Global overview of GHG emissions

Breakdown of total GHG emissions (excluding LULUCF*) in 2023

* See glossary.
Note : distribution calculated according to the GWP of each gas over 100 years. CO₂ = carbon dioxide; N₂O = nitrous oxide; CH₄ = methane.
The emissions figures used in this section (EDGAR and IEA) are estimates independent of the official national inventories compiled by the UNFCCC. They may therefore differ significantly due to different methodologies (emission factors, sectoral breakdown, data sources, etc.). They provide comparable data for the whole world since 1970.
Source : SDES, based on EDGAR, 2024

The Global Warming Potential (GWP) is used to calculate the impact of emissions of each gas on the greenhouse effect, in tonnes ofCO₂ equivalent(see glossary). The GWP of a gas depends on the period over which it is calculated (see p. 13). For example, the GWP of methane is 28 to 30 when calculated over 100 years, and 84 when calculated over 20 years. With the 100 year GWP (the most commonly used ), CO₂ accounts for three quarters of GHG emissions in 2023.

In 2023, global greenhouse gas emissions (excluding LULUCF) reached 53 Gt CO₂ eq. They have more than doubled since 1970, increasing by 62% between 1990 and 2023. Depending on the year, the LULUCF sector contributes positively or negatively to global GHG emissions, mainly depending on the scale of forest fires (+1,537 Mt CO₂ eq in 2023, -130 in 2022).

Worldwide GHG emissions by fuel

Note: emissions included here are those linked to fossil fuel combustion and fugitive emissions (see glossary).
Source: IEA, 2025

In 2023, economic activity continued to grow after the slowdown caused by the pandemic. GHG emissions from energy combustion followed, rising by 1.5%. This increase was driven by fossil fuels : coal (+1.9%), oil (+1.3%) and natural gas (+1.2%). Emissions from other fuels (waste, biofuels¹) stagnated (+0.1%).

Coal combustion generated 42% of global emissions (up 8 points on 1971), compared with 34% for oil (down 15 points) and 22% for natural gas (up 8 points).

Since 1971, global GHG emissions linked to energy combustion have multiplied by 2.3.

¹ Only methane and nitrous oxide emissions are counted for biofuels.

World primary energy mix

Source: IEA, 2025

Energy-related emissions depend on the level of energy consumption (up 150% between 1973 and 2023) and on the primary energy mix (see glossary), which remains dominated by fossil fuels worldwide in 2023 (oil, coal and natural gas: 81% of the total).

Oil remains the world's leading energy source, although its share fell by 16 points between 1973 and 2023, mainly to the benefit of natural gas (+7 points) and nuclear power (+4 points). However, coal remains the main source of emissions. Indeed, it has a much higher emission factor than natural gas and oil (see p. 90). Coal consumption, which rose sharply in the 2000s, has tended to stagnate or even decline in recent years. Although stable overall since 1971, the share of renewable energies has grown slightly over the past ten years, reaching 14% of the mix in 2023.

Sectoral breakdown of GHG emissions from energy combustion in 2023

* Including cogeneration and self-generation.
Source: IEA, 2025

In 2023, power generation remained the world's leading GHG-emitting sector, accounting for 40% of total emissions from energy combustion. It was followed by transport (22%) and industry (16%, including construction). In China, industry and the energy sector (electricity and non-electricity) together accounted for 80% of GHG emissions from energy combustion, compared with a world average of 60%. Transportation is more important in the United States (35%) and the European Union (33%), as are the residential and services sectors. Worldwide, fugitive emissions (see glossary) accounted for 9% of emissions linked to energy combustion.