Greenhouse gas emissions worldwide - statistics & facts
Despite a flurry of climate pledges, global greenhouse (GHG) emissions have continued to rise, reaching a new high of 53 billion metric tons of carbon dioxide equivalent (GtCO₂e) in 2023. With the remaining global carbon budget to limit warming to 1.5 degrees Celsius shrinking rapidly, and 2024 confirmed as the warmest year on record, the race is on to reach net zero emissions by mid-century and avoid the worst impacts of climate change.
The remaining carbon budget to have a 50 percent chance of limiting warming to 1.5 degrees Celsius is expected to be used up within six years if emissions continue at their current rate. As such, rapid emissions cuts are needed, requiring more ambitious climate pledges from decision makers and accelerated implementation.
CO₂ emissions continue to break records
Global CO₂ emissions from fossil fuels have risen by more than 60 percent since 1990 to reach a record high of 37 GtCO₂e in 2023, and early projections show they grew a further one percent in 2024. Despite this increase, CO₂ emissions have slowed in the past decade, owing to the accelerated deployment of clean energy technologies. Nevertheless, atmospheric CO₂ concentrations are now more than 50 percent above pre-industrial levels, having climbed to almost 425 parts per million in 2024. CO₂ is the primary GHG emitted through human activities and the largest contributor to climate change, having caused 70 percent of global surface temperature rise since 1851.Biggest sources of GHG emissions
The power sector is the single largest source of GHG emissions from human activities, with annual emissions of roughly 15 GtCO₂e. Almost 70 percent of power sector emissions are produced by coal-fired power plants, which are still the largest sources of electricity generation worldwide. Transportation was the second most polluting sector in 2023, making up 16 percent of global emissions. The majority of emissions from this sector – which have almost doubled since 1990 - stem from road vehicles, particularly passenger cars.Who are the world’s biggest emitters?
China was the world’s biggest GHG emitter in 2023, having produced around 30 percent of total global emissions that year. The Asian country’s emissions have risen almost threefold since the turn of the century to more than 13 GtCO₂e per year, owing to rapid industrialization and economic growth. A similar pattern has been observed in other developing countries, including India, where emissions have doubled since 2000 to become the third highest globally. In comparison, the U.S., which was the biggest emitter up until 2005, has cut its emissions by 17 percent since 2000. Nevertheless, the U.S. remains the biggest emitter in history by far, with cumulative emissions of more than 500 GtCO₂ since the Industrial Revolution began.Emissions need to be cut more rapidly
According to the IPCC’s sixth assessment report, global GHG emissions need to be cut by at least 43 percent from 2019 levels by 2030 to keep global temperatures within the 1.5 degrees Celsius limit. However, under current policies, it is projected that there will be an emissions gap of 24 GtCO₂e to be consistent with this target. Despite considerable growth in clean energy deployment, the shift towards renewables and electrification has not been fast enough to displace fossil fuels as the dominant primary energy sources worldwide. As a result, forecasts show global investment in clean energy technologies, including battery storage and renewables, will need to double from current levels by 2030 to be in line with achieving net zero by 2050.The remaining carbon budget to have a 50 percent chance of limiting warming to 1.5 degrees Celsius is expected to be used up within six years if emissions continue at their current rate. As such, rapid emissions cuts are needed, requiring more ambitious climate pledges from decision makers and accelerated implementation.
