Global carbon emissions from fossil fuels reached record levels in 2023, according to the Global Carbon Project science team’s results. This report, published in the Earth System Science Data journal, projects total CO2 emissions to be 40.9 billion tonnes in 2023. The research team includes researchers from the University of Exeter, the University of East Anglia (UEA), the CICERO Center for International Climate Research, Ludwig-Maximilian-University Munich, and 90 other institutions around the world.
Carbon emissions are decreasing in some regions, including Europe and the USA, but are rising worldwide. The annual Global Carbon Budget shows a 1.1% rise in 2023 compared to 2022. Researchers say that global action is not happening fast enough to stop the impact of climate change. For example, emissions coming from deforestation are likely to drop slightly but remain too high to be offset by current levels of reforestation and afforestation.
2023 results are higher than 2022’s, but they are still part of a plateau observed in the past ten years. Nevertheless, researchers say this is far from the reduction in emissions that is urgently needed to meet global climate targets. “The impacts of climate change are evident all around us, but action to reduce carbon emissions from fossil fuels remains painfully slow,” said Professor Pierre Friedlingstein of Exeter’s Global Systems Institute, who led the study. “It now looks inevitable we will overshoot the 1.5°C target of the Paris Agreement, and leaders meeting at COP28 will have to agree rapid cuts in fossil fuel emissions even to keep the 2°C target alive.”
This team also calculated the remaining carbon budget before the 1.5°C target is breached over multiple years, not just for a single year. At the current level of emissions, the Global Carbon Budget team estimates a 50% chance global warming will exceed 1.5°C consistently in just seven years.
This team acknowledges that this value is subject to significant uncertainties, primarily due to the uncertainty of any further warming coming from other non-carbon sources. What’s clear, however, is that the remaining carbon budget – and therefore the time left to meet the 1.5°C target and avoid the worse impacts of climate change – is running out fast.
“The latest CO2 data shows that current efforts are not profound or widespread enough to put global emissions on a downward trajectory towards Net Zero, but some trends in emissions are beginning to budge, showing climate policies can be effective,” said Professor Corinne Le Quéré, Royal Society Research Professor at UEA’s School of Environmental Sciences. “Global emissions at today’s level are rapidly increasing the CO2 concentration in our atmosphere, causing additional climate change and increasingly serious and growing impacts. All countries need to decarbonise their economies faster than they are at present to avoid the worse impacts of climate change.”
The Global Carbon Budget report is developed by an international team of more than 120 scientists and provides an annual update on carbon emissions, building on established methodologies in a fully transparent manner. The 2023 edition is the 18th annual report.
Friedlingstein P, O’Sullivan M, Jones M, et al. (2023) Global Carbon Budget 2023. Earth System Science Data, https://doi.org/10.5194/essd-15-5301-2023