An international team of climate scientists has published the most comprehensive assessment of 'climate tipping points'—thresholds where small changes in temperature trigger reinforcing feedback loops.
The Domino Effect
The study identifies nine active tipping points, including the collapse of the Greenland Ice Sheet and the dieback of the Amazon Rainforest. Crucially, it models the 'teleconnections' between them: how freshwater from melting ice slows the Atlantic circulation, which in turn dries out the Amazon.
Critical Thresholds
The analysis warns that five of these tipping points, including the loss of tropical coral reefs and abrupt permafrost thaw, are likely to be crossed at 1.5°C of warming—a limit the world is rapidly approaching.
Irreversibility
Once triggered, these systems shift to a new state even if human emissions stop. For example, once permafrost thaw becomes self-sustaining (generating its own heat via bacterial decomposition), it cannot be re-frozen.
Policy Call to Action
The report argues that economic models vastly underestimate these risks. It calls for a 'state of planetary emergency' to prioritize immediate methane reduction, which is the fastest way to slow near-term warming.
