On the West Coast as well as in the Arkona Basin, all nutrients were almost depleted. A strong bloom was ongoing in the Hanö Bight and in the Bornholm Basin. In the remaining parts of the Baltic Proper winter conditions prevailed. The deep water in the Arkona and Bornholm Basins as well as in the Hanö Bight were well oxygenated. A thin layer of oxygenated water (0.2 ml/l) was found at the bottom at BY15. Hydrogen sulphide was otherwise present in the Eastern and Western Gotland Basins at depths exceeding 100 to 125 metres.