Tipping elements in the Earth's climate system

TLDR

A tipping point is a critical threshold where a small perturbation can qualitatively alter a system’s state or development. The study introduces the term “tipping element” to describe large‑scale Earth system components that may reach a tipping point and evaluates policy‑relevant candidates. The authors use expert elicitation to rank the sensitivity and uncertainty of candidate tipping elements and outline how early warning systems could detect proximity to tipping points.

Abstract

The term "tipping point" commonly refers to a critical threshold at which a tiny perturbation can qualitatively alter the state or development of a system. Here we introduce the term "tipping element" to describe large-scale components of the Earth system that may pass a tipping point. We critically evaluate potential policy-relevant tipping elements in the climate system under anthropogenic forcing, drawing on the pertinent literature and a recent international workshop to compile a short list, and we assess where their tipping points lie. An expert elicitation is used to help rank their sensitivity to global warming and the uncertainty about the underlying physical mechanisms. Then we explain how, in principle, early warning systems could be established to detect the proximity of some tipping points.