Surface water temperatures were below normal in all investigated areas. Nutrients in the surface layer were almost completely consumed in the Skagerrak and Kattegat and the spring bloom was in progress. In the Baltic Proper winter conditions still prevailed and nutrient concentrations were above mean for the season, especially in the southern parts. The bottom water in the Arkona Basin was well oxygenated. Oxygen concentrations below 2 ml/l were found at depths exceeding 80 to 90 metres in the main part of the area. Hydrogen sulphide was measured in the Eastern and Western Gotland Basins from a depth of 125 metres.