In the Southern Baltic Proper, concentrations of phosphate and silicate in surface waters remain high, while nitrate concentrations were normal. Nutrient concentrations in the Skagerrak and the Kattegat were normal for the season throughout the study area. There was an algal bloom along the Swedish west coast as well as in the central Skagerrak. In the Baltic no algal activity could be seen. In the Baltic Proper oxygen concentrations were below 2 ml/l at depths exceeding 70 to 80 metres. Hydrogen sulphide was found in the eastern Gotland Basin deeper than 145 metres, and in the western Gotland Basin deeper than 90 metres.