Belém set the tone: little left to negotiate

When the 2025 climate summit opened in the Amazonian port of Belém, the Brazilian hosts had already removed the issue most delegates assumed would sit at its heart: the national emissions-cutting plans that form the bedrock of the Paris agreement. Brazil insisted those plans were the business of national governments alone and not up for negotiation at the talks.

Negotiators saw the consequence immediately.

• •A seasoned global south negotiator, speaking before the summit, said: "In that case, it will be a very short Cop ... There is nothing to negotiate."
• •Another developing country diplomat said: "They have decided that there is no appetite for negotiation, with the US out of Paris," adding that "countries won't engage."

The summit did end with a deal, although few loved it, and the faultlines opened by Brazil's decision are deepening going into the 2026 summit.

What the consensus process has cost

The strain on the climate talks ten years in is not only about one host's choice of agenda. The machinery built around the Paris agreement has been slow from the start: it took more than five years just to negotiate the Paris "rulebook" that interprets and implements the treaty.

Other structural features have compounded the slowness:

• •Every resolution requires consensus, a rule that has let Donald Trump's allies - in Saudi Arabia, Russia, Venezuela and some other petrostates - frequently veto measures.
• •More than 30 years passed between the signing of the UN framework convention on climate change in 1992 and the first direct treatment of fossil fuels, at Cop28 in Dubai in 2023. There, countries agreed for the first time to "transition away from fossil fuels", but set no timeframe or supporting policies.
• •The US, responsible for about one in every eight tonnes of carbon dioxide emitted today, has withdrawn from Paris under President Trump.

Paul Bledsoe, a former Clinton White House climate adviser now at American University, put the frustration bluntly: "The structures of Cops and Paris are labyrinthine, bureaucratic, and ultimately dispiriting." He added that it may be time to streamline them to focus more deliberately on national emissions reduction goals.

The numbers behind the disappointment

Governments pledged under Paris to limit global heating to 1.5C above preindustrial levels, yet temperatures for two years have exceeded that threshold. The rate of warming itself has doubled: temperatures were rising at 0.2C a decade in 2015, and today the rate is 0.4C a decade and still accelerating. The UN recently said its most optimistic estimate was now for about 1.7 to 1.8C of heating.

Johan Rockström, director of the Potsdam Institute for Climate Impact Research, said the world will inevitably breach the 1.5C limit within three to five years, that tipping points are coming closer fast, and that the current path - a global path he said will take us to a catastrophic 2.6C-3C of warming within the Paris framework - "cannot be considered as anything but a global failure".

Major emitters' records underline the gap between pledge and practice:

• •Australia, co-host of Cop31, has set no end to its fossil fuel exports, while fellow co-host Turkey plans to increase its carbon output.
• •The UK is opening a gasfield and considering a new oilfield; Germany has dropped its electric vehicle sales targets and scrapped a renewable heating law.
• •Most rich countries are reducing their contributions to climate finance for the poor.

Juan Carlos Monterrey, former climate envoy for Panama and now chief executive of the Vanglabs consultancy, judged the decade harshly: "A lot of the commitments, the promises that were made, just turned out to be a bunch of hot air." Measured against the treaty's aims, he said, "Under that measure, we have failed."

Defenders of the treaty, and what could fix the talks

That was Rockström's verdict, offered alongside his argument that the global climate crisis can, in the end, only be solved if every country moves away from planet-damaging heat injection at the same time. Monterrey agreed on the direction if not the pace: "Paris is our moral compass. It has told us where we should go. The speed of travel is not what it needs to be, but Paris has set the direction."

Defenders point to change happening well outside the negotiating rooms:

• •In Pakistan, rooftop solar panels have taken off and now make up about a quarter of electricity use in the country.
• •In Vietnam, cheap electric vehicles from China make up more than 40% of car sales.
• •Claudio Angelo of the Observatório do Clima thinktank said: "The solar panels on my roof and the BYD Dolphin [electric car] my neighbour drives are exhibit one and exhibit two of Paris's success." He added that Paris will not prevent 1.5C overshoot and is unlikely to prevent 2C, but "the transformation it has triggered can't be exaggerated".
• •Li Shuo, director of the China climate hub at the Asia Society Policy Institute, said China takes multilateral climate efforts more seriously than it did a few years ago because its economic stakes have grown enormously - asking: "If the world abandons decarbonisation, where will China sell its solar panels and electric vehicles?"

Reform is also gathering outside the formal process. Cop30 ended without a strong statement on phasing out fossil fuels; in response, nearly 60 countries gathered in Colombia in April and committed to drawing up their own national roadmaps for moving away from fossil fuels, and France, Germany and the Netherlands have so far produced such plans.

Bledsoe wants more side agreements on the "super pollutants" - methane, HFC refrigerants, ground-level ozone, nitrous oxide and black carbon - arguing that cutting methane by 40% alone could hold down temperatures by about 0.3C in the next decade, with deeper cuts yielding a 0.5C decrease by 2100. "Paris was never intended to do all the hard work itself," he said. "We need to use the G7, the G20 and other forums too."

Electrification is the quieter engine behind the shift: Jan Rosenow, professor of energy and climate policy at Oxford University, estimates that because electricity is so much more efficient, the world's total final energy use can be halved by switching to electric for everything.

The next test comes at the 2026 summit, the first Cop with a split presidency and host: it will be held in Turkey but presided over by Australia.