Cruise report from R/V Argos week 20, 2013

Type: Report
Author: Bengt Yhlen, Philip Axe


Phosphate concentrations in the south and western Baltic Proper remain much higher than normal. Silicate measurements also showed high levels, while nitrate levels were normal. Nutrient concentrations in the Skagerrak and Kattegat were normal. In the Baltic Proper oxygen concentrations below 2 ml/l were found at depths exceeding 70 to 90 metres. Hydrogen sulphide was found in the bottom water in the Hanö Bight and the Bornholm Basin, and in a roughly 20 metre deep layer over the bottom around Gotland from about 110 metres. The CTD-curve revealed a relatively high peak on the chlorophyll measurements at Anholt at about 15 meters depth. Other than this there were no high peaks in Skagerrak, Kattegat, Sound or Baltic Proper. The potentially toxic dinoflagellate Dinophysis acuta was observed at Gotlandsjupet, Hanö Bight and BCSIII. The latter also showed some cyanobacteria in the form of Aphanizomenon sp.