Scientists project that global carbon dioxide emissions from fossil fuels will decrease by 0.4 percent this year, after having grown by 0.8 percent each year on average from 2019 to 2025.
But the dip may not last. The lower emissions are probably driven by high oil prices stemming from the Iran war, researchers report November 9 in Nature Climate Change.
Global emissions probably would have grown again this year without the energy shock of the Iran war, says Glen Peters, a climate scientist at the Center for International Climate Research in Oslo, Norway. “So the energy transition that’s happening … it’s not quite big enough to get emissions heading downward yet.”
For the study, Peters and his colleagues used data on countries’ electric vehicle stocks and wind and solar energy generation to project those technologies impacts on global fossil CO2 emissions through 2028. The team used the generative AI model Claude to source data and write code for analysis.
By year’s end, global emissions will reach 38.24 gigatons, the researchers found, which is about 0.16 gigatons less than were emitted in 2025. For comparison, annual global emissions fell by nearly two gigatons in 2020 due to the COVID-19 pandemic and by about 0.5 gigatons in 2009 because of the global financial crisis.
If electric vehicle sales and solar and wind capacity continue growing at the rates they did in 2026, those technologies should counteract about 63 percent of the growth in emissions from 2025 to 2028 — or help avoid about 1.64 gigatons of added emissions.
The results indicate that the energy transition needs to accelerate if humankind is to realize consistently declining emissions, though EVs, solar and wind are already having a large impact. Without the offset in emissions provided by those technologies, global emissions would have risen by 1.9 percent each year on average from 2019 to 2025, the researchers note.
It’s very hard to say exactly how long it will take for humanity to reach peak emissions, Peters says. However, he notes, “the fact that we’re talking about this means that we’re close to that point.”