Climate tipping point
A threshold beyond which a change can become self-sustaining or lead to a different state of a system.
Example
Ice sheets and ecosystems may respond nonlinearly as conditions change.
The catch
Thresholds and timescales are uncertain; a precise countdown needs strong evidence.
Related terms
Ecosystem, Albedo, Atmospheric lifetime, Carbon budget, Carbon dioxide, Climate change
In more depth
Climate tipping point, explained.
Climate tipping points concern large parts of the Earth system, including the Greenland and West Antarctic ice sheets, the Atlantic overturning circulation and the Amazon rainforest. The IPCC treats several as low-likelihood, high-impact outcomes whose risk rises with each increment of warming. Some would unfold over centuries once triggered, yet still be irreversible on any timescale that matters to people alive today.
Crossing one would not make further action pointless, and treating it that way is climate fatalism. Every avoided increment of warming still lowers the risk of triggering others and slows the damage. A social tipping point borrows the idea for the spread of new behaviours and technologies, which is the same mechanism working in climate action's favour.