A climate threat may lurk beneath Antarctica's last great unknown

A region of Antarctica with some of the greatest potential to reshape the natural world and human society is also the least scientifically understood and explored.

A new global review paper published in Nature Reviews Earth & Environment is calling for a coordinated global campaign to study East Antarctica's Wilkes Subglacial Basin. One of the most important regions on Earth for predicting future sea-level rise, it contains enough ice to raise global mean sea levels by an estimated 3 to 4 meters (10–13 feet).

Led by Matt King, a professor at the University of Tasmania and chief investigator at the Australian Center for Excellence in Antarctic Science, the review synthesizes findings from geology, oceanography, climate science, satellite observations and ice-sheet modeling to assess what scientists know, and don't know, about the vast ice-filled basin.

The review concludes that major gaps in observations mean scientists still cannot confidently predict how rapidly change could occur or what climate thresholds might trigger large-scale retreat.

Unmapped waters and signs of past retreat

"The Wilkes Subglacial Basin is arguably the last unexplored place in Antarctica," King said.

"No ship has ever been within 150 kilometers (93 miles) of the front of one of the key glaciers, the Cook Glacier. 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."

Despite these major knowledge gaps, evidence from geological records suggests the basin, located largely within Australian Antarctic Territory, has undergone substantial retreat during past warm periods, raising questions about how it may respond to future climate change.

"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.

An international push to close knowledge gaps

The review was co-authored by researchers from 14 countries and calls for an urgent international response to map the region, improve ocean and ice-sheet observations, and reduce uncertainty about future climate and sea-level impacts.

"If we can better understand this region and its trajectory more accurately, we'll be better prepared for future sea-level rise, climate impacts and the consequences for coastal communities and vulnerable infrastructure in Australia, the Pacific and around the world," King said.