The Baltic Sea has been under pressure for decades: Although phosphorus and nitrogen river loads, the main cause for its eutrophication, have been significantly reduced, adverse effects such as algal blooms and oxygen depletion still massively occur, leading to further ecological problems. Scientists at the Leibniz Institute for Baltic Sea Research Warnemünde (IOW) have now published a comprehensive review showing how nutrient pollution, internal matter cycles and global warming interact, thereby delaying the impact of protective measures. They also identify potential approaches for effective Baltic Sea management. The study was recently published in the Annual Review of Marine Science.