Five key issues at the UN climate summit in Brazil – and why they matter to you and the planet

The world’s most important climate summit – known this year as Cop30 – has begun in the Amazonian port city of Belém, Brazil. It promises to be contentious: key countries haven’t submitted new climate plans, and negotiations are held up by disputes over who should pay for climate action.

We attended a preliminary round of negotiations in June, which ended with very few concrete agreements. Many outcome documents were instead heavily caveated as “not agreed”, “open to revision”, or “without formal status”.

Those fractious pre-summit talks followed a disappointing Cop29 in Azerbaijan last year. This year, here are five key issues to watch – and why they matter.

Are countries keeping their Paris pledges?

Ten years after the Paris agreement, countries are due to submit their third round of national climate plans, or nationally determined contributions (NDCs) in the jargon. These are refreshed every five years and are supposed to present “best efforts” to scale up climate action.

Yet as of November 2025, only 79 countries – covering 64% of global emissions – have submitted their NDCs. Countries not submitting include some of the highest emitters, such as India, while the US has (once again) left the Paris agreement and will not have high-level representatives at Cop30.