GHG emissions: rates to reach unprecedented highs in 2024, with largest one-year increase (WMO bulletin)

"The levels of the three most abundant long-lived greenhouse gases, CO2 (carbon dioxide), CH4 (methane), and N2O (nitrous oxide), reached new records in 2024. From 2023 to 2024, CO2 in the global surface atmosphere increased by 3.5 ppm (parts per million), the largest one-year increase since modern measurements began in 1957. This increase was driven by continued fossil CO2 emissions, enhanced fire emissions, and reduced terrestrial/ocean sinks in 2024, which could signal a climate feedback. Given the dominant role of increasing atmospheric CO2 in global climate change, achieving net-zero anthropogenic CO2 emissions must be the focus of climate action. Sustaining and expanding greenhouse gas monitoring is critical to supporting such efforts", explains the World Meteorological Organisation in its latest bulletin on 16/10/2025.

These numbers are based on the WMO Global Atmosphere Watch, which observes the globally averaged surface concentrations of GHG and its evolution year per year.

Key figures of the WMO Greenhouse Gas Bulletin

• Record levels of the three major GHG in 2024: CO…