Geophysical observations show that large sectors of East Antarctica with their drainage basin grounded below sea level (marine-based)1 are more susceptible to ocean warming than previously thought, showing accelerated ice mass loss, and are vulnerable to potential tipping points due to instabilities relating to their bed configurations2-7.

The Wilkes Subglacial Basin (WSB) is the largest of the marine sectors of the East Antarctic Ice Sheet (EAIS) and has the potential to raise global sea levels by 3–4 m and impact global ocean circulation. The WSB is a 1400 km-long and up to 600 km-wide tectonic subglacial depression, of which most lies well below sea level on a retrograde bed that deepens in land. This retrograde bedslope makes this marine-based EAIS sector not only highly sensitive to melt from modified Circumpolar Deep Water (mCDW) intrusions, but also Marine Ice Sheet Instability (MISI) processes whereby once retreat is triggered it is sustained by bathymetrical controlled feedbacks8,9.

This workshop follows previous initiatives like the EA-MISI funded by the EU-POLARNET coordination project (PI: L. De Santis) funded by the EU-POLARNET coordination project (https://eu-polarnet.eu/services-ea-misi/), the Polarin proposal PIONER (Present and past Ice-Ocean Interactions in George V Land) (PI. D. Evangelinos), the already funded project ‘Paleoecological and paleoclimate reconstruction of the Cook Ice Shelf: a genomic approach’ (PI’s L. Armbrecht et al.) and seeks to build on numerous other initiatives to develop a broader international collaboration to assess the vulnerabilities of the Wilkes Subglacial Basin and its regional and global consequences. These include pending research proposals, plans for voyages into the region and the development of a review document focusing on the scientific priorities and relevant logistics requirements.

The focus of this workshop is to:

● Advance the review publication seeking broader input;

● Advance the plan for a Land2Sea IODP/ICDP proposal to be submitted in January 2026;

● Discuss and prioritise logistics requirements;

● Coordinate funding proposals to provide complementary resources;

● Develop a timeline for key initiatives and a coordinated, multi-season deployment to the region perhaps aligned with Antarctica InSync and for delivery by the 5th International Polar Year (2032-33)

This workshop is funded through MARICE-MARine and ICE core reconstruction of East Antarctic sea ice variability (PI Johan Etournau and Nancy Bertler through the Royal Society of New Zealand Catalyst Fund 19-VUW-047-DDU) and generously supported by the University of Vienna.

Wilkes Subglacial Basin - Vulnerabilities and Global Consequences