• Analysis
Fossil fuel emissions drop of 0.4% in 2026 may not last, researchers warn
Global fossil fuel emissions are projected to fall 0.4% in 2026, the first decline since the Covid pandemic, but researchers warned Tuesday the drop may be short-lived because it is driven partly by an oil price shock linked to the Iran war.
Why the 2026 decline may not hold
The projected fall in fossil fuel emissions - 0.4% in 2026, the first since Covid paralysed the global economy, trade and transport in 2020 - carries a warning from the scientists behind the Global Carbon Budget report. Corinne Le Quere, professor of climate change science at the University of East Anglia, noted that emissions have rebounded before when economies recovered from shocks such as Covid and the global financial crisis, and said at a media briefing that a rebound is likely when the oil tensions go away.
Pierre Friedlingstein, director of the Global Carbon Budget Office at the University of Exeter, put the concern bluntly:
"A decline in fossil CO2 emissions is encouraging, but a reduction driven partly by geopolitical shocks is not a sustainable climate solution"
What is driving the drop
Researchers attribute the projected fall to two forces. The first is the expansion of renewable energy: solar panels, wind farms and electric vehicles are meeting two thirds of the increase in global energy demand. The second is geopolitical. The US-led war in Iran and the closure of the Strait of Hormuz caused a drop in oil consumption amid soaring crude prices.
By fuel, the picture is uneven:
- •Oil emissions are projected to drop 1.9%, which researchers called likely a short-term response to the energy shock triggered by the Iran conflict.
- •Gas emissions are set to fall 0.3%.
- •Coal emissions will rise 0.6%.
The researchers' message on what would make a lasting decline is clear. Friedlingstein, who led the study, said: "The long-term answer remains the rapid deployment of clean energy technologies."
Emissions still near record levels
The 2026 dip sits atop a decade of growth. Emissions from oil, gas and coal rose by 0.9% per year on average over the past decade and hit a record high in 2025. Even with the projected fall, fossil carbon dioxide emissions are still expected to reach 38.2 billion tonnes in 2026.
Counting land-use change, total CO2 emissions are projected to rise to 43.3 billion tonnes, up from 42.8 billion tonnes in 2025. Land-use emissions are climbing partly because of peat fires and forest degradation in southeast Asia, associated with drier conditions from an exceptionally strong El Nino this year.
Carbon budget nearly exhausted
The remaining carbon budget before warming exceeds 1.5C above pre-industrial levels stands at 150 billion tonnes. Researchers calculated that at current rates that budget would be exhausted in less than four years. Under the 2015 Paris agreement, nations agreed to keep warming well below 2C while pursuing efforts to limit it to 1.5C; the United Nations declared in September that the long-term 1.5C target would be missed in a matter of years.
Scientists behind the report say reducing greenhouse gas emissions from fossil fuels is crucial to limit the period of "overshoot" above 1.5C and bring temperatures back down quickly.
The findings were published in Earth System Science Data as the Global Carbon Budget report was released during the UN COP31 climate summit in Antalya, Turkey.
