Blue-green algae blooms decrease in sea, lakes

The amount of blue-green algae in sea areas and lakes has clearly decreased this week, said the Finnish Environment Institute (SYKE) in a press release on Thursday.

Inland waters and coastal areas no longer have any observations of very abundant blue-green algae blooms.

Blue-green algae, however, may still occur later in the autumn as the weather cools, but the blooms are usually not as strong as in summer.

The monitoring of the this year´s blue-green algae situation ended on Thursday.

SYKE reports on the national cyanobacterial situation on a weekly basis every Thursday from the beginning of June until the end of August. The weekly algal reporting was launched in 1998.

SYKE observes the cyanobacteria occurrence as part of the monitoring of the state of the environment in Finland

The national cyanobacterial monitoring is carried out as part of the monitoring of the state of the environment in cooperation with the Centres for Economic Development, Transport and the Environment, municipal environmental and health authorities, and the SYKE.

Finnish Rotary Clubs are also actively involved in nationwide cyanobacterial monitoring.

The cyanobacterial monitoring is based on the monitoring of cyanobacterial deposits in surface water. The intention is to provide an overview of the cyanobacterial situation in different water bodies.

The monitoring includes about 400 permanent observation sites across the country on inland and coastal waters and in the archipelago.

Information on the cyanobacterial situation in the open sea areas is mainly obtained from satellite images, but also from the Finnish Border Guard, the marine research vessel Aranda, the optical device located at the Utö Atmospheric and Marine Research Station, as well as cruise and merchant ships (MS Finnmaid and MS Silja Serenade) equipped with Algline measuring equipment. The drift forecasts for cyanobacterial rafts in open sea areas are prepared in cooperation with the Finnish Meteorological Institute's Maritime Services.