Complex systems and Biological physics seminar [before December 2013]

Early warning of critical transitions in nature and society

by Steven Lade (Stockholm Resilience Centre, SU)

Europe/Stockholm
Description
A wide variety of systems in nature and society -– including fisheries, coral reefs, productive farmland, planetary climate, neural activity in the brain, and financial markets -– are known to be susceptible to sudden changes leading to drastic re-organization or collapse. A variety of signals based on statistics of time-series data have been proposed that could provide generic warning signals for these so-called critical transitions. In this talk, I will propose a new method for calculating early warning signals that is complementary to existing approaches. The key step is to incorporate other available expert knowledge through the framework of a so-called generalised model. The eigenvalues of the generalised model then constitute the early warning signal. The new approach will be demonstrated through application to three ecological examples, including the simulated collapse of a fishery.