Data
Nitrous oxide, global annual mean
Annual mean nitrous oxide in dry air averaged over NOAA's global network of marine surface air-sampling sites, since 2001.
Latest value
338.85ppb
Global mean of marine surface sites, 2025 (preliminary). Version 2026-09.
Nitrous oxide, global annual mean (parts per billion)
Show as a table
| Period | Value (ppb) | Range | Status |
|---|---|---|---|
| 2001 | 316.36 | 316.24 to 316.48 | final |
| 2002 | 316.94 | 316.81 to 317.07 | final |
| 2003 | 317.63 | 317.49 to 317.77 | final |
| 2004 | 318.25 | 318.13 to 318.37 | final |
| 2005 | 318.91 | 318.78 to 319.04 | final |
| 2006 | 319.82 | 319.69 to 319.95 | final |
| 2007 | 320.44 | 320.33 to 320.55 | final |
| 2008 | 321.50 | 321.38 to 321.62 | final |
| 2009 | 322.27 | 322.13 to 322.41 | final |
| 2010 | 323.18 | 323.05 to 323.31 | final |
| 2011 | 324.21 | 324.09 to 324.33 | final |
| 2012 | 325.05 | 324.93 to 325.17 | final |
| 2013 | 325.94 | 325.82 to 326.06 | final |
| 2014 | 327.09 | 326.98 to 327.20 | final |
| 2015 | 328.17 | 328.05 to 328.29 | final |
| 2016 | 328.95 | 328.83 to 329.07 | final |
| 2017 | 329.74 | 329.63 to 329.85 | final |
| 2018 | 330.90 | 330.78 to 331.02 | final |
| 2019 | 331.88 | 331.76 to 332.00 | final |
| 2020 | 333.00 | 332.94 to 333.06 | final |
| 2021 | 334.27 | 334.24 to 334.30 | final |
| 2022 | 335.61 | 335.58 to 335.64 | final |
| 2023 | 336.68 | 336.65 to 336.71 | final |
| 2024 | 337.71 | 337.69 to 337.73 | final |
| 2025 | 338.85 | 338.83 to 338.87 | preliminary |
Where it comes from
- Producer
- NOAA Global Monitoring Laboratory · Trends in globally-averaged methane, nitrous oxide and sulphur hexafluoride
- Version
- 2026-09
- Fetched
- 2026-10-04 (automatically), 2,455 bytes
- Fingerprint
- sha256 4ef7de075201af680fe28b262d4df8f092303c3450d1a7d8c1884e5c3bff070dETag "997-65af9c509e106" · Last-Modified Tue, 08 Sep 2026 14:44:19 GMT
- Copies
- No Wayback copy recorded yet.Our copy of the exact file
- Cite the producer
- Lan, X., K.W. Thoning, and E.J. Dlugokencky: Trends in globally-averaged CH4, N2O, and SF6 determined from NOAA Global Monitoring Laboratory measurements. Version 2026-09, https://doi.org/10.15138/P8XG-AA10
What was done to it
Read n2o_annmean_gl.csv, created by NOAA on 5 September 2026. The vintage is the year and month of that creation date, which is how NOAA labels its versions.
Code: pipeline/src/envdash/transforms/air/noaa_ch4_n2o.py · code sha256 10dc38222688b6d5… · inputs 4ef7de075201…
Lower and upper are the mean minus and plus NOAA's stated uncertainty, which the file defines as the standard deviations of 100 bootstrap (network) and 100 Monte Carlo (measurement) global averages taken in quadrature (one standard deviation).
Code: pipeline/src/envdash/transforms/air/noaa_ch4_n2o.py · code sha256 10dc38222688b6d5… · inputs 4ef7de075201…
The last year is marked preliminary because the file states that the data for the last year are subject to change.
Code: pipeline/src/envdash/transforms/air/noaa_ch4_n2o.py · code sha256 10dc38222688b6d5… · inputs 4ef7de075201…
What it covers
- Geography
- Global mean of marine surface sites
- Basis
- Dry-air mole fraction; NOAA's global average of its marine surface air-sampling network, from smoothed site records weighted by latitude.
- Unit
- parts per billion (ppb)