One of the least explored and least known regions of Antarctica contains enough ice to raise the global mean sea level by between three and four meters. This is the Wilkes Subglacial Basin, in East Antarctica, an area that researchers consider a priority to study in order to better understand the future evolution of the ice sheet and its impacts.
A new scientific review, published in Nature Reviews Earth & Environment, brings together the knowledge currently available about the region and identifies significant gaps in observations. The authors warn that, without new data, it remains difficult to determine with confidence how quickly the basin may undergo changes or which climatic conditions could trigger a large-scale retreat.
The review was led by Matt King, Professor of Polar Geodesy at the University of Tasmania and a researcher at the Australian Centre for Excellence in Antarctic Science, and brings together contributions from researchers in 14 countries. The work cross-cuts data from geology, oceanography, climate science, satellite observations and ice-sheet models.
“The Wilkes Subglacial Basin is, probably, the last unexplored site in Antarctica,” says Matt King.
The scale of the unknown is particularly evident in access to the region. According to the researcher, no ship has yet come within 150 kilometres of the front of one of its main glaciers, the Cook Glacier. There are no in situ seabed mapping data, and information about the ocean conditions that could influence future melting is also very limited.
Despite these limitations, there is evidence from geological records that the basin underwent a significant retreat during previous periods of global warming. For the researchers, this evidence is relevant to understanding how the region could respond to current and future climate changes, although it does not, by itself, determine the evolution it will have in the coming decades or centuries.
“The evidence of warm periods in the past is sufficient to sound an alarm that this is a region we need to understand much better, but it is difficult to find a researcher still active who has been there,” notes King.
The Wilkes Subglacial Basin lies largely in the Australian Antarctic Territory and is considered one of the regions important for improving sea level rise projections. The amount of ice stored there means that significant changes could have consequences far beyond Antarctica, especially for coastal areas and vulnerable infrastructure.
Therefore, the authors advocate for an internationally coordinated campaign to map the region and strengthen data collection on the ocean and the ice sheet. The aim is to reduce uncertainties about how this part of Antarctica may respond to global warming.
“If we can better understand this region and determine its evolution with greater precision, we will be better prepared for future sea level rise, for climate impacts and for the consequences for coastal communities and vulnerable infrastructure in Australia, the Pacific, and around the world,” says Matt King.
The work was developed by the Australian Centre for Excellence in Antarctic Science in collaboration with the Australian Antarctic Program Partnership and the Securing Antarctica’s Environmental Future program.
