Treating uncertainty in models of the atmospheric chemistry of nitrogen compounds

The paper presents a highly simplified model of the long-range transport and deposition of nitric oxide, nitrogen dioxide, gaseous nitric acid and nitrate aerosol over NW Europe. A ‘constant drizzle’ representation of wet removal of gaseous nitric acid and nitrate aerosol is developed in addition to the representation of dry deposition using appropriate deposition velocities. An analysis of the sensitivity of dry and wet deposition rates of oxidized nitrogen species at a remote, receptor site to the individual model parameters is described. This analysis is extended using latin hypercube sampling to an evaluation of the uncertainties in modelled dry and wet deposition and the contribution played by each model input parameter.