Evidence suggests that, under the right conditions of environmental change, a local ecosystems can pass through a tipping point and rapidly switch between stable states. This has led some to suggest that the biosphere of the entire planet can behave in the same way and that global tipping points exist.
This fascinating and intriguing idea has important implications if proved correct but how well does it stand up to calls for supporting evidence and a description of mechanisms? And what research do we need to carry out in order to find the necessary evidence?
As a basis for thinking about these questions, Trends in Ecology & Evolution has published three articles in a Focus Issue on global tipping points. Two Opinion articles set out the opposing arguments for and against while a Forum article provides an introduction and overview. This associated Cell Press Discussion extends and expands opportunities for open and public discussion of the science of tipping points and planetary boundaries.
The cases for and against followed by the overview:
Multiscale regime shifts and planetary boundaries by Terry P. Hughes, Stephen Carpenter, Johan Rockström, Marten Scheffer, Brian Walker
Does the terrestrial biosphere have planetary tipping points? by Barry W. Brook, Erle C. Ellis, Michael P. Perring, Anson W. Mackay, Linus Blomqvist
- On the origin of planetary-scale tipping points by Timothy M. Lenton, Hywel T.P. Williams