WMO’s 2025 Greenhouse Gas Record: What the Global Numbers Actually Measure
World · Atmospheric observations WMO’s 2025 greenhouse gas record What the global numbers actually measure. 426.8 ppm · Global surface CO₂ annual mean, 2025 NEWJINMEDIA · October 30, 2026 A balloon carries an AirCore atmospheric-sampling package in an undated NOAA archive photograph. Credit: NOAA Global Monitoring Laboratory. Source · Reuse terms Air-sampling flasks connected to a preparation manifold in NOAA’s October 2017 network newsletter. Credit: NOAA Global Monitoring Laboratory. Source · Reuse terms A global record built from local air samples WMO reports record greenhouse gas levels in 2025; the global figures measure accumulated gases, not one year’s emissions. The bulletin released October 27 puts the global surface average for carbon dioxide at 426.8 parts per million. Methane reached 1,948 parts per billion and nitrous oxide 339.1 parts per billion. These are observations for 2025, assembled and analyzed for the 2026 publication—not a completed account of the current ...