Planetary Tipping Systems

Climate tipping points are critical thresholds in Earth’s climate system where a small additional change triggers a self-perpetuating, often irreversible shift to a new state. Science now recognizes approximately 25 tipping systems—from collapsing ice sheets to dying coral reefs—with temperature thresholds that may be crossed at current warming levels (~1.47°C). Coral reefs are confirmed as the first tipping point crossed. Under current policies, there is roughly a 62% average probability of triggering major tipping points. Crossing one can cascade into others, potentially committing the planet to several metres of sea level rise, rainforest dieback, and disrupted ocean circulation.

Yet this is not settled fate. Because these thresholds are real, every tonne of emissions we avoid in the years just ahead carries outsized value: the danger climbs with each tenth of a degree of warming, and falls again with each tenth we hold back. The most reliable way to keep these doors closed is to cut emissions deeply and soon, rather than overshoot the safe range and gamble on pulling carbon back out later. The future is not a single trajectory but a choice we are still making—see how different paths could unfold in the Corridor of Life, where you can choose your future and watch the odds shift with it. And the will is already here: nearly nine out of ten people worldwide want their governments to do more—most of us simply underestimate how many others feel the same.

See About & Sources for full references and methodology.