Positive and negative tipping points

In the final episode of the year, Anna speaks to Professor Tim Lenton (Chair in Climate Change and Earth System Science at the University of Exeter) about climate tipping points – the thresholds where a tiny change could lead to large and often irreversible transformations in the Earth system, with potentially disastrous consequences. Examples of such 'negative' tipping points include the dieback of the Amazon rainforest, the melting of the Greenland icesheet, and the collapse of the Atlantic Meridional Overturning Circulation (AMOC). But not all tipping points are bad. In the interview, Anna and Tim also discuss how the triggering of 'positive tipping points' within human societies could lead to rapid decarbonization.   For further reading, please see: Tim Lenton's book 'Positive Tipping Points: How to Fix the Climate Crisis'. Tim Lenton's article 'Why some tipping points may be positive for the planet' in Chatham House's magazine 'The World Today'.

COP30 in Belém is over. What happened at the conference? What were the main outcomes? And what needs to happen next?   To find out, Anna speaks to Jennifer Morgan (Senior Fellow at the Fletcher School of Law and Diplomacy at Tufts University; Fellow at the Hertie School of Governance; and former State Secretary and Special Envoy for International Climate Action at the German Federal Foreign Office) and David Waskow (Director for the International Climate Initiative at the World Resources Institute).

COP30 is about to begin. Where do we stand ahead of the conference? What are the key issues to watch, and how might the complex geopolitical context influence the discussions in Belém? To find out, Anna is joined by three Chatham House colleagues: Ana Yang (Director of the Environment and Society Centre), Bernice Lee (Distinguished Fellow and Senior Advisor) and Nick Bridge (Associate Fellow at Chatham House and former UK Special Representative for Climate change).  For additional analysis, please see: The expert comment 'What can COP30 achieve, following US withdrawal and underwhelming climate plans', available here. The explainer 'What is COP30 and why does it matter for the climate?, available here. The expert comment 'The UN climate process remains indispensable', available here.

The incoming COP30 host, Brazil, has signalled it wants COP30 to mark the moment the UNFCCC transitions to a 'post-negotiation' phase, and that efforts should focus on action and implementation going forward. As part of its work to make this a reality, Brazil is reforming the UNFCCC's 'Action Agenda', a process bringing together cities, regions, businesses, investors, civil society and governments to implement the Paris Agreement.  To find out more about Brazil's vision for the Action Agenda, co-hosts Anna and Bhargabi speak to Dan Ioschpe, Brazil's Climate High-Level Champion for COP30.  In the introduction to the episode, Anna and her colleague Chris Aylett (Research Fellow at Chatham House) discuss the EU's commitment to phase out Russian energy imports by 2028 and US efforts to block a plan for decarbonizing international shipping. 

The multilateral development banks (MDBs) play a critical role in addressing climate change and have a key role to play in delivering on the 'New Collective Quantified Goal' on climate finance, agreed at COP29. This Climate Briefing episode focuses on the newest of the MDBs: the Asian Infrastructure Investment Bank (AIIB), launched in 2016. What are the similarities and differences between the AIIB and the other MDBs? What is the AIIB doing to address climate change?  To find out, Anna and Bhargabi speak to Kim-See Lim (Chief Investment Officer, Public Sector (Region 1) & Financial Institutions and Funds (Global) Clients at the AIIB) and Hans Peter Lankes (Managing Director and Deputy Chief Executive at the Overseas Development Institute; Visiting Professor in Practice at the LSE Grantham Research Institute; and a Senior Fellow at the LSE/Oxford International Growth Centre).  In the introduction to the episode, Anna and Bhargabi speak about growth trends in global renewable energy generation, climate politics in the UK, the US-China trade spat and the ratification of the High Seas Treaty.

Forests play a critical role in the fight against climate change. With COP30 taking place in the Amazon, addressing deforestation is likely to be a topic of high priority at the meeting. But what can actually be achieved? To find out, Anna and Bhargabi speak to Mauricio Voivodic, Executive Director of WWF-Brazil, and Edward Davey, Head of the UK Office of the World Resources Institute. In their introduction to the episode, Anna and Bhargabi speak about key developments at the opening of the 80th Session of the UN General Assembly (UNGA) and New York Climate Week.  

Trump 2.0 poses a huge challenge for the renewable energy industry in the US. Not only has the administration rescinded environmental incentives and regulations with bearing on future projects, it has also in various ways delayed and/or obstructed offshore wind projects already under construction (like the Empire Wind and the Revolution Wind projects). What does all of this mean for the renewable energy industry in the US? What does it mean for US competitiveness and the global energy transition? In the introduction, Anna is also joined by Chris Aylett, a Research Fellow at Chatham House's Environment and Society Centre, to discuss some of the main climate stories in the run-up to COP30. To find out, Bhargabi speaks to Ben Backwell, CEO of the Global Wind Energy Council, a member-based organisation that represents over 1,500 companies, organisations and institutions in over 80 countries.

In this third instalment of the Future of Climate Diplomacy mini-series, Climate Briefing hosts Anna and Bhargabi explore what lessons that can be drawn from the history of the climate negotiations and how this can inform the future of climate diplomacy. To do this, they are joined by long-time COP researcher Dr Joanna Depledge (Research Fellow at the Centre for Environment, Energy and Natural Resource Governance and at Centre for Science and Policy, both at the University of Cambridge).   This week's Climate Briefing also includes a chat with Dr Patrick Schröder (Senior Research Fellow at Chatham House's Environment and Society Centre), who explains why the negotiations on a global plastics treaty are important and why the recent round of talks, once again, ended with no deal.   To find out more about the plastics treaty negotiations, see this piece in Foreign Policy by Patrick Schröder.   And to find out more about the proposal to introduce a voting rule at COP, see this piece by Dr Joanna Depledge.

On the 23rd of July 2025, the International Court of Justice (ICJ) issued its long-awaited Advisory Opinion on the obligations of states in respect to climate change. The Advisory Opinion makes clear that states have far-reaching obligations under international law to prevent harm to the climate system and that breaching such obligations could result in having to make reparations, among other things.   So, what impact might the ICJ's ruling have on international climate diplomacy and action, including climate-related litigation? To find out, Anna and Bhargabi speak to Dr Margaretha Wiwerinke-Singh, who is an Associate Professor of Sustainability Law at the University of Amsterdam and who lead the legal team of Vanuatu and the Melanesian Spearhead Group throughout the ICJ proceedings, and Dr Maria Antonia Tigre, who is the Director of Global Climate Change Litigation at the Sabin Centre at Columbia University.   To learn more about the ICJ's Advisory Opinion, read this Chatham House expert comment and/or listen to this Climate Briefing interview with Ralph Regenvanu, who at the time of the interview served as Vanuatu's Minister of Climate Change Adaptation, Meteorology and Geo-Hazards, Energy, Environment and Disaster Risk Management.

Ahead of the landmark COP30 in Belem, Brazil, this November, calls for reform of the UNFCCC and COPs are growing, as are concerns that the only formal global forum for climate negotiation and cooperation is under threat. In a series of conversations, Anna, Ruth and Bhargabi interview thought leaders in the climate world about what the future of climate diplomacy should look like. The second guest in this mini-series is Kaveh Guilanpour, Vice President for International Strategies at C2ES, former lead of the UK's UNFCCC negotiations, co-lead negotiator for the EU, co-lead negotiator for the Alliance of Small Island States, and head of secretariat for the High Ambition Coalition, and senior advisor to the UNDG's Climate Action Team.