An Unmapped Region of Antarctica Could Be Harboring a Major Threat

A vast region of East Antarctica contains enough ice to cause a dramatic rise in global sea levels but was considered relatively stable before. Now, a new study is urging scientists to take a closer look at the Wilkes Subglacial Basin, warning that as the climate warms, this hidden Antarctic ice store could become a significant driver of future sea-level rise. The Wilkes Subglacial Basin is a huge depression in the bedrock beneath the East Antarctic Ice Sheet. Although it is one of the more important parts of Antarctica when it comes to future sea-level rise, it remains vastly unexplored. In a recent study, published in Nature Reviews Earth & Environment, scientists found that the basin’s underlying geography could cause it to become unstable as the climate warms. That’s concerning, as the basin contains enough ice to raise sea levels by up to 10 to 13 feet (3 to 4 meters). Hidden threat The Wikes Subglacial Basin stretches for roughly 870 miles (1,400 kilometers) along the inland side of the Transantarctic Mountains. It is completely hidden beneath a thick layer of ice, so scientists have had to rely on radar and satellite observations to collect data on the vast basin. “The Wilkes Subglacial Basin is arguably the last unexplored place in Antarctica,” Matt King, a professor at the University of Tasmania and lead author of the new study, said in a statement. “There’s no in situ mapping data of the sea floor, and we have very limited information about the ocean conditions that could drive future melting.” Although it was once considered one of the more stable parts of Antarctica, scientists are only now beginning to understand how vulnerable it could be. The basin is a marine-based part of the ice sheet, which means the bedrock beneath much of the ice lies below sea level. That can make the ice particularly vulnerable to retreat if warmer seawater reaches the grounding zone. The scientists behind the new study combined existing data with computer modeling to predict future changes to the region. Their findings suggest retreat could become very rapid in some areas, potentially reaching around 0.6 miles (1 kilometer) per year beyond important bedrock pinning points. If it were eventually lost, the ice contained within the region would be enough to contribute several feet of global mean sea-level rise. Sound the alarm Although East Antarctica has traditionally been regarded as considerably more stable than West Antarctica, the recent findings paint a different picture. The region’s marine-based basins mean that it could become much more important under sustained warming. As of now, however, it remains largely unstudied. The researchers behind the new study are hoping to bring more attention to East Antarctica’s Wilkes Subglacial Basin, highlighting major gaps in observations. The new paper shows that parts of the basin have already undergone change. Previous evidence points to the thinning and collapse of some of the ice shelves. The basin’s main glacier, Cook Glacier, has also been thinning at an increasing rate since the 1990s and currently sends roughly 44 billion tons (40 billion tonnes) of ice into the ocean each year, according to the researchers. “The evidence from past warm periods is enough to ring an alarm bell that this is a region we need to understand much better, but it’s hard to find a living scientist who’s been there,” King said.