Baltic Sea overheating: beaches closed as cyanobacteria blooms return

The first Baltic Sea bathing areas have been closed in 2026 due to cyanobacteria blooms. Scientists say that warming water temperatures and persistent eutrophication are making blooms increasingly frequent. Marcin Kotlarek, head of the Race for the Baltic Foundation, confirmed that the problem will worsen, as warm, nutrient-rich water provides ideal conditions for cyanobacteria growth.