Future projections of record-breaking sea surface temperature and cyanobacteria bloom events in the Baltic Sea

Authors: H. E. Markus Meier, Christian Dieterich, Kari Eilola, Matthias Gröger, Anders Höglund, Hagen Radtke, Sofia Saraiva and Iréne Wåhlström.

Type of publication: Article peer review

Aiming to inform both marine management and the public, coupled environmental-climate scenario simulations for the future Baltic Sea are analyzed. The projections are performed under two greenhouse gas concentration scenarios (medium and high-end) and three nutrient load scenarios spanning the range of plausible socio-economic pathways. Assuming an optimistic scenario with perfect implementation of the Baltic Sea Action Plan (BSAP), the projections suggest that the achievement of Good Environmental Status will take at least a few more decades. However, for the perception of the attractiveness of beach recreational sites, extreme events such as tropical nights, record-breaking sea surface temperature (SST), and cyanobacteria blooms may be more important than mean ecosystem indicators. Our projections suggest that the incidence of record-breaking summer SSTs will increase significantly. Under the BSAP, record-breaking cyanobacteria blooms will no longer occur in the future, but may reappear at the end of the century in a business-as-usual nutrient load scenario.

Meier, H.E.M., Dieterich, C., Eilola, K. et al. Ambio (2019) 48: 1362.
DOI 10.1007/s13280-019-01235-5