Mapping was performed in the Baltic. The weather was mostly cloudy and hazy. Moderate to strong winds from the west dominated. The surface water temperatures were normal for the season in the whole area i.e. about 5°C in the Skagerak, 3°C in the Kattegat and between 2 and 4°C in the Baltic. The spring bloom in the Kattegat continued; both inorganic nitrogen and silica were depleted and the phosphate concentration was low. In the Baltic no production occured and typical winter concentrations of the nutrients were measured. The oxygen concentrations in the Baltic were below 2 ml/l from about 80 m depth in the Gotland Basin and about 70 m in the Bornholm Basin. No hydrogen sulphide was detected in the Baltic Sea.