amundsen Sea in West Antarctica. The study, published on Monday in the journal Nature Climate Change, showed that even if future warming is limited by just a few tenths of a degree (an international target that many scientists believe is unlikely to be achieved), there will be "limited power to prevent ocean warming, which could lead to the disintegration of the West Antarctic Ice Sheet."

"Our main question was, how much can we still control the melting of the ice shelves? How much melting can still be prevented by reducing emissions?" said the lead author of the study, Caitlin Noten, an oceanographer with the British Antarctic Survey. "Unfortunately, it's not very good news. Our modeling shows that we are now committed to rapid ocean warming and ice shelf melting for the remainder of the century."

While past research has spoken to the grimness of the situation, Noten was the first to use computer modeling to study a crucial component of ice shelf melting, the warming water that melts ice from below, while considering four different scenarios of how much carbon dioxide the world pumps into the atmosphere. The study revealed that in each case, ocean warming was too strong for this section of the ice sheet to survive.

Noten has been watching the melting ice shelves that float above the ocean in this part of Antarctica, which already sits below sea level. As these ice shelves melt, nothing can stop the glaciers behind them from flowing into the sea.

Noten specifically examined what would happen if somehow future warming were limited to 1.5 degrees Celsius (2.7 degrees Fahrenheit) compared to mid-19th-century levels (an international target) and still found an unrestrained process of melting. The world has already warmed by about 1.2 degrees Celsius (almost 2.2 degrees Fahrenheit) since pre-industrial times, and much of this summer temporarily exceeded the 1.5-degree benchmark.

The study by Noten focused on that part of the West Antarctic Ice Sheet most vulnerable to bottom melting near the Amundsen Sea. It includes the massive Thwaites Ice Shelf, which is melting so quickly it's been nicknamed the "Doomsday Glacier." "West Antarctica is only one-tenth of the southern continent, but it's less stable than the larger eastern part.

This part of Antarctica is "doomed," said Eric Rignot, a glaciologist at the University of California, Irvine, who was not involved in the study. "The damage is done."