News

16. February 2026

Long-term monitoring of nutrient concentrations in the Baltic Sea: An analysis of data on phosphate and nitrate concentrations in the central Baltic Sea, collected since the 1960s and 1970s, reveals the complex interrelationships between nutrient cycles and the hydrographic conditions of the Baltic Sea. The analyses focus on phosphate and examine the influence of saltwater inflows from the North Sea, as well as nutrient loads from catchment areas and the atmosphere, on the nutrient balance of surface and deep water.

Joachim Kuss, Peter Holtermann, Lars Umlauf, Olaf Dellwig, Ralf D. Prien, Joanna J. Waniek (2026). The Changing Baltic Sea: Between Nutrient Load Reduction and a Warming Climate. Annu. Rev. Mar. Sci. 2026. 18:16.1–16.26, doi.org/10.1146/annurev-marine-040324-020707

06. February 2026

Sea levels of the Baltic Sea at an all-time low: Since the beginning of January, an unusually prolonged period of easterly winds has caused the average sea level of the Baltic Sea to fall to a historic minimum. Measurements at the Swedish gauge at Landsort-Norra show levels lower than at any time since records began in 1886. This may create a rare oceanographic condition conducive to a large influx of salt water from the North Sea into the Baltic Sea. Such an inflow could significantly alter the physical and chemical conditions in the deep basins of the central Baltic Sea.