MOSES Sternfahrt-10, Elbe water distribution and dispersion of pollutants from the Elbe outflow into the Northern Sea (German Bight), in 2023

The Sternfahrt-10 of the MOSES campaign, from 29th August until the 15th of September 2023, had two objectives. One was to follow the dispersion of pollutants, previously observed during the Elbe-Freshwater and Elbe-Tidal cruises, transported by the Elbe water into the North Sea. And second, on this occasion, the distribution of the Elbe water within the German Bight should be followed. To realize this, two drifter groups were deployed in the southern and, respectively, northern branch of the Elbe valley, which were continuously monitored by scientists at the Hereon institute. Further, the drifters were subsequently followed by three ships (RV Ludwig Prandtl, RV Littorina, RV Mya II), for in total three weeks, to measure hydrographic parameters multiple times along their journey. Additionally, to this stationary sampling, basic hydrographic parameters and dissolved methane were measured continuously along the tracks (content of the presented dataset). To ensure the comparability of the data from all three vessels a container was transferred from ship to ship. This "MOSES laboratory-container" was equipped with several sensors, amongst others a pocket FerryBox and a Greenhouse Gas Analyser (Los Gatos). The Ludwig Prandtl started the campaign on August 29th in Cuxhaven and deployed the drifters in the respective areas of the Elbe outflow section of the German Bight. Until the 1st of September the crew followed the drifters to sample this water body. Not all drifters could be reached every day, because it was too shallow, in this case the vessels occupied MOSES hydrographic stations from previous Sternfahrt cruises. On September 4th the vessel Littorina took over and started the second part of the campaign navigating from Cuxhaven to Heligoland covering as many drifter positions as possible. Until the 7th of September the crew sampled in the north eastern part of Heligoland up to Büsum. The handover of the container for the last episode of the cruise took place in Heligoland to the vessel Mya II. From there the crew navigated on September 12th towards west off the island Amrum. In the following days until September 14th, they sampled west off Heligoland to west off St. Peter-Ording. For more details about the exact tracks of the ships, have a look at the added map. More detailed information about the MOSES project and the Sternfahrten, see article cited in references.