Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2012 May 5;367(1593):1245-55.
doi: 10.1098/rstb.2011.0360.

Global oceanic production of nitrous oxide

Alina Freing  1 , Douglas W R Wallace, Hermann W Bange
Affiliations

Global oceanic production of nitrous oxide

Alina Freing et al. Philos Trans R Soc Lond B Biol Sci. .

Abstract

We use transient time distributions calculated from tracer data together with in situ measurements of nitrous oxide (N(2)O) to estimate the concentration of biologically produced N(2)O and N(2)O production rates in the ocean on a global scale. Our approach to estimate the N(2)O production rates integrates the effects of potentially varying production and decomposition mechanisms along the transport path of a water mass. We estimate that the oceanic N(2)O production is dominated by nitrification with a contribution of only approximately 7 per cent by denitrification. This indicates that previously used approaches have overestimated the contribution by denitrification. Shelf areas may account for only a negligible fraction of the global production; however, estuarine sources and coastal upwelling of N(2)O are not taken into account in our study. The largest amount of subsurface N(2)O is produced in the upper 500 m of the water column. The estimated global annual subsurface N(2)O production ranges from 3.1 ± 0.9 to 3.4 ± 0.9 Tg N yr(-1). This is in agreement with estimates of the global N(2)O emissions to the atmosphere and indicates that a N(2)O source in the mixed layer is unlikely. The potential future development of the oceanic N(2)O source in view of the ongoing changes of the ocean environment (deoxygenation, warming, eutrophication and acidification) is discussed.

PubMed Disclaimer

Figures

Figure 1.
Figure 1.
Shelf nitrous oxide (N2O) production rates (nmol kg–1 yr–1) calculated from N2O data versus shelf N2O production rates (nmol kg–1 yr–1) calculated using equation (2.3).
Figure 2.
Figure 2.
Available nitrous oxide depth profiles extracted from the MEMENTO database, version March 2009 [20].
Figure 3.
Figure 3.
Global transient time distribution mean age (in years) in (a) 75 m, (b) 250 m and (c) 700 m.
Figure 4.
Figure 4.
Section along 110° W (averaged between 100° W and 120° W). (a) Predicted [N2O] (nmol kg–1) according to N2OPRdepth. (b) Predicted [N2O] (nmol kg–1) according to N2OPRtemp. (c) Measured [N2O] (nmol kg–1) from Nevison et al. [33] and Farías et al. [34].
Figure 5.
Figure 5.
Global [N2O] (nmol kg–1) distribution in 200 m depth estimated using equations (2.7) with N2OPRdepth (a) and equation (2.7) using N2OPRtemp (b). (a,b) White areas in the Arabian Sea represent concentrations exceeding 40 nmol kg–1. Annual N2O production (μmol m–2 yr–1) via nitrification integrated over the water column estimated using (c) equation (2.1) and (d) equation (2.2).
See this image and copyright information in PMC

References

    1. IPCC 2007. Climate change 2007: the physical science basis. Contribution of working group I to the fourth assessment report of the intergovernmental panel on climate change (eds Solomon S., Qin D., Manning M., Chen Z., Marquis M., Averyt K. B., Tignor M., Miller H. L.), p. 996 Cambridge, UK: Cambridge University Press
    1. WMO 2011. Scientific assessment of ozone depletion: 2010, global ozone research and monitoring project. Report no. 52 Geneva, Switzerland: WMO
    1. Forster P., et al. 2007. Changes in atmospheric constituents and in radiative forcing. In Climate change 2007: the physical science basis. Contribution of working group I to the fourth assessment report of the intergovernmental panel on climate change (eds Solomon S., Qin D., Manning M., Chen Z., Marquis M., Averyt K. B., Tignor M., Miller H. L.), pp. 129–234 Cambridge, UK: Cambridge University Press
    1. Bange H. W. 2006. New directions: the importance of the oceanic nitrous oxide emissions. Atmos. Environ. 40, 198–199 10.1016/j.atmosenv.2005.09.030 (doi:10.1016/j.atmosenv.2005.09.030) - DOI
    1. Denman K. L., et al. 2007. Couplings between changes in the climate system and biogeochemistry. In Climate change 2007: the physical science basis. Contribution of working group I to the fourth assessment report of the intergovernmental panel on climate change (eds Solomon S., Qin D., Manning M., Chen Z., Marquis M., Averyt K. B., Tignor M., Miller H. L.), pp. 499–587 Cambridge, UK: Cambridge University Press

Publication types