Past abrupt changes, tipping points and cascading impacts in the Earth system

Brovkin, Victor [Max Planck Institute for Meteorology] Brook, Edward [Oregon State University] Williams, John W. [University of Wisconsin-Madison] Bathiany, Sebastian [Climate Service Center Germany (GERICS)] Lenton, Timothy M. [University of Exeter] Barton, Michael [Arizona State University] DeConto, Robert M. [University of Massachusetts] Donges, Jonathan F. [Potsdam Institute for Climate Impact Research] Ganopolski, Andrey [Potsdam Institute for Climate Impact Research] Crucifix, Michel [UCL] Vanderveken, Lilian [UCL] et al.[show all]

The geological record shows that abrupt changes in the Earth system can occur on timescales short enough to challenge the capacity of human societies to adapt to environmental pressures. In many cases, abrupt changes arise from slow changes in one component of the Earth system that eventually pass a critical threshold, or tipping point, after which impacts cascade through coupled climate–ecological–social systems. The chance of detecting abrupt changes and tipping points increases with the length of observations. The geological record provides the only long-term information we have on the conditions and processes that can drive physical, ecological and social systems into new states or organizational structures that may be irreversible within human time frames. Here, we use well-documented abrupt changes of the past 30 kyr to illustrate how their impacts cascade through the Earth system. We review useful indicators of upcoming abrupt changes, or early warning signals, and provide a perspective on the contributions of palaeoclimate science to the understanding of abrupt changes in the Earth system.