Marine Research Days 2024

Professor Paul F. Wassmann

Department of Arctic and Marine Biology, University of Tromsö

Title: The indispensable holistic perspective of the Arctic Ocean

Abstract: The relatively small, but extremely resource-rich Arctic Ocean is under considerable pressure from a resource-hungry world. Our scientific approach is often characterized by national, sectorial approaches. However, the Arctic Ocean cannot be understood, let alone managed, without an all-encompassing, pan-Arctic perspective. In natural science, first steps have been taken to achieve such a holistic understanding of the contemporary Arctic Ocean, but to support a sustainable and wisely managed Arctic Ocean in the future, the integrative work has to be carefully and wholeheartedly expanded. Suggestions, such as the integration of national investigations and the education of a future generation of scientists, can improve the indispensable understanding of the entire Arctic, resulting in an adequate comprehension and management.

Associate Professor Carolin Löscher

Department of Biology, Southern Denmark University

Title: Who likes it dark and cold? Marine carbon fixation during the polar night

Abstract: The Arctic Ocean is characterized by strong seasonal variation in light and temperature, modulated by the cyclic progression and retreat of its ice cover. Anthropogenic climate change is a massive threat to the Arctic Ocean, with warming being a key threat leading, for instance, to changes in global ocean circulation and sea level rise.The light period in spring and summer has traditionally been recognized as the period of high biological productivity in Arctic open and coastal waters, driving pelagic food webs. But is that all?
In this presentation, I will present our latest results on dark and cold primary production carried out by a certain consortium of marine microbes in the Arctic Ocean. This process and the respective microbes might be highly relevant and their response to climate change could determine Arctic ecology to great extent.

Professor Marcelo Ketzer

Department of Biology and Environmental Sciences, Linnæus University

Title: Baltic Sea warming and related biogeochemistry change

Co-authors: Stranne, C., Chang, C., Rhamati-Abkenar, M., Hylander, S., Forsman, A., and Dopson, M.

Abstract: The Baltic Sea is considered a proxy or a “time machine” for the future shallow and coastal marine environments owing to its singular natural conditions, anthropogenic interference, ecosystem deterioration, and implementation of mitigation actions. Many studies have addressed the deterioration of Baltic Sea environment, but some topics are still open for debate. Here we present our latest results about one of these important topics: the effects of Baltic Sea warming on biogeochemistry and their implications for methane cycling. We found that long-term warming causes the thinning of the sulphate reduction zone and increases the chances of methane release on the seafloor. Our findings are based on (1) six years of observations in a bay in the Oskarshamn area, southeastern Sweden, that has been artificially heated (ca. 5°C in relation to control areas) for 50 years, and (2) a recently discovered major seafloor methane ebullition site in the Landsort Deep area, in the central Baltic Sea.

Associate Professor Inga Koszalka

Department of Meteorology, Stockholm University

Title: Wind drift, turbulent dispersion and algal blooms in the Baltic Sea

Abstract: Algal blooms pose a major environmental problem for the Baltic Sea’s marine ecosystem and its human stakeholders. Algal mats limit access to oxygen in the surface waters, downgrade aesthetic values of the sea and water quality and affect coastal industries. As the algal blooms are expected to intensify under the climate change and warming of sea waters, it is important to develop reliable hazard and hazard impact forecasting services. This is a tantalizing task however, owing to the complexity of physical and biological processes involved in algae growth and too sparse data to constrain marine ecosystem models.

I will present results from a project aiming to develop a forecast framework for algal blooms in the Baltic Sea and associated ecosystem and societal impacts. The framework makes use of Lagrangian (drifting) trajectory simulations. Drifter observations are used to evaluate the ocean model that is in turn used to force numerical trajectory simulations. I will also show implementation of an algae model of low complexity on trajectorires. The project focuses on consequences of algae blooms for the water quality on Gotland, in particular for the desalination plats producing drinking water from the sea water complementing the municipal water supply. The interaction with the stakeholders led to formulation of new scientific questions regarding the hazard impacts, which manifested during the extreme weather event Hans Storm in summer 2023.