Sheffield, In the middle of the Antarctic winter, temperatures rose dramatically by up to 28°C above average in July and August 2024, staying high for more than two weeks. This was not an isolated event, but a rare atmospheric disturbance, amplified by human-caused climate change, offering a glimpse of what could become more common in the decades ahead.
A recent study showed that the Antarctica heatwave was not simply unusual weather, but a clear shift: extreme warming is no longer confined to traditionally vulnerable regions. The heatwave unfolded with a weakening of the Antarctic polar vortex, allowing unusual warming in the stratosphere, where temperatures rose by more than 15°C.
A persistent high-pressure system developed over East Antarctica, opening a pathway for a long, narrow plume of warm, moisture-rich air to move deep into the continent. This air mass transported heat from lower latitudes into the Antarctic interior – something that rarely happens in winter.
Our analysis, using computer simulations to compare today's climate with a world without human influence, shows climate change made the 2024 winter heatwave both stronger and more likely. Such extreme weather would have been exceptionally rare in the past, but today it is already significantly more likely – and could become up to 20 times more frequent by the end of the century under high emissions.
A heatwave in Antarctica might seem remote from everyday life, but what happens there has global consequences. Antarctica holds most of the world's freshwater, locked in vast ice sheets. Even short-lived warming events can influence snowfall, surface melt and the stability of floating ice shelves that hold back glaciers.
