Abstract
Data derived during three intensive sampling campaigns conducted at a rural site on the North Sea coast of the UK were used to examine the influence of airmass back trajectory on the overall concentration and budget of reactive nitrogen. Concentrations of nitric oxide, nitrogen dioxide, nitrous acid, nitric acid, aerosol nitrate, PAN, and NO sub(y) were measured. Size-fractionated aerosol samples were collected using a cascade impactor, and a condensation particle counter was employed. Meteorological data were collected and used to estimate airmass back trajectories. Results indicated that air that had traveled over sea for at least a few days contained enhanced total inorganic NO sub(3) compared to land-based trajectories. Nitrogen oxides/NO sub(y) ratios were highest in winter and in recently contaminated airmasses arriving off the land. Air arriving from the land contributed significantly to ammonia fluxes to the sea.