Summary
Surface phosphate concentration was above normal in Kattegat, the Sound and in the western and southern part of the Baltic. In the Arkona Basin. the water below the halocline was well oxygenated with levels round 4 ml/l. In the rest of the Baltic Proper oxygen concentrations below 2 ml/l were observed at depths exceeding 60 to 70 metres. In the West Gotland Basin and Northern Baltic Proper, hydrogen sulphide was found below 70-90 metres. In the East Gotland Basin hydrogen sulphide began at depths between 100 and 140 metres. Phytoplankton activity was relatively low in the area.