Abrupt Climate Change in an Oscillating World.

• Published in: Scientific Reports
• Main Authors: Bathiany, S, Scheffer, M, van Nes, EH, Williamson, MS, Lenton, TM
• Format: Article in Journal/Newspaper
• Language: English
• Published: Nature Publishing Group 2018
• Subjects: Climate and Earth system modelling; Climate sciences; Environmental impact; Theoretical ecology; Climate change; Sea ice
• Online Access: http://hdl.handle.net/10871/32556; https://doi.org/10.1038/s41598-018-23377-4

This is the final version of the article. Available from Nature Publishing Group via the DOI in this record. The notion that small changes can have large consequences in the climate or ecosystems has become popular as the concept of tipping points. Typically, tipping points are thought to arise from a loss of stability of an equilibrium when external conditions are slowly varied. However, this appealingly simple view puts us on the wrong foot for understanding a range of abrupt transitions in the climate or ecosystems because complex environmental systems are never in equilibrium. In particular, they are forced by diurnal variations, the seasons, Milankovitch cycles and internal climate oscillations. Here we show how abrupt and sometimes even irreversible change may be evoked by even small shifts in the amplitude or time scale of such environmental oscillations. By using model simulations and reconciling evidence from previous studies we illustrate how these phenomena can be relevant for ecosystems and elements of the climate system including terrestrial ecosystems, Arctic sea ice and monsoons. Although the systems we address are very different and span a broad range of time scales, the phenomena can be understood in a common framework that can help clarify and unify the interpretation of abrupt shifts in the Earth system. This work was carried out under the program of the Netherlands Earth System Science Centre (NESSC), financially supported by the Ministry of Education, Culture and Science (OCW). We are grateful to Chris Huntingford for his constructive comments that helped us to improve the manuscript. We would also like to acknowledge Michel Crucifix, Henk Dijkstra, and Peter Cox for their helpful comments. S.B. is eternally grateful to Nina Engelhardt and the University of Edinburgh for the inspiring working conditions.