A peer-reviewed study in Nature warns that the rapid decline of Antarctic sea ice has become a self-reinforcing climate tipping point, with consequences that may be impossible to reverse even if global temperatures stabilise. Led by Nerilie Abram of the Australian National University and the Australian Antarctic Division, the review synthesises observational data, ice cores and ship logbooks to chart changes across the continent’s ice, oceans and ecosystems. Satellite records show Antarctic sea-ice cover has shrunk an average 120 kilometres from the shoreline since 2014, a contraction occurring three times faster than the long-term loss in the Arctic. The authors say the retreat diminishes the region’s reflective surface, absorbs more solar heat and weakens the Antarctic Overturning Circulation—an ocean current vital to distributing heat and nutrients worldwide. The feedback loop threatens to accelerate melting of grounded ice shelves and the West Antarctic Ice Sheet, which alone holds enough water to raise global sea levels about three metres. The paper adds that complete destabilisation of Antarctica’s ice sheet under extreme warming could lift oceans by roughly 58 metres, while the loss of sea ice is already pushing species such as emperor penguins and krill toward potential extinction. Abram and co-authors conclude that only rapid and deep cuts to greenhouse-gas emissions over the next decade can limit further abrupt changes. Failing to keep warming close to 1.5 °C, they warn, would lock in higher seas and cascading impacts that could last for generations.