Tipping Elements in the Earth's Climate System

Sophie Hebden is a Climate Applications Scientist at the European Space Agency (ESA), specializing in land surface processes and the terrestrial carbon and water cycles. She leads a portfolio of research and development projects under ESA's Climate Change Initiative, producing satellite-based climate data records at the global scale. Previously, she worked with Future Earth, where she coordinated Earth observation-focused projects and workshops. Since 2019, she has served as a coordinating author of the annual 10 New Insights in Climate Science report. Sophie holds a Ph.D. in Space Physics from the University of Leicester (UK) and a Master's degree in Science Communication from Imperial College London (UK).
Michael Rast studied geology and geoscientific remote sensing at Ludwig-Maximilians University in Munich. He later joined ESA, where he helped define mission and science requirements for Earth observation satellites. After spending a research year at NASA's Jet Propulsion Laboratory, he earned a doctorate in imaging spectroscopy from space. Following a secondment to the GEO Secretariat in Geneva as a Senior Programme Officer, he led the Science Strategy Office at ESA-ESRIN in Frascati, Italy. In 2017, he became Senior Advisor to the Director of Earth Observation Programmes. Since retiring from ESA in 2022, he has served as Director of Earth Sciences at the International Space Science Institute (ISSI) in Bern, Switzerland. Michael Rast is also a Professor of Terrestrial Remote Sensing in the Department of Geography at Ludwig-Maximilians University.
Narelle van der Wel is a Science and Communications Officer at the World Climate Research Programme (WCRP) Secretariat, hosted by the World Meteorological Organization (WMO) in Geneva. She works across several areas including strategic planning and implementation, science coordination, and communication and outreach. Narelle earned a Ph.D. in Polar Studies (Glaciology) from the Scott Polar Research Institute, University of Cambridge (UK), where she focused on the numerical modeling of Antarctic ice streams. She later worked as a Postdoctoral Research Assistant at the same institute, modeling glacier flow in Greenland. In 2018, she completed a Postgraduate Certificate in Climate Change Management at the University of Edinburgh.
Hannah Liddy is the Executive Director of the Analysis, Integration, and Modeling of the Earth System (AIMES), a global research network of Future Earth, hosted at the Center for Climate Systems Research at Columbia University and the NASA Goddard Institute for Space Studies. Through AIMES, She leads interdisciplinary initiatives that integrate climate, ecosystem, and social systems research. Her work has contributed to syntheses of past abrupt climate change events, climate tipping points, and cascading impacts in the Earth system. She has also helped design model intercomparison experiments assessing the risks of crossing critical Earth system thresholds, using both coupled Earth system models and domain-specific tools. Her current research explores tipping dynamics under zero-emissions scenarios and their associated risks. She holds a Ph.D. in Geological Sciences from the University of Southern California and has published widely on carbon cycling, tipping points, and Earth system interactions.
Richard Wood leads the Climate, Cryosphere and Oceans group in the Met Office Hadley Centre. He was a founder member of the Met Office Hadley Centre in 1990. He trained as an applied mathematician, and was a member of the original teams that developed the ocean component of the Unified Model, and later the Met Office climate models Met Office climate prediction model: HadCM2 and Met Office climate prediction model: HadCM3.