Scientists say the failure of sea ice to form in a patch of ocean the size of France is a visible signal of a regional climate system that is changing faster than seasonal baselines predicted.
The Bellingshausen Sea—on the west side of the Antarctic Peninsula, where winter sea ice should by now be locking the coast in ice—was almost completely open water in June. Roughly 650,000 square kilometers of ice that should have formed was simply not there, satellite observations show. The expanse of open ocean is about the size of France, and it is happening in the season when this particular sea is supposed to be at its most frozen.
"I'm concerned. It's depressing," said Dr. Will Hobbs, an Antarctic sea ice expert at the University of Tasmania with the Australian Antarctic Program Partnership. "It is remarkable that we are in June, and there is no sea ice there." He said this was the third time in four years that sea ice had been very low in the region. "I don't think we will see sea ice there any more. It's done," he said. Hobbs said the loss of sea ice was likely linked to changes in the ocean and that scientists were trying to understand whether global heating was a factor.
Antarctic winter sea ice normally expands rapidly around the continent and peaks in September. June is the point in the seasonal cycle when the ice should be solidly established across the Bellingshausen—not vanishing from it. The anomaly is not a single bad season. It is a pattern that scientists say is becoming impossible to dismiss as noise.
The consequences of missing sea ice extend well beyond the open water itself. The Bellingshausen coast sits adjacent to the Pine Island and Thwaites glaciers—West Antarctica's largest contributors to global sea level rise, according to scientists monitoring the region. When sea ice is present, it buffers these glaciers' floating ice shelves from ocean swells and warmth. When it disappears for extended periods, those shelves lose a winter protective layer they historically relied upon.
"Just to the area's west were the Pine Island and Thwaites glaciers—the continent's major contributors to ice loss and sea level rise," said Dr. Phil Reid, who monitors Antarctic conditions at Australia's Bureau of Meteorology. Floating ice shelves in front of the glaciers could break up faster if protective sea ice is absent for longer periods, he said, and this could then speed up the loss of ice from the glaciers, pushing up global sea levels in the future.
The sea ice loss also carries ecological stakes. The Bellingshausen region is important for krill—a critical part of the food web for species in the area. Krill would normally be hiding from predators under the ice in winter, where they graze on algae. Without that ice cover, the species that depend on them face additional stress. Dr. Peter Fretwell, a scientist at the British Antarctic Survey who has been documenting penguin decline in the region, said the current loss of sea ice was "a serious problem for penguins, especially emperors." "Sea ice is forming too late and breaking up too early," he said. "It leads to reduced breeding success and longer trips to molting grounds." That framing aligns with a catastrophic breeding failure in late 2022, when thousands of emperor penguin chicks died in four colonies due to record-low sea ice—an event that contributed to the species being reclassified as "endangered" on the international threatened species list earlier this year.
A heatwave over the Antarctic Peninsula pushed daytime temperatures to 15.4 degrees Celsius at Argentina's Esperanza base on June 5—more than 20 degrees Celsius above the long-term average for that time of year, and a new June temperature record for the site. The previous June record of 13.3 degrees Celsius had stood since 1998. Hobbs said that while nobody had done the formal analysis, it was reasonable to suggest the heatwave was made worse by the lack of sea ice; open ocean absorbs more heat than reflective ice, and sea ice would normally help cool any warmer airflow entering the region from the north. Researchers are still working to determine the extent to which the missing ice and the warmth are directly linked, but the coincidence of both events in the same area in the same season is not random, they say.
On June 10, there was about 11.4 million square kilometers of sea ice around the entire continent, compared to a long-term average for that date of 12.6 million square kilometers. The global figure masks regional extremes: the Bellingshausen anomaly is far more severe than the continent-wide deficit suggests.
The question of what this means for the pace of Antarctic change is where scientists draw their sharpest caveats. Antarctic sea ice has been volatile in recent years, with record lows in 2023 and partial recoveries since. One anomalous June is a data point. Three-out-of-four failed winters is a trend—and trends are what signal system behavior, not single snapshots. The WIRED reporting that surfaces this story stops short of declaring a new baseline, but the researchers quoted do not hedge the direction of the signal: the ice is disappearing faster than the seasonal clock predicted, and the consequences for what lies behind it are already beginning to come into view.
What scientists are watching now is whether the coming austral spring and summer bring conditions that partially reset the system—or whether the 2026 winter failure joins the three that preceded it as another data point in a pattern that is becoming the new normal for the Bellingshausen Sea.
Sources: WIRED — "West Antarctica Is Missing Way Too Much Ice" reporting on satellite observations and interviews with Dr. Will Hobbs (University of Tasmania / Australian Antarctic Program Partnership), Dr. Phil Reid (Australia's Bureau of Meteorology), and Dr. Peter Fretwell (British Antarctic Survey). Antarctic sea ice extent data compared against 1991–2020 long-term average. Penguin breeding failure documented by the British Antarctic Survey.