Global atmospheric monitoring networks, including NOAA’s Global Monitoring Laboratory, recorded an atmospheric N₂O concentration of approximately 336.0 parts per billion (ppb) in 2024 — the highest level in at least 800,000 years of ice core records.
Historical Trend
Pre-industrial N₂O concentration was approximately 270 ppb. The current rate of increase is about 1.0–1.3 ppb per year, driven by agricultural emissions (67%), industrial sources (10%), and combustion (15%).
2024 Global Mean
336.0 ppb (±0.1)
Measurement Methods
Atmospheric N₂O is monitored using gas chromatography with electron capture detection (GC-ECD) and infrared spectroscopy at stations including Mauna Loa (Hawaii), Alert (Canada), Cape Grim (Australia), and over 50 other global sites in the WMO Global Atmosphere Watch network.