Summary
Surface water temperatures were normal, except in the southern Skagerrak, Kattegat and the Sound, where the temperature was some degrees higher than normal. The concentrations of phosphate and silicate in the southern Skagerrak were higher than normal. High ammonia values were found there as well. In the Arkona and Bornholm Basins, phosphate- and silicate concentrations in the surface water remained high. In the Sound concentrations of phosphate and silicate were lower than normal. Oxygen concentrations below 2 ml/l were observed in the bottom water at depths exceeding 60 to 70 metres in southern Baltic and in the Karlsö Deep, exceeding 90 metres in the northern part and 80 metres in the eastern Baltic Proper. Hydrogen sulphide was found below 80 metres in the Bornholm Basin, from 60 metres in the Hanö Bight, from 80 to 90 metres in the western Gotland Basin, and from 100 to 150 metres in the eastern and northern Gotland Basin.