Inverse modeling estimates of the global nitrous oxide surface flux from 1998–2001
Article first published online: 11 FEB 2006
Copyright 2006 by the American Geophysical Union.
Global Biogeochemical Cycles
Volume 20, Issue 1, March 2006
How to Cite
2006), Inverse modeling estimates of the global nitrous oxide surface flux from 1998–2001, Global Biogeochem. Cycles, 20, GB1008, doi:10.1029/2004GB002443., , , , , and (
- Issue published online: 11 FEB 2006
- Article first published online: 11 FEB 2006
- Manuscript Accepted: 10 NOV 2005
- Manuscript Revised: 24 OCT 2005
- Manuscript Received: 29 DEC 2004
- biosphere-atmosphere interactions;
- nitrous oxide;
- nutrient cycling
 Measurements of nitrous oxide in air samples from 48 sites in the Cooperative Global Air Sampling Network made by NOAA/ESRL GMD CCGG (the Carbon Cycle Greenhouse Gases group in the Global Monitoring Division at the NOAA Earth System Research Laboratory in Boulder, Colorado) and the three-dimensional chemical transport model TM3 were used to infer global nitrous oxide fluxes and their uncertainties from 1998–2001. Results are presented for four semihemispherical regions (90°S–30°S, 30°S to equator, equator to 30°N, 30°N–90°N) and six broad “super regions” (Southern Land, Southern Oceans, Tropical Land, Tropical Oceans, Northern Land, and Northern Oceans). We found that compared to our a priori estimate (from the International Geosphere-Biosphere Programme's Global Emissions Inventory Activity), the a posteriori flux was much lower from 90°S–30°S and substantially higher from equator to 30°N. Consistent with these results, the a posteriori flux from the Southern Oceans region was lower than the a priori estimate, while Tropical Land and Tropical Ocean estimates were higher. The ratio of Northern Hemisphere to Southern Hemisphere fluxes was found to range from 1.9 to 5.2 (depending on the model setup), which is higher than the a priori ratio (1.5) and at the high end of previous estimates. Globally, ocean emissions contributed 26–36% of the total flux (again depending on the model setup), consistent with the a priori estimate (29%), though somewhat higher than some other previous estimates.