Southern Ocean Could Release Stored Heat Even After Climate Recovery

New research reveals a startling possibility: even if humanity successfully reduces global warming, the Southern Ocean surrounding Antarctica might unleash decades of stored heat back into the atmosphere, potentially restarting climate change.

Scientists describe this phenomenon as a massive oceanic “burp” that could occur once we achieve net-negative emissions and begin cooling the planet. The Southern Ocean has been acting like a giant heat sink, absorbing over 80% of the excess warmth that oceans have captured since the Industrial Revolution. According to climate modeling, this stored thermal energy won’t stay put forever.

The mechanism works like this: as atmospheric temperatures drop due to emission reductions, the ocean’s surface becomes colder and saltier from new sea ice formation. This creates an unstable water column that eventually triggers deep convection, releasing accumulated heat in what researchers call an “abrupt” event. The resulting warming could match current human-caused climate change rates and continue for at least a century.

However, this scenario isn’t guaranteed—it’s based on modeling predictions that require further study. The research underscores how little we understand about Earth’s response to negative emissions and carbon removal technologies. While the findings might sound discouraging, scientists emphasize that carbon removal would still significantly reduce global temperatures overall, even accounting for the potential heat burp. The key message remains urgent: dramatically cutting emissions now is far better than relying on future carbon removal technologies to clean up our atmospheric mess.