Algblomning sedd från ovan.
Övergödning och klimatförändringar har ökat algblomningarna längs Sveriges kuster.
Photo: Copernicus Sentinel-1

Help scientists map algal blooms in the ocean


Researchers at the University of Gothenburg want help from the public to report algal blooms along the Swedish coast. The goal is to develop a digital service that can predict where and when toxic algal blooms will occur.

Every summer there are reports of algal blooms in the sea that plague the lives of bathers, boaters and fishermen. In recent years, reports have become increasingly frequent.

– Climate change means that we unfortunately expect more and larger algae blooms in the future, says Ana Tronholm, researcher in marine biology at the University of Gothenburg.

Ana Tronholm portrait
na Tronholm, researcher at the Department of Biology and Environmental Science.
Photo: Niclas Engene

In the new research project Algal Blooms Sweden, Ana Tronholm requests reports from private individuals who discover algal blooms along the Swedish coast. The reports are submitted by filling in a simple form on the phone where the observation date, location, color and photos are entered.

The reports are then combined with data from measurement series from the Swedish Meteorological and Hydrological Institute and satellite monitoring.

– The goal is to use artificial intelligence to develop an app or a digital service that everyone can use to predict where and when algal blooms will occur, says Ana Tronholm.

Toxic algal blooms

Algae blooms are the mass presence of microscopic algae and cyanobacteria that occur mainly in spring and summer when nutrients are available and water temperatures rise. Some cyanobacteria produce toxic substances (secondary metabolites) that can be harmful to the environment and human health.

Part of Ana Tronholm's research is about finding out which toxins the cyanobacteria in the Baltic Sea produce and investigating how environmental factors regulate the production of these toxins at the molecular level in relation to eutrophication and climate change.

– The levels of toxins produced can depend on several parameters. These include temperature, salinity, pH and how the supply of nutrients is in the water. The species in question is also important, says Ana Tronholm.

Marine Citizen Science 

This project is part of the University of Gothenburg's investment in Marine Citizen Science. Algal Blooms Sweden collaborates with the Information Center for the Baltic Proper at the County Administrative Board in Stockholm County, which has long been collecting data by receiving reports on algal blooms. But with modern technology, the information can be used to develop a service that can benefit many.

– I hope that many want to help report algal blooms. The more data we get, the better predictions we make, says Ana Tronholm.

Text: Karl-Johan Nylén

Report algal blooms

Go to this page to report algal blooms in the Baltic Proper (from the Åland Sea to the Danish Strait) and to this page for blooms outside that area. Enter your phone number.

Information is sent to a database that collects the reports. No personal data is stored.