Tipping points in climate science normally refer to small changes in the Earth system that unleash much broader, typically damaging impacts that accelerate climate change. Well-known examples are rising sea levels due to disintegration of the Greenland and West Antarctica ice sheets, or the release of methane from the thawing permafrost. They help to underline the urgency of climate action. Today most people understand we must reduce emissions – and very quickly.
In this webinar, Professor Lenton will summarise recent evidence regarding climate tipping points, which supports declarations that we are in a ‘climate emergency’. Then he will turn to identifying positive social tipping points that will need to be triggered to have any hope of limiting global warming to well below 2°C.
Time: 16:00 – 17:00 Beijing Time (UTC+8), September 18, 2025
Zoom ID: 86559486063
Zoom Code: 202509
Link: https://us02web.zoom.us/j/86559486063
Keynote Speaker: Timothy Lenton
Professor Timothy Lenton is the founding Director of the Global Systems Institute at the University of Exeter and Chair in Climate Change and Earth System Science. He has more than 25 years research experience, focused on modelling of the biosphere, climate, biogeochemical cycles, and associated tipping points. Timothy is renowned for his work identifying climate tipping points, which informed the setting of the 1.5C climate target, associated net zero targets, and nationally determined contributions.
Timothy works with policymakers and businesses helping them assess the risks of climate change and nature loss and highlighting the opportunities for ‘positive tipping points’ that can accelerate change towards net zero. In 2023, Professor Lenton led a team of more than 200 people from over 90 organisations in 26 countries to produce an authoritative assessment of the risks and opportunities of both negative and positive tipping points in the Earth system and society. The ‘Global Tipping Points Report’ produced in partnership with Bezos Earth Fund was published at COP28.
Panel Members: Matthew England, Steven Sherwood, Stefanie Rynders
Matthew England
Scientia Professor Matthew England completed his Bachelor of Science with First-Class Honours and the University Medal (1987) and his Doctor of Philosophy (1992), both at The University of Sydney, Australia. His research explores large-scale ocean circulation and its influence on regional and global climate, with a particular focus on the Southern Hemisphere and Antarctic climate processes. By utilizing ocean and coupled climate models alongside observations and theoretical approaches, he studies what controls ocean currents and how they affect climate variability on timescales from seasons to millennia. A highly cited researcher, his academic accomplishments are evidenced by an extensive publication record, including numerous articles in premier journals like Nature and Journal of Climate. His work has been recognized with many prestigious awards, including the Tinker-Muse Prize for Science and Policy in Antarctica (US$100,000), the NSW Scientist of the Year, and the James Cook Medal. He is an elected Fellow of several esteemed societies, including the American Geophysical Union (AGU), the Australian Academy of Science (FAA), and the Royal Society of NSW (FRSN).
Steven Sherwood
Professor Steven Sherwood completed his undergraduate degree in Physics at the Massachusetts Institute of Technology (1987) and holds an M.S. in Engineering Physics from the University of California, San Diego (1991). He earned his Ph.D. in Oceanography from the Scripps Institution of Oceanography in 1995. He is currently a Professor at the Climate Change Research Centre at UNSW Sydney, a position he has held since 2009.
His research focuses on the dynamics of clouds, convection, and water vapour, and their critical role in the climate system. His work has been instrumental in understanding atmospheric humidity, quantifying climate sensitivity, and exploring the limits of human adaptation to heat stress.
An accomplished author, he has published approximately 180 peer-reviewed papers, including several in high-impact journals like Science and Nature, and has an h-index of 50 (Scopus). His accomplishments have been recognized through numerous distinctions. He is a Fellow of the American Geophysical Union (2024) and the Royal Society of New South Wales (2016), and a recipient of the ARC Laureate Fellowship (2015-2020). His expertise is sought in major international advisory roles, notably as Co-Chair of the World Climate Research Programme's Lighthouse Activity on Safe Landing Climates.
Stefanie Rynders
Dr. Stefanie Rynders completed her undergraduate and Master's degrees in Physics at the University of Antwerp, which included a year of Erasmus Exchange studying oceanography at the University of Utrecht. She earned her PhD in 2019 in Ocean Science from the University of Southampton.
She is currently a marine model developer at the National Oceanography Centre in Southampton, United Kingdom. Her research focuses on pushing the boundaries of high-resolution ocean and sea-ice modelling, with a geographic emphasis on the Arctic and North Atlantic. Her work specifically investigates eddy effects, wave-ice interactions leading to coastal erosion, and resulting nutrient fluxes. Furthermore, her research interests encompass critical themes of climate change, including tipping points, early warning systems, and climate state reversibility under negative emissions.
Dr. Rynders' expertise has been recognized through her significant contribution to the influential 'Global Tipping Points Report', a collaboration that brought her into contact with social scientists. She has also served as a convenor and co-convenor for multiple sessions at the European Geosciences Union (EGU) assembly, including "Changes in the Arctic Ocean" and a "Great Debate" on science and policy for early-career researchers.
Post your questions to the keynote speaker and panel members：globalonce@xmu.edu.cn