Multiple drivers of Earth system changes in the Baltic Sea region

Background and objective

Societal efforts to manage the marine, terrestrial and atmospheric environment of the Baltic Sea region and to promote a sustainable human presence – meeting present societal needs without deleterious impacts on the conditions passed on to future generations – are hindered by incomplete understanding of the complex of drivers, interactions and historical factors responsible for the current detrimental state of the environment and ecosystems. Such gaps in understanding inhibit reliable predictions of how the marine system and the surrounding land areas, watershed and atmosphere may respond to ongoing and future projected trends in multiple drivers, or to management interventions.

The Second Assessment of Climate Change for the Baltic Sea Basin focused on regional climate change and its associated impacts, including the documentation of regional detection and attribution efforts, but also highlighted a mixture of interwoven factors, such as eutrophication, pollution, fisheries, hydrographic engineering, agricultural and forestry practices and land cover change, responsible for the current situation and of potential importance as drivers of future changes. Current observational datasets, system understanding and available modelling tools are insufficient to ascribe key dimensions of change to a single or even dominant factor or to construct credible scenarios of future changes. Two overall problem complexes concern the causes and impacts of eutrophication and climate change. Studies in these areas have traditionally been pursued by separate communities of researchers using different methods and approaches, adopting a diversity of baseline datasets and scenarios, and focusing on different spatial and temporal scales. There has likewise been relatively little collaboration across the science-social science divide, or between terrestrial, freshwater and marine scientists in related fields.

There is a need for increased cooperation among researchers having specialised knowledge of different components of the coupled biophysical-societal system of the Baltic Sea region, in the dynamics of which an understanding of the inter-related role of multiple drivers and their impacts on regional Earth system changes may be sought. Key disciplines include meteorology and climate science, oceanography, hydrology, marine, terrestrial and freshwater ecology, microbiology and biogeochemistry, as well as economists, human geographers, political scientists and engineers. A more integrated researcher effort needs to be complemented with an identification of key missing datasets on drivers and responses, their variations over past decades and across the region. A consensus should be sought on the relevant interactions to explore and the key knowledge gaps that need to be filled in order to develop reliable predictive models, applicable at the regional scale of the Baltic Sea.

Description of tasks (or Terms of Reference)

Potential activities include the organization of conferences and workshops to bring different disciplines together and do syntheses, agree on datasets and data gaps, scope out the system to model with its key components and their interactions, and design model experiments. The development of coupled Earth system models capturing interactions between atmospheric, marine and land compartments/processes, as well as responses to anthropogenic forcing such as emissions and land use is a key long-term goal.

News and Events

Baltic Earth Workshop on
Multiple drivers for Earth system changes in the Baltic Sea region
Tallinn University of Technology, Tallinn, Estonia, 26- 27 November 2018
Co-organized by Helmholtz-Zentrum Hereon, Leibniz Institute for Baltic Sea Research and Tallinn University of Technology in collaboration with with BONUS, HELCOM and ICES


Baltic Earth session at EGU General Assembly 2019
Climate and other drivers of change: Interlinkages, ramifications and impacts in coastal regions
Vienna, Austria, 7-12 April 2019


Outcomes (Data, reports, publications, events)

Main outcome of this WG is the Baltic Earth Assessment Report in Earth System Dynamics:

Reckermann, M., Omstedt, A., Soomere, T., Aigars, J., Akhtar, N., Bełdowska, M., Bełdowski, J., Cronin, T., Czub, M., Eero, M., Hyytiäinen, K. P., Jalkanen, J.-P., Kiessling, A., Kjellström, E., Kuliński, K., Larsén, X. G., McCrackin, M., Meier, H. E. M., Oberbeckmann, S., Parnell, K., Pons-Seres de Brauwer, C., Poska, A., Saarinen, J., Szymczycha, B., Undeman, E., Wörman, A., and Zorita, E.: Human impacts and their interactions in the Baltic Sea region, Earth Syst. Dynam., 13, 1–80,, 2022.

WG members

See author list of the BEAR paper on Human impacts (above)