With detailed analyses of water and sediment samples from the Gotland Basin, geoscientists from the Leibniz Institute for Baltic Sea Research succeeded in tracing the geochemical processes, which followed the Major Baltic Inflow in 2014/2015. Their conclusion: even very large amounts of oxygenated waters cause only small and temporary improvements of the nutrient situation in the central Baltic Sea.
Press Release Archive
On June 2, 2021, a two-week ship expedition led by the IOW will set out to marine protected areas in the Fehmarnbelt and the Oderbank. The aim of the research cruise is to carry out a comprehensive survey of the seabed’s condition, which, in addition to geophysical and geochemical properties, for the first time also includes the entire near-bottom food web – ranging from bacteria to fishes. The cruise is part of the pilot missions of the German Marine Research Alliance to investigate the impact of bottom trawling on marine protected areas in the North and the Baltic Sea.
Vibrio bacteria, including species that are harmful to humans, are a natural component of Baltic Sea plankton. As a consequence of climate change, they may become more common due to rising water temperatures and thus an increasing health risk. The BaltVib project, coordinated by the IOW, is investigating whether certain plant and animal communities such as seagrass and mussel beds naturally reduce near shore Vibrio abundance and how this effect can be supported through actively shaping the marine environment.
Climate change threatens marine biodiversity and thereby the stability of entire marine ecosystems. For phytoplankton, the impact of these changes can already be detected. By using state-of-the-art palaeoecology and biodiversity research methods, the new PHYTOARK research network will look back into 8,000 years of phytoplankton history archived in Baltic Sea sediments, to reconstruct responses to past changes of the environment due to climate fluctuations. The insights will be used to improve the assessment of impacts of present and future climate change.
With the help of highly resolved realistic model simulations physicists at the IOW have succeeded in depicting the so-called submesoscale dynamics in the Eastern Gotland Basin – the deepest of the large basins of the central Baltic Sea. Thus, the researchers gained the opportunity to investigate these highly dynamic phenomena, which – although being known for decades through satellite images – are up to now only scarcely studied and poorly understood because of their small size and short-lived nature.
Submesoscale dynamics in the heart of the Baltic Sea: High-resolution model reveals new insights
With the help of highly resolved realistic model simulations physicists at the IOW have succeeded in depicting the so-called submesoscale dynamics in the Eastern Gotland Basin – the deepest of the large basins of the central Baltic Sea. Thus, the researchers gained the opportunity to investigate these highly dynamic phenomena, which – although being known for decades through satellite images – are up to now only scarcely studied and poorly understood because of their small size and short-lived nature.
A team of climate modellers used an extensive multi-model ensemble to investigate the effects of climate change on the “dead zones” of the Baltic Sea. They showed that a reduction in the size of these areas can be achieved by 2100 if nutrient discharges are consistently reduced – despite climate change. For individual Baltic Sea regions, they determined an earlier visibility of changes than in others. They recommend intensifying observations there.
Microplastic pollution of the Baltic Sea: New insights into behaviour, sinks and reduction measures
In order to assess the impact of microplastics on the oceans, it is necessary to know their quantity and their behaviour in the sea. So far, this knowledge is still incomplete because of a high analytical effort and high costs. For the Baltic Sea, comprehensive calculations of microplastics emissions are now available for urban pathways. Together with 3D-model simulations they provide new insights into transport, behaviour and deposition of microplastics in the marine environment.
From February 25 to March 23, 2021, a team of physicists and geologists from Warnemünde, Kiel and Szczecin will be underway in the northern Baltic Sea to investigate the dynamics of winterly deep water circulation. Besides recording the current hydrodynamic conditions near and under the sea ice of the Gulf of Bothnia, the program includes sedimentological and geophysical studies to investigate sediment erosion and deposition characteristics induced by deep-water movement. A further aim is to reconstruct the history of deep water circulation in the northern Baltic Sea during Holocene climate variations recorded in older sediments.
In search of the “Golden Spike”: On the role of microplastics in defining the Anthropocene
In a recently published discussion paper, Juliana Ivar do Sul and Matthias Labrenz, environmental scientists at the IOW, focus on the topic of microplastics from a geological perspective. They discuss whether the omnipresent plastic particles could be used to identify the beginning of a new, not-yet formalised geological epoch, the Anthropocene, in geo-archives such as sediment cores. Moreover, microplastics could be used at a suitable location to establish the so called Golden Spike, which, by definition, is used in geology to document the beginning of an epoch, period or era.