Fossil fuel emissions are projected to edge down in 2026, but that would not be enough to bring global carbon dioxide emissions lower overall. A report on the latest Global Carbon Budget estimates that emissions from fossil fuels will fall by 0.4%, while total CO₂ emissions, including land-use change such as deforestation, rise to 43.3 billion metric tons from 42.8 billion in 2025.
The figures are projections in the 2026 budget, an annual assessment compiled by an international collaboration of more than 140 scientists. A ScienceDaily report based on materials from the University of Exeter says the budget is scheduled to appear as a preprint in Earth System Science Data, with a peer-reviewed version to follow. The research was led by Pierre Friedlingstein, who directs the Global Carbon Budget Office at the University of Exeter.
The expected fossil-fuel decline reflects both a growing contribution from clean energy and temporary changes in energy use. Solar power, wind power and electric vehicles are meeting roughly two-thirds of the increase in global energy demand, the report says. But disruptions associated with the Iran conflict are also expected to affect emissions, including a projected 1.9% drop in oil-related CO₂. The report’s estimates put fossil-fuel emissions at 38.2 billion metric tons in 2026.
Friedlingstein cautioned against reading a single-year decline as a durable shift: “A decline in fossil CO₂ emissions is encouraging, but a reduction driven partly by geopolitical shocks is not a sustainable climate solution.” For a lasting fall, the report argues, clean energy technologies need to expand faster and replace fossil-fuel use over time.
Land-use emissions are a major reason the total is expected to rise despite the projected fossil-fuel dip. They are forecast to reach 5.1 billion metric tons of CO₂ in 2026. The report links the increase to peat fires, described as almost entirely ignited by human activities, and forest degradation in Southeast Asia; drier conditions associated with a developing El Niño have contributed to these problems. The estimate shows how forest loss and other land changes can counter some gains from cleaner energy.
The budget puts the remaining carbon allowance for limiting warming to 1.5°C at about 150 billion metric tons of CO₂, which the researchers estimate could be used up in less than four years at current emission rates. This is a rate-based estimate, not a fixed date: how quickly the allowance is consumed depends on future emissions. The report also projects atmospheric CO₂ concentrations of 427.7 parts per million in 2026, about 54% above pre-industrial levels.
Natural carbon sinks absorb some of the CO₂ released by human activity. The report says land ecosystems’ carbon uptake has recovered to earlier levels after weakening during the 2023–24 El Niño, while the powerful 2026 El Niño is expected to influence absorption in the coming year. Reforestation and new forests remove substantial carbon, but the report estimates those gains offset only about half the emissions from permanent deforestation. Newer carbon-removal technologies, excluding conventional approaches such as reforestation, remain very small in scale.
The report also describes uneven changes among major economies. China’s fossil-fuel emissions are projected to fall 0.9%, while India’s are expected to rise 4.4%; the United States, European Union and Japan are also projected to record declines. These country estimates and the global total are forecasts for 2026, so they do not establish that emissions have reached a lasting peak.
A separate analysis by the same researchers, described as in press in another peer-reviewed journal, estimates that clean technologies could offset 64% to 79% of emissions that would otherwise result from growing energy demand through the end of 2028. It also finds that 59 countries had lower emissions in 2025 than in 2019 while their economies grew. Those findings point to progress, but the budget’s central warning is that current gains have not yet secured a sustained global decline.