Overview
- The WMO’s 21st greenhouse‑gas bulletin reports a 3.5 ppm rise in global mean CO2 from 2023 to 2024, the largest annual increase since modern measurements began.
- Atmospheric concentrations of CO2, methane and nitrous oxide each reached new records in 2024, according to the UN agency.
- The surge is attributed to ongoing human emissions, more frequent wildfires and weakening carbon sinks in oceans and terrestrial ecosystems.
- The year 2024 was the warmest on record, and heat trapped by greenhouse gases is intensifying extreme weather, WMO officials warn.
- CO2 growth rates have roughly tripled since the 1960s, rising from about 0.8 ppm per year to 2.4 ppm per year during 2011–2020, the agency notes.