It was supposed to be the year the world course-corrected. Instead, ten years after the Paris Agreement was adopted, a flagship UN assessment warns that governments have “missed the mark” for the third time in a row – and are now gambling with a far hotter, more dangerous planet.

The United Nations Environment Programme’s new Emissions Gap Report 2025: Off target shows that global greenhouse gas pollution is still rising when it should be plummeting. In 2024, total emissions climbed to an all-time high of 57.7 billion tonnes of CO2-equivalent, a jump of 2.3 per cent in a single year. That growth rate is more than four times higher than the yearly average in the 2010s and eerily similar to the fossil-fuel boom years of the 2000s. According to the report, this relentless increase is now locking in levels of warming that will push the planet beyond 1.5°C very soon – and potentially keep it there for decades unless action changes dramatically.

Behind that headline number lies a grim mix of old habits and new warning signs. CO2 from fossil fuels still accounts for roughly 70 per cent of global emissions, driven by coal, oil and gas use in power plants, cars, industry and buildings, plus cement and metal production. But 2024 also brought a sharp spike in emissions from forests and land-use change. Net CO2 from deforestation and other land-use activities rose by around one-fifth compared with 2023, and this alone explains more than half of the global emissions increase. The report links this jump to continued forest clearing and extreme fire seasons in parts of South America under hot, dry El Niño conditions, which helped turn vast landscapes into temporary carbon firestorms.

Those fires and forest losses are not just a line in a balance sheet. When primary forests are cleared or burned, they take centuries to fully recover – if they recover at all. Communities downwind face choking air pollution, black carbon darkens ice and accelerates melting, and already-threatened species lose the last fragments of their habitat. The report cites new analysis showing that global primary forest loss in 2024 surged compared with the previous year, with total tree cover loss hitting record levels, undercutting both climate goals and biodiversity promises. In other words: nature, our biggest ally in storing carbon, is being pushed into reverse.

Responsibility for this rising tide of emissions remains deeply uneven. Members of the G20 account for roughly 77 per cent of global greenhouse gas output. Among the six biggest emitters – China, the United States, India, the European Union, the Russian Federation and Indonesia – only the EU managed to reduce emissions in 2024. India and Indonesia posted some of the fastest growth, reflecting their rapid development and energy demand. Yet least developed countries together still produce only about 3 per cent of global emissions, despite being most exposed to heatwaves, drought, floods and sea-level rise. Per person, emissions in wealthy economies remain several times higher than in many low-income and emerging economies, even as the latter struggle to expand energy access and basic infrastructure.

Against this backdrop, 2025 was meant to be the moment when countries ratcheted up their climate promises. Under the Paris Agreement’s five-year ambition cycle, all parties were asked to submit new or updated “nationally determined contributions” (NDCs) this year, including fresh 2035 targets. Instead, by 30 September only around a third of countries had actually delivered new NDCs, covering just 63 per cent of global emissions, according to the Emissions Gap Report 2025. Even more worrying: only a handful used the opportunity to strengthen their 2030 targets, the commitments that matter most for immediate action.

The new pledges that have appeared do nudge global projections – but only slightly. If every country fully implemented both its unconditional and conditional NDCs, including the new 2035 targets, the report estimates that end-of-century warming could be held to about 2.3–2.5°C, down a few tenths of a degree from last year’s assessment. Part of that improvement is technical, due to updated climate modelling methods. Another slice is due to stronger policies in some major economies, notably China’s faster-than-expected rollout of renewable power. But the report warns that the imminent withdrawal of the United States from the Paris Agreement will effectively erase about 0.1°C of that hard-won progress, because the country’s new 2035 pledge will no longer count and recent rollbacks in US climate policy push its real-world emissions higher again.

Crucially, the world is not even on track to meet these still-insufficient NDCs. Under policies already in place, the report projects that global emissions in 2030 will be around 58 GtCO2e. That’s roughly 5 GtCO2e higher than where they would be if current unconditional NDCs were fully delivered, and about 7 GtCO2e above the level implied by unconditional plus conditional pledges. The gap gets even wider by 2035. Seven G20 members are likely to hit their 2030 targets with existing policies, but nine are not. Some countries, like Brazil and South Africa, have narrowed the gap and could meet their targets with modest extra effort; others, including the United States, Canada and Saudi Arabia, are far off course.

The real shock in the numbers comes when UNEP compares today’s promises with what science says is needed to honour the Paris temperature goal. To have a decent chance of staying “well below” 2°C, global emissions in 2030 would need to be around 25 per cent lower than they were in 2019. For a 1.5°C-aligned pathway, they would need to fall by about 40 per cent by 2030 and 55 per cent by 2035. Instead, on the current trajectory – even if all unconditional pledges are met – emissions in 2035 are set to be only about 12–15 per cent below 2019 levels. For 2°C, that leaves a gap of about 12 GtCO2e in 2030 and again in 2035; for 1.5°C, the gap is around 20 GtCO2e in 2030 and 23 GtCO2e in 2035, according to the Emissions Gap Report 2025. These are not small tweaks; they are entire coal, oil and gas systems that have yet to be turned around.

Translated into temperatures, the story is even more unsettling. If the world simply continues with policies already on the books, the report finds that warming is on track to reach up to 2.8°C this century, with a two-in-three chance of crossing at least 2.1°C. Implementing all current NDCs would lower that to about 2.3–2.5°C. Even in the most optimistic pledge scenario – where every conditional promise is fulfilled and every net-zero target is actually met – global temperature rise is still likely to peak close to 1.9°C. In that best case, there is only about a one-in-five chance of keeping warming at or below 1.5°C over the century.

The report’s authors stress that overshooting 1.5°C is no longer a remote possibility but the central expectation. At today’s rate of emissions, the remaining carbon budget for a 50 per cent chance of staying below 1.5°C without overshoot will be exhausted before 2030. New “rapid mitigation” pathways that start from the reality of continued high emissions show that returning to 1.5°C by 2100 is still technically possible, but only by accepting a temporary overshoot of around 0.2–0.3°C. Every tenth of a degree above 1.5°C substantially increases the risk of triggering climate tipping points – such as irreversible ice-sheet loss in West Antarctica or the die-back of parts of the Amazon – and multiplies the damages, from deadly heatwaves to crop failures and coastal flooding.

Those higher-overshoot pathways also rely heavily on large-scale carbon dioxide removal later in the century, through technologies like direct air capture or bioenergy with carbon capture and storage, or through massive expansions of forests and other ecosystems. The Emissions Gap Report 2025 warns that to lower global temperature by just 0.1°C after an overshoot would require removing and permanently storing around five years’ worth of today’s global CO2 emissions. That is an enormous technical and political gamble, given the current tiny scale of removal projects and the land, water and biodiversity pressures that large deployments would create.

Yet the report is not nihilistic. It stresses that the last decade has also brought genuine progress, much of it catalysed by the Paris Agreement itself. Projected warming from current policies has fallen from almost 4°C in 2015 to under 3°C today. Around 70 per cent of global emissions are now covered by net-zero pledges. Governance frameworks and climate laws have multiplied. Renewable energy costs have plunged, and the global roll-out of wind, solar and electric vehicles has repeatedly beaten expert forecasts. Methane, a powerful short-lived greenhouse gas, is finally getting serious attention through initiatives such as the Global Methane Pledge, even if current plans still fall short of the pledge’s 30 per cent reduction goal by 2030.

The problem is speed and scale. Inger Andersen, UNEP’s Executive Director, argues in her foreword to the Emissions Gap Report 2025 that climate action “is not philanthropy – it is national self-interest”, pointing to the economic growth, jobs, health benefits and energy security that come with a fast clean-energy transition. The report calls in particular on G20 governments to ditch new fossil infrastructure, rapidly expand renewables and energy efficiency, phase out fossil fuel subsidies, halt deforestation, and massively increase financial support for poorer nations. Without a surge in affordable finance and technology transfer, many developing countries simply cannot leapfrog to low-carbon systems at the pace the science demands.

The message as the world heads toward COP 30 in Belém, Brazil, could hardly be more urgent. The next few years are not just another round in slow-motion diplomacy; they are likely to decide how far the planet overshoots 1.5°C, how many tipping points are triggered, and how much suffering is locked in for the most vulnerable communities. The 2025 Emissions Gap Report is a warning flare: the world is still off target, the carbon clock is still ticking up, and the window to make the overshoot small and temporary is closing fast. Whether governments seize this moment or let it slip will define the climate story of the rest of the century.