A groundbreaking study reveals that Antarctica’s once-stable sea ice is now on a fast track to collapse—driven by an unseen ocean salinity shift and a dangerous feedback loop.
There was an accelerated loss of sea ice volume last month in the #Arctic. We are not far from a record low.
Each line represents one year from 1979 [dark blue] to 2023 [dark red]. This year is shown in yellow – now updated through all of August 2024
https://t.co/qXpJKsAzX9 pic.twitter.com/FMqNnJUcwH— Zack Labe (@ZLabe) September 10, 2024
Antarctic sea ice update 🌊🧊
Antarctic sea ice reached its max winter extent of 17.16 million sq km (6.62 million sq miles) on Sept. 19, 2024. This is the second-lowest winter max on record, @NSIDC reports, just above last year. pic.twitter.com/Z0vkotNu3W
— NASA Earth (@NASAEarth) October 3, 2024
A Question of Water Salinity
Researchers at the University of Southampton found that, as Antarctic ice melts, the Southern Ocean’s surface is growing saltier. Saltier water lets deep-ocean heat rise and melt ice from below. “Less ice means more heat, which means even less ice,” says Alessandro Silvano. This flip in stratification overturns decades of assumptions that Antarctic ice would hold steady.
The Southern Ocean is undergoing profound changes that threaten to accelerate the melting of ice in Antarctica. © Alberto Naveira Garabato, University of Southampton
Upheavals Predicted in Antarctica and Beyond?
Satellite and robotic probe data show this salinity surge coincides with the reappearance of the massive Maud Rise polynya—an open-water hole unseen since the 1970s. Coauthor Alberto Naveira Garabato warns that these shocks could make current climate models obsolete. He urges continuous monitoring to grasp how the ice–ocean system will evolve.
Where Does This Giant Hole, Twice the Size of Switzerland, Come From?
The Maud Rise polynya’s return underscores the extraordinary nature of today’s Antarctic conditions. If this trend of warmer, saltier waters continues, it could permanently reshape the Southern Ocean—and with it, global climate patterns. Scientists now race to understand this hidden mechanism under our feet before it pushes Antarctic ice past a tipping point.
Nathalie Mayer
Journalist
Born in Lorraine on a freezing winter night, storytelling has always inspired me, first through my grandmother’s tales and later Stephen King’s imagination. A physicist turned science communicator, I’ve collaborated with institutions like CEA, Total, Engie, and Futura. Today, I focus on unraveling Earth’s complex environmental and energy challenges, blending science with storytelling to illuminate solutions.