Cruise report from R/V Aranda week 29-30, 2016

Type: Report
Author: Martin Hansson


The cruise was part of the Swedish regular marine monitoring programme covering the Skagerrak, the Kattegat, the Sound, the Gulf of Finland and the Baltic Proper. This report is based on data that have only undergone a first quality control, when data is published at the data host some values might have changed after further quality controls have been performed. Due to a period of sunny and calm weather the surface temperature was over normal in several of the investigated areas. The nutrient concentrations of phosphate and nitrogen were low or totally consumed in the surface water. The silicate concentration was still higher than normal in some parts of the Baltic Proper. Anoxic areas were found in the Western Gotland Basin and in the Gulf of Finland from depth exceeding 90 meters. In the northern parts of the Eastern Gotland Basin the near bottom areas were still anoxic and hydrogen sulphide was now again present near the bottom at BY15, in the central parts of the basin. Acute hypoxia (< 2ml/l oxygen) was found at depth over 70 meters in the whole Baltic Proper. Surface accumulations of cyanobacteria were found in large areas of the Baltic Proper. A summary of the algae situation can be found in this report.

Next regular cruise is scheduled to start 22th of August.