Expeditionsrapport från U/F Argos vecka 49-50, 2003

Typ: Rapport
Författare: Bodil Thorstensson, Philip Axe


Surface phosphate levels in the southeastern Baltic Proper, East Gotland Basin and Northern Baltic Proper were 1-2 standard deviations above the 1990-1999 average. This is possibly related to the re-oxygenation of the deep water the previous winter and spring, and the release of phosphate from the bottom sediment. This is likely to impact on primary productivity next spring. Silicate levels remain above average throughout the Baltic Proper. Oxygen concentrations below 2 ml/l were found in the Eastern, Western and Northern Gotland Basins at depths exceeding 60 to 80 metres. Hydrogen sulphide was found from 80-90 metres in the Western Gotland Basin and from 90 metres in the Northern Gotland Basin. Despite the low oxygen concentrations east of Gotland, these values are better than the average 1990-1999 conditions. High surface salinity at Drogden East and West Landskrona, with a northward current, suggest that a saline inflow to the Baltic had just finished.