Originally published November 7, 2016. Updated July 28, 2026.
COP30, the UN’s climate summit in Belém, Brazil, ran from November 10 to 21, 2025, and it closed without a binding promise to phase out fossil fuels. That gap between ambition and the final text is the pattern across the summits that came before it. The pledges countries have filed, if every one gets kept, point to about 2.3 to 2.5 degrees Celsius of warming by 2100, according to the UN Environment Programme. Look at current policies instead of pledges, and that number rises to 2.8 degrees. Both figures still miss the Paris Agreement’s target of holding warming well below 2 degrees Celsius.
Copenhagen’s collapse and Cancún’s rescue
The UN’s climate summits started out fragile. At COP15 in Copenhagen in 2009, negotiators produced the Copenhagen Accord, but the conference never adopted it by full consensus, and some countries opposed it. The Accord still moved money: rich countries pledged $30 billion in “fast-start” finance for 2010 through 2012, and set a target of mobilizing $100 billion a year by 2020.
Cancún, a year later, is where the process caught itself. COP16 formally adopted the 2 degree limit that Copenhagen had only gestured at, and created the Green Climate Fund, run by a 24-member board with the World Bank as its interim trustee. Negotiators also agreed shared rules for measuring and verifying emissions cuts, plus the REDD+ framework.
Durban opens the door, Paris and Marrakech walk through it
COP17 in Durban in 2011 is where the current structure got its start. Negotiators launched what they called the Durban Platform, a mandate to negotiate a new agreement with legal force that would apply to every country, with talks to start in 2012 and wrap up no later than 2015, the resulting agreement due to take effect from 2020.
They hit that deadline. The Paris Agreement was adopted at COP21 on December 12, 2015, by 195 parties, and it set the current target, keeping warming well below 2 degrees Celsius while pursuing efforts toward 1.5 degrees. It took legal effect on November 4, 2016.
COP22 in Marrakech convened days after the Paris Agreement took legal effect.
Glasgow names coal, Dubai names fossil fuels
COP26 in Glasgow, held October 31 to November 12, 2021, is where the Paris Agreement’s operating manual got finished. Negotiators agreed the Article 6 rules for international carbon markets after six years of deadlock, and finalized the Enhanced Transparency Framework that countries use to report their emissions. Glasgow’s decision text also became the first at a COP to mention coal and fossil fuel subsidies by name, calling for cutting back on coal power that lacks emissions controls and moving off subsidies that prop up fossil fuels.
COP28 in Dubai, two years later, went further. The summit, which drew roughly 85,000 attendees between November 30 and December 13, 2023, completed the first Global Stocktake, the UN’s formal check on progress against the Paris targets, and found that progress was “too slow across all areas.” For the first time, the decision text called on every country to start “transitioning away from fossil fuels in energy systems… in a just, orderly and equitable manner.”
Baku’s finance number and Belém’s stalled roadmap
COP29 in Baku set a new finance number. Developed countries agreed to lead the effort to mobilize $300 billion a year by 2035 for developing nations, up from the old $100 billion goal. The summit also called for $1.3 trillion a year from all sources by the same date.
COP30 in Belém ran from November 10 to 21, 2025. The final decision text left out binding language on phasing out fossil fuels after oil-producing states objected, and Brazil’s presidency pushed that fight outside the formal negotiating track, launching voluntary roadmaps on fossil fuels and deforestation for countries to take up at a summit in Colombia in April 2026, according to Wikipedia’s account of the conference. The outcome text did call for tripling adaptation finance by 2035, though Wikipedia’s summary notes the funding sources for that goal were left unclear, and it repeated the $1.3 trillion goal set at Baku.
What the pledges add up to for warming
How much warming the current round of pledges adds up to depends on which tracker you check, because the two main ones use different methods and shouldn’t get blended into one number. The UN Environment Programme’s Emissions Gap Report, published November 4, 2025, put full implementation of current pledges at 2.3 to 2.5 degrees Celsius by 2100, and current policies alone at 2.8 degrees, noting that this year’s new pledges “barely moved the needle” from the year before. Climate Action Tracker, updated November 13, 2025, put current policies at roughly 2.6 degrees. Pledges and targets bring that median down to roughly 2.2 degrees, and every net-zero promise on the books, if kept, brings it to roughly 1.9 degrees.
Both trackers point the same direction even after the different math. None of these numbers gets warming under the Paris Agreement’s 1.5 degree target, and current policy alone doesn’t hold the line at 2 degrees either.
The US steps back from Paris
On January 20, 2025, the White House signed an executive order directing the US ambassador to the UN to file a withdrawal notice from the Paris Agreement “immediately”. The agreement doesn’t work that fast. Article 28 requires a full year’s notice before a withdrawal takes legal effect, and the UNFCCC’s own count of member parties dropped from 195 to 194 as of January 27, 2026, about a year after the notice went in.
That leaves 194 parties still working from a new round of national pledges. The current round, called NDC 3.0, was shaped by the first Global Stocktake’s findings from COP28, and every pledge countries file goes into the UNFCCC’s public registry for anyone to check.
What would move the number next
The clearest test ahead is the summit in Colombia in April 2026, where countries are supposed to bring the voluntary fossil-fuel and deforestation roadmaps that Belém’s decision text couldn’t include, according to Wikipedia’s account of that outcome. If those roadmaps come out of Colombia with enforcement behind them, that’s the fossil-fuel commitment Belém’s own decision text couldn’t produce.
The next pledge cycle is also worth watching. Countries file pledges on a five-year cycle, and the next full update to the UNFCCC’s registry comes due in 2030, years before the century-end targets these reports project against.
The other number worth tracking is the gap between the UN Environment Programme’s 2.8 degree current-policy figure and its 2.3 to 2.5 degree pledge figure. That gap, promises against actual policy, is still open, and this year’s round of pledges barely moved it.
