The global impact of biomass burning on tropospheric reactive nitrogen

In this chapter the authors first review their current understanding of both the anthropogenic and natural sources of reactive nitrogen compounds in the troposphere. Then the available observations of both surface concentration and wet deposition are summarized for regions with significant sources, for locations downwind of strong sources, and for remote sites. The obvious sparsity of the data leads to the next step: an attempt to develop a more complete global picture of surface concentrations and deposition of NOy with the help of global chemistry transport model (GCTM). The available source data are inserted into the GCTM and the resulting simulations compared with surface observations. The impact of anthropogenic sources, both downwind and at remote locations, is discussed and the particular role of biomass burning is identified