Tipping Elements in the Earth System

Tipping elements are a growing area of research into the nonlinear behavior of the climate system. The Intergovernmental Panel of Climate Change (IPCC) Special Report on the Ocean and Cryosphere in a Changing Climate defined a “tipping point” as “a level of change in system properties beyond which a system reorganizes, often in a non-linear manner, and does not return to the initial state even if the drivers of the change are abated. For the climate system, the term refers to a critical threshold at which global or regional climate changes from one stable state to another stable state.” Tipping elements are further defined as a subsystem of the climate system that could be experiencing a tipping point (e.g. Atlantic Meridional Overturning Circulation, Amazon Rainforest, permafrost, Greenland Ice Sheet, etc.). Here we feature a series of online discussions convened by AIMES, Future Earth, Earth Commission, and WCRP Safe Landing Climates Lighthouse that aim to advance knowledge about tipping elements, irreversibility, and abrupt changes in the Earth system. This series is ongoing and you can sign up for future events here.

Introduction to the Tipping Elements in the Earth System Webinar Series.

Speakers: Steven Sherwood (CCRC), Ricarda Winkelmann (PIK), Tim Lenton (University of Exeter), Sonia Seneviratne (ETH Zurich)

Date aired: 20 September 2021

About: The first event in the series provides an overall introduction. Steven Sherwood and Ricarda Winkelmann introduce the series and its objectives. Tim Lenton presents an update on tipping elements in the climate system. Sonia Seneviratne presents insights from IPCC AR6, including extreme events in a changing climate. The talk is followed by questions and discussion. The next discussions will then dive into one Earth system tipping element in detail, i.e., Amazon rainforest, ice sheets.

Amazon: Tipping Elements, Irreversibility, and Abrupt Change

Speakers: Tim Lenton (University of Exeter), Patricia Pinho (University of São Paulo), Carlos Nobrel (University of São Paulo), Peter Cox (University of Exeter)

Date aired: 19 November 2021

About: This event focused on the Amazon. Introduction and moderation was facilitated by Tim Lenton and Patricia Pinho. Carlos Nobrel presented his talk: Is the Amazon Rainforest near a Tipping Point? Peter Cox led his presentation on Amazon Forest dieback in CMIP6 Earth System Models. The webinar was concluded with questions and a discussion.

Permafrost: Tipping Elements, Irreversibility, and Abrupt Change

Speakers: Victor Brovkin (Max Planck Institute for Meteorology), Hanne Hvidtfeld Christiansen (UNIS), Gustaf Hugelius (Stockholm University)

Date aired: 17 January 2022

About: This event focused on permafrost. Victor Brovkin introduced the webinar and its objectives of the webinar. An update on permafrost tipping was given by Hanne Hvidtfeld Christiansen. Gustaf Hugelius presented on Model insight on permafrost change. The webinar concluded with questions and discussion.

Ice Sheets: Tipping Elements, Irreversibility, and Abrupt Change

Speakers: Heiko Goelzer (University of Utrecht), Hannah Liddy (AIMES), Sophie Nowicki (University at Buffalo), Ricarda Winkelmann (PIK)

Date aired: 25 January 2022

About: This event focused on the ice sheets. Heiko Goelzer and Hannah Liddy moderated and itnroduced the event. Sophie Nowicki talked about Projections from the Greenland and Antarctic ice sheets: insights from IPCC AR6. Ricarda Winkelmann’s presentation was called Beyond gradual change: Tipping points in Greenland and Antarctica. The webinar concluded with questions and discussion.

Ocean: Tipping Elements, Irreversibility, and Abrupt Change

Speakers: Helene Hewitt (Met Office Hadley Center), Didier Swingedouw (University of Bordeaux), Christoph Heinze (University of Bergen), Stefan Rahmstor (Potsdam Institute for Climate Impact Research)

Date aired: 11 February 2022

About: This event focused on oceans. Helene Hewitt and Didier Swingedouw moderated the event. An overview of ocean tipping points was given by Christoph Heinze. Recent insights on AMOC were presented by Stefan Rahmstorf. The talks were followed by a question and answer session.

Monsoon Systems: Tipping Elements, Irreversibility, and Abrupt Change

Speakers: Hindumathi Palanisamy (WCRP), Martin Claussen (Max Planck Institute for Meteorology), Ashwin Seshadri (DCCC, CAOS), Francesco Pasata (UQAM)

Date aired: 9 March 2022

About:  This event focused on monsoon systems: Hindumathi Palanisamy and Martin Clausse moderated the event. An update on South Asian Monsoon tipping was given by Ashwin Seshadri. A presentation on African Monsoon and potential greening of the Sahara was given by Francesco Pausata. The event concluded with Q&A and discussion.

Human and Earth Systems Interlinkages

Speakers: Richard Hornbeck (University of Chicago) and Michelle Mycoo (The University of the West Indies)

Date aired: 7 April 2022

About: The seventh webinar by AIMES and the Earth Commission (Future Earth), and the WCRP Safe Landing Climates Lighthouse Activity looks at the interlinkages between Earth and social systems in relation to tipping elements, irreversibility, and abrupt changes in the Earth system. The event included two presentations from world leading researchers discussing historic and contemporary examples of how Earth system tipping elements affect societies and the people within them. Presentation themes consist of the Dust Bowl and Earth System Change and Tipping: The Case of Small Island Developing States. The webinar was moderated by Gabi Hegerl, Climate System Science, School of Geosciences, University of Edinburgh and Caroline Zimm, International Institute for Applied Systems Analysis (IIASA). Link to the online event page: https://tipping-series-interlinkages….

    Tipping towards positive social change

    Speakers: J. Doyne Farmer (University of Oxford), Prof. Ilona Otto (University of Graz)

    Date aired: 12 May 2022

    About: This event includes two presentations on socioeconomic tipping for achieving positive change: “Social tipping dynamics” and “What are the sensitive intervention points needed to make the green energy transition happen as quickly as possible?” The event was moderated by Jonathan Donges (Potsdam Institute for Climate Impact Research). The presentations were followed by a Q&A and discussion. Input collected can be found on the MIRO board. 

      Want to Learn More?

      If you are interested in tipping elements, take a look at our webpage for the Tipping Elements in the Earth System Working Group. You’ll find our webinar series as well as recent developments in the field.