What are the most important changes the Paris Agreement has brought about? How should the COP process evolve? And why does geoengineering need to be approached with caution?

The fourth part of the Future of Climate Diplomacy mini-series features a fascinating conversation between Chatham House's Chris Aylett (standing in for Anna and Bhargabi) and Laurence Tubiana, CEO of the European Climate Foundation and previously France's Climate Change Ambassador and Special Representative for COP21.

The race to secure critical raw materials is turning attention towards an unlikely place: the ocean floor. In this episode, Anna speaks with Dr Isaac Kardon (Senior Fellow at the Carnegie Endowment for International Peace) and Meredith Schwartz (Associate Fellow at the Centre for Strategic and International Studies) about the geopolitics of deep-sea mining.

The EU has introduced a Carbon Border Adjustment Mechanism (CBAM) to prevent carbon leakage – when companies move production to countries with weaker climate rules, or when EU products are replaced by more carbon-intensive imports. But the measure has sparked controversy and concern, especially among countries in the Global South, as seen during COP30 in Belém.

This episode of the Climate Briefing explores the implications of the EU's CBAM for countries in the Global South: What are their main concerns, and what could be done to mitigate negative impacts?

To discuss these questions and more, Anna is joined by Aparna Sharma (Programme Lead at the Council on Energy, Environment and Water – CEEW), Shimukunku Manchishi (Senior Policy Officer at the African Futures Policy Hub), and Ieva Baršauskaitė (Lead on Trade and Green Transition at the International Institute for Sustainable Development – IISD).

Exactly one year has passed since President Trump returned to the White House. How has the first year of Trump 2.0 impacted global efforts to address climate change, and what might happen going forward?

To discuss this, Anna and Bhargabi are joined by Gina McCarthy (former US National Climate Advisor, former EPA Administrator and Chair of the America Is All In Coalition).

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.