Global Carbon Emissions Outlook 2025
New data indicates that global fossil fuel consumption is projected to result in the highest release of planet-warming carbon dioxide to date in 2025. This projection coincides with UN climate talks (COP30) in Brazil and suggests that the rate of emissions reduction efforts is currently insufficient to meet international climate targets.
Despite this increase, the rate of emissions growth has slowed over the past decade due to the expansion of renewable energy sources. Separate analysis by the clean energy think tank Ember suggests that fossil fuel use in electricity generation has stabilized in 2025, primarily due to the rapid growth of solar power. This indicates a potential nearing of peak global emissions, although the exact timing remains undetermined.
Key Projections for 2025
The Global Carbon Budget team, comprising over 130 scientists from 21 countries, forecasts that carbon dioxide (CO2) emissions from fossil fuels and cement will increase to 38.1 billion tonnes of CO2 in 2025, an increase of 1.1% from 2024.
Emissions from land-use changes, such as deforestation, are projected to decrease compared to the previous year. This reduction is largely attributed to the conclusion of the El Niño weather pattern, which can intensify forest losses, and reflects a longer-term trend.
Consequently, total emissions from all human activities are expected to reach 42.2 billion tonnes of CO2 in 2025, a slight decrease from 42.4 billion tonnes in 2024.
Decadal Emissions Trends
The data shows that emissions growth has been slower in the past decade, averaging 0.3% per year, compared to 1.9% per year in the preceding decade. Over the last ten years, 35 countries demonstrated fossil fuel emissions reductions while simultaneously achieving economic growth, nearly doubling the number from the decade before.
Corinne Le Quéré, a professor of climate change science at the University of East Anglia, noted that while emissions are not decreasing at the rate required to address climate change, significant developments are occurring. She cited the growth in renewable energy, particularly in China and other regions, as a factor in the slower emissions growth rate.
Role of Renewable Energy in the Power Sector
The expansion of renewable energy is particularly evident in the power or electricity sector. Ember projects that electricity generated from fossil fuels will either stabilize or slightly decline this year, marking the first instance of such a trend since the COVID-19 pandemic. This stabilization occurs despite an observed increase in electricity demand, with wind and solar power meeting the additional demand.
Nicolas Fulghum, senior data analyst at Ember, stated that solar power is expanding at a significant rate, surpassing historical growth rates for other electricity sources. He emphasized the power sector's importance, identifying it as the largest emitting sector and anticipating its increased role in the energy system as electric vehicles and heat pumps become more prevalent.
Ember anticipates that emissions from fossil fuels used in electricity generation are stabilizing and may begin a sustained decline within a few years. This aligns with statements from the International Energy Agency, which projects that carbon emissions from energy systems could peak within the next few years based on current national policies.
Future Warming Projections
While a peak in emissions would represent a notable development in climate change mitigation, it would not halt global warming, as CO2 would continue to accumulate in the atmosphere, albeit at a reduced rate. Professor Pierre Friedlingstein, chair in mathematical modelling of climate systems at the University of Exeter, stated that continued CO2 emissions result in ongoing warming, and achieving zero net emissions is necessary to stop further warming.
A separate analysis by the Climate Action Tracker research group, released concurrently with COP30, indicates that global warming could reach 2.6°C above pre-industrial levels by the end of the century under current policies. This projection has remained largely consistent over recent years. Dr. Bill Hare from the Climate Action Tracker team highlighted the dual challenges of needing immediate action while facing potential negative outcomes if appropriate measures are not taken. He also acknowledged the opportunity presented by technological advancements.