Award: OCE-1756757

We worked in collaboration with the University of Hawaii and scientists from the University of Kiel and GEOMAR to investigate the rate of gas exchange between the waters in the Baltic Sea and the atmosphere. Knowing the ocean/atmosphere gas exchange rate is important for the uptake or release of gases by the ocean such as, for example, the uptake of anthropogenic CO2. Whereas the knowledge of gas exchange rates between ocean and atmosphere is increasingly better known and typically characterized as a function of wind speed, there are still some open questions concerning its controlling factors. One of the factors that influence the gas exchange rate are surfactants (surface films typically of organic origin). We chose the Baltic Sea for this experiment as there are regions with significant surfactants. Additionally, the wind fetch (distance over which wind can induce turbulence in the surface waters) in the Baltic Sea is limited which also influences the gas exchange rates. Due to these conditions, we expected lower gas exchange rates in the Baltic Sea and indeed the results from the experiment confirm this hypothesis. These results are of interest for scientists who are working on inventories of gases in the ocean. Specifically, they confirm that we cannot simply use a uniform gas exchange for the entire ocean but have to consider deviations from the general open ocean gas exchange rates in areas where surfactants and geometry are major factors such as in certain coastal regions of the ocean. The project involved students from the University of Hawaii, our collaborative partner in the U.S., as well as from German institutions. The students obtained training in sampling and analytical methods and will use the data for their theses and resulting publications. Last Modified: 11/12/2023 Submitted by: PeterSchlosser