Investigating air quality in the marine environment of the North and Baltic Sea with MAX-DOAS measurements

This thesis presents MAX-DOAS measurements of the air pollutants NO2 and SO2 in the marine environment of the North and Baltic Sea and the surrounding coastal areas. As the first part, the results from more than three years of MAX-DOAS measurements on the island Neuwerk in the German Bight are presented. As the second part, a novel application of an "onion peeling" like approach to MAX-DOAS measurements of shipping emissions on Neuwerk was developed, aiming at investigating the strong horizontal inhomogeneities in NO2 over a shipping lane. In the third part, expanding the research area from the German North Sea coast to the entire greater North Sea area and the German part of the Baltic Sea, shipborne MAX-DOAS measurements for air quality assessment have been performed for the first time on a regular basis in this area on routinely conducted survey cruises in cooperation with the German Federal Maritime and Hydrographic Agency (Bundesamt für Seeschifffahrt und Hydrographie, BSH).