Southern Ocean storms help oceans absorb excess heat and mask future warming

by Robert Schreiber
Gothenburg, Sweden (SPX) Dec 17, 2025
Researchers at the University of Gothenburg report that intense storms over the Southern Ocean enhance vertical mixing, allowing this ocean to absorb more heat from the atmosphere and moderate global warming. The Southern Ocean surrounds Antarctica and helps regulate Earth's climate by transporting heat, carbon, and nutrients into the global ocean, and currently takes up more than 75 percent of the excess heat produced by human activity.

The new study in Nature Geoscience shows that strong storm winds churn the water column, pulling colder water upward and pushing warmer surface water downward. This process keeps the ocean surface cooler so it can continue to take up heat from the atmosphere.

"Our research shows that summers with stronger storm activity generate lower surface temperatures across the Southern Ocean. Hence, a stormy ocean can absorb more heat from the atmosphere, then in calm weather," says Marcel du Plessis, Researcher in oceanography at the University of Gothenburg and main author of the study. The amount of heat absorbed by the Southern Ocean influences land temperatures, the extent of sea ice, and the intensity of marine heatwaves.

By examining storm patterns around Antarctica over recent decades, the team links changes in storm intensity and windiness to climate change and shifts in atmospheric circulation. Observations show that these storms are strengthening as the atmospheric pressure contrast between Antarctica and the subtropics increases.

The researchers conclude that many climate models underestimate the strength of Southern Ocean storms and thus simulate a surface ocean that is too warm. "That is why our findings are important, because a better representation of storm processes is essential for more accurate future climate projections," says Marcel du Plessis.

Fieldwork in the Southern Ocean is logistically demanding, so the study relied on a combination of autonomous underwater and surface robots that measured temperature, salinity, and atmospheric conditions above the waves. The team combined these robotic data with multi-year model output and satellite observations to separate and quantify how storms affect ocean - atmosphere heat exchange.

"This is the first time we can clearly link Southern Ocean storms to changes in ocean warming and our climate variability over the past 20 years. Such results mean we can better understand how the ocean is warming today and thereby predict how our Earth's climate may change in the future", says Sebastiaan Swart, Professor of Oceanography at the University of Gothenburg. The study finds that storm impacts on heat uptake are strongest in the Antarctic summer, while different processes dominate in winter, which the researchers identify as a key target for future observations.

Research Report:Southern Ocean summer warming is regulated by storm-driven mixing