Cruise report from R/V Aranda week 36, 2014

Type: Report
Author: Martin Hansson


The water temperature in the surface layer was above normal in Skagerrak and the Baltic Proper. The thermocline in Skagerrak was found at 75-100 meters which is significantly deeper than normal. Nutrients in the surface layer showed normal concentrations except for silicate that in the Western and Eastern Gotland Basin was elevated.

The western parts of the Arkona Basin were oxygenated while the eastern parts suffered from acute hypoxia from depth exceeding 35 meters. Oxygen conditions in the Eastern Gotland Basin had deteriorated in the central parts where anoxia was found from 125 meters and acute hypoxia from 80 meters depth. Though, in the southern parts of the Eastern Gotland Basin oxygenated bottom water was registered which indicate that a pulse of new bottom water had reached the basin. In the Western Gotland Basin anoxic condition was found from 75 meters and anoxia from 55-65 meters. Also at Släggö on the west coast of Sweden, acute hypoxia was found in the bottom water.