Harmful algal blooms, or “HABs”, are proliferations of phytoplankton species that can produce toxins hazardous to human and ecosystem health, or in other ways harm marine organisms or disturb the marine environment. HABs include microalgae such as Nodularia, capable of producing the neurotoxin nodularin, Pseudochatonella (the “fish killer”) that can physically harm the breathing apparatus of marine organisms, or so-called “nuisance blooms” consisting of for example Aphanizomenon, that not only can produce anatoxins but also can make beaches unattractive or aquatic sports dangerous. Every year HABs have severe detrimental effects across the globe on aquaculture and the tourism sector. For example, in 2019, a single HAB-forming species killed millions of aquaculture salmon in Norway, corresponding to 40,000 metric tons of salmon and costing the industry well over 200 million Euros.

Despite the fact that HABs are well-known across our oceans and are increasing at an alarming rate, their dynamics and responses to form blooms under certain environmental conditions remain poorly understood. Today scientists have developed two main methods to monitor HABs: (1) analysis of satellite images where specific ocean colour corresponding to pigments such as chlorophyll-a is translated to bloom intensity, and (2) in-situ sampling of chlorophyll-a as a proxy for bloom intensity, taxonomic identification by microscopy to detect toxic species and measurements of toxins to confirm toxicity. Further, scientists have determined that HABs typically bloom under conditions with (1) high concentrations of nutrients (mainly nitrogen and phosphorus compounds; NO2, NO3, NH4, PO4), (2) high light intensity and temperature (except for blooms of diatoms and dinoflagellates in the spring that can bloom at colder temperatures), and (3) stable weather without wind and waves where the blooms can surface. However, beyond this, scientists across the globe are still trying to answer how to predict HAB blooming.

For its third innovation challenge, ODF Sweden has developed the following challenge: To develop an AI-based prognosis tool to predict where, when and how HABs will form in the context of aquaculture and tourism. The AI tool should predict HABs both short-term (days to weeks) and long-term (years to decades), given the climate change projections for Swedish waters. We are working with two case studies to develop HABs prognosis models on a subset of data and specific species of microalgae in: (1) the aquaculture industry on the Swedish west coast (the Skagerrak Sea) and (2) the tourism sector in the Baltic Sea. Extensive ocean data for these essential variables, such as those above, can also be found in databases open to the public.

By targeting a more general project aim and by looking into specific case studies, ODF Sweden is answering the needs from several different end users and stakeholders. These include the Swedish Food Agency, the Swedish Agricultural Board, local mussel farmers and the tourism sector. ODF Sweden is already in contact with these stakeholders and end users, and together we are forming a network to specify the exact needs for a HABs prognosis tool. The work in this project will cover the whole chain from research and development to product innovation and marine management through the use of ocean data in the digital blue economy.

The Killer Algae Challenge is currently ongoing. If you are interested in learning more or contributing to this challenge, please contact us at email@oceandatafactory.se.