Nitrous oxide emissions from the upwelling area off Mauritania (NW Africa)

Nitrous oxide (N2O) flux densities across the ocean/atmosphere interface from the Mauritanian upwelling (16 degrees-18.5 degrees W, 16 degrees-21 degrees N) were computed with a simple upwelling model using N2O measurements from four cruises between 2006 and 2008 as well as wind data from the QuikSCAT satellite. The resulting N2O flux densities show a strong seasonality reflecting the wind-driven seasonality of the upwelling: N2O flux densities are highest in the northern part (19.5 degrees-21 degrees N) and show a decreasing trend towards the south. The summer periods with no upwelling (and thus associated with no or negligible N2O flux densities) are most pronounced in the southern part (16 degrees-17 degrees N). The mean seasonally and regionally weighted annual N2O emissions from the Mauritanian upwelling were estimated to 1.0 Gg N. This is low compared to other major upwelling areas (Arabian Sea, off Chile) indicating that N2O emissions from the Mauritanian upwelling are a minor source of atmospheric N2O. Citation: Wittke, F., A. Kock, and H. W. Bange (2010), Nitrous oxide emissions from the upwelling area off Mauritania (NW Africa), Geophys. Res. Lett., 37, L12601, doi: 10.1029/2010GL042442.