The Global Tipping Points Conference 2025, held at the University of Exeter, brought together researchers, policymakers, and businesses from around the world to raise awareness and strengthen understanding of global climate tipping points.

With a programme featuring over 30 keynotes, 50 workshops and research sessions, and a series of networking activities, the conference aimed not only to communicate the latest scientific insights, but also to identify pathways for accelerated global climate action.

A comprehensive rundown of the conference is available via Carbon Brief here: https://www.carbonbrief.org/tipping-points-window-to-avoid-irreversible-climate-impacts-is-rapidly-closing/

TipESM_core experiment protocol

Among the scientific contributions presented during the week was the TipESM_core protocol, developed as part of the TipESM project. The protocol offers a structured experimental framework for simulating tipping elements across Earth system models. It was designed in close dialogue with the international ESM community over the first year of the project, including through a series of dedicated online workshops.

A key outcome from the conference was the recognition that the TipESM_core protocol has now been fully accepted internationally and is being implemented globally as the TIPMIP ESM experiment.

Colin Jones, who is leading the work in Work Package 1 on ESM protocols, simulations, and data in TipESM spoke about the efforts behind the protocol.

“The TipESM_core experiment protocol was initially conceived as part of the proposal for TipESM. Once the project started, we rapidly tested the protocol and proposed it as a potential ESM protocol for the international TIPMIP project. We organized 3 online workshops to develop a protocol that would be accepted by most international ESM groups. This led to 13 ESMs around the world now running the protocol (9 have largely completed all simulations). We agreed with the TIPMIP organizers that the resulting data will be openly-available through publication on the Earth System Grid Federation (ESGF) at DKRZ in Germany. We hope much of this data will be available by the end of 2025. TIPMIP ESM has been accepted as a community science MIP in CMIP7 and a paper on the experiment protocol and first results will be submitted to Geoscientific Model Development (GMD) in July 2025. After that we plan to organize at the international level, scientific analysis of the TIPMIP ESM multi-model ensemble. This will have TipESM scientists at the core. These developments would not have been possible without the support from TipESM.”

The protocol and its initial results were featured during the Modelling Tipping Points session and in a workshop on “Updates and Next Steps within Tipping Points Modelling Intercomparison Project” led Donovan Dennis, Ricarda Winkelmann, and Sina Loriani from the Potsdam Institute for Climate Impact Research.

Among the presentions on the protocol, Jeremy Walton of the UK Met Office Hadley Centre presented an analysis comparing the performance of the TipESM_core protocol against CMIP6 historical simulations and observational data. The findings showed that, despite its simplicity, TipESM_core simulations yielded results that are as realistic as those from more complex, realistically forced experiments such as CMIP6.

In another contribuColin Jones, who is leading the work on ESM protocols, simulations, and data, presented results from UKESM1.2 simulations following TipESM_core. Two tipping events were showcased seen in the runs. These included:

• A collapse of the North Atlantic subpolar gyre, which can recover if negative CO2 emission runs are applied after the positive CO2 emissions and
• A collapse of the Ross Ice Shelf in Antarctica, with a determination that it is at risk of rapid collapse in the global warming range 3.4 C to 4.2 C, but can partially (though very slowly) recover when negative CO2 emissions are applied in the model

TipESM Representation at the Conference

Beyond the protocol, TipESM researchers played a prominent role across the conference programme:

• Friederike Fröb on loss of habitability for deep sea and sea floor organisms – such as cold-water corals – in selected overshoot scenarios
• Desislava Petrova contributed to the Tipping Points in the Biosphere session with a presentation on the ENSO-driven climatic and vegetation changes in Amazonia by the end of the century.
• Andy Hartley presented in the session “Assessing Systemic and Cascading Risks of the Earth System Tipping Points for People”. His talk, “Societal and ecosystem risks associated with climate tipping points”, introduced the TipESM Risk Register. Andy was also interviewed for Carbon Brief’s roundup from experts on which tipping points he finds most concerning (read it here)
• Ivana Cvijanovic presented a talk entitled, “Towards legal recognition of loss of habitability due to extreme heat” in the session, “Earth System Tipping Risks: Testing the Limits of International Environmental Law”

The strong engagement of TipESM partners throughout the programme further reinforced the project’s growing visibility and relevance within the global tipping points research community.