Algae report number 7, 2015

Type: Report
Author: Marie Johansen


This report covers the Baltic Proper only as this expedition is reporting from the Finish cruise. All analyses have been performed onboard the ship and the main focus was to follow the cyanobacterial surface accumulations and blooms.

Summary of surface accumulations
The warm air temperature and the light winds which occurred in the beginning of the week promoted small and larger aggregations of cyanobacteria throughout the area visited. A large area of small aggregations of filamentous cyanobacteria was found at the entrance to the Gulf of Finland and aggregations persisted more or less constant along the eastern parts of the Baltic Sea, east of Gotland. The filamentous cyanobacteria Aphanizomenon flos-aquae and Nodularia spumigena were found in large quantities in the northeastern Baltic all the way down to the south of Gotland. South of Gotland the concentrations dropped temporarily and then rose again. Large surface accumulations were noted in the waters between Öland and Gotland. Cyanobacterial grains in high densities were found throughout the upper water col-um. North of Gotland, above the Landsort Deep, surface aggregates were found and also large areas with grains in between the surface aggregates.

Please follow the link below to see interpretations of blooms from satellite images in the Baltic