Tipping Points in the Earth System

There is mounting evidence that some parts of the Earth system may be at risk of abrupt and potentially irreversible changes, driven by the cumulative impact of incremental global warming. Such a non-linear transition could be triggered if a critical threshold in global temperature – a “tipping point” – is crossed, when a small change could push a system into a completely new state, with potentially catastrophic impacts. In this technical briefing, we will first define tipping points and tipping elements, then explore several tipping elements in more detail and discuss the questions of abruptness, irreversibility, timescales and uncertainties for each of them. We also investigate the possibility of developing early warning systems for tipping points, and the risk of cascades of interacting tipping points, where one tipping point could trigger another.