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iAbstract To understand the mechanisms governing the dispersal, transformation and deposition of pollutants from the atmosphere to coastal waters, coastal meteorology must first be consid-ered. This study focuses on the deposition of atmospheric inputs of inorganic nitrogen compounds (NO, NO2, HNO3, NH3) into the southern North Sea. The three-dimensional Eulerian mesoscale transport model METRAS is used in this study to simulate meteorol-ogy in the coastal regions and the SEMA box model and the chemistry transport model MECTM were applied to determine the impact of meteorology and chemical transforma-tions on deposition and the resultant nitrogen loads into the coastal waters. The studies are performed for the 1998 ANICE field campaign. The results of the METRAS meteorology runs were validated against observations using a series of programs developed for that purpose. With the model system METRAS/MECTM the influence of meteorological phenomena and gas phase chemical transformations on ni-trogen deposition are studied and total N deposition loading to the study area is calculated. This study shows that even though emissions play a large role in nitrogen loading, the sec-ondary pollutants arising form the chemical transformations have a much greater impact on deposition. It is also shown that meteorology can direct an input event (June 20th), but a combination of meteorological influences such as wind speed and wind direction, and chemical transformations can also have a significant impact (June 18th). The aerosol box model SEMA study shows that aerosol formation in the coastal region would greatly alter the input calculated from gas phase-only chemical transport models, and is an important contributing process. i