Summary
Surface water temperatures were normal in the Skagerrak, while it was above normal in the Kattegat and Baltic Proper. Nutrient levels in surface water were normal throughout the investigated area. In the main part of the Baltic Proper oxygen concentrations below 2 ml/l were observed at depths exceeding 70 to 80 meters. Hydrogen sulphide was found, in the Western Gotland Basin, deeper than 70-80 meters. In the Eastern Gotland Basin hydrogen sulphide began at depths between 125 and 150 meters. Blooms of cyanobacteria in the surface layer took place in the Baltic Proper but in the Skagerrak and Kattegat a typical summer situation with low cell numbers and few species of phytoplankton prevailed. Surface accumulations of cyanobacteria, (blue-green algae) were observed in the southern parts of the Baltic Sea and the eastern Gotland Basin. A more detailed report on the algae situation can be found at: http://www.smhi.se/oceanografi/oce_info_data/reports/havmiljoarkiv/oce_reportarcive10.html