Algal blooms known as "red tides" not only kill fish but also harm human health. Inhaling the toxins released by the microorganisms can cause respiratory irritation and, according to the Roscamp Institute, also brain fog, worsened migraines and cognitive fatigue. However, the public still has a poor understanding of exactly when these risks peak.
Researchers at Florida State University led by Bingqing Liu, a specialist in satellite oceanography, are studying how extreme weather events affect toxic algae. In 2024, Hurricane Milton caused a rapid intensification of a bloom of Karenia brevis, the organism responsible for red tides in Florida. The work was published in the journal Scientific Reports.
According to the study, heavy rains and runoff from land carry large amounts of pollutants into coastal waters, creating a nutrient environment for the growth of toxic algae. Thus, hurricanes can indirectly increase the health risk for people living along the coast.
Hyperspectral satellites are becoming an important monitoring tool: they take images in hundreds of narrow spectral bands, which makes it possible to distinguish types of algae, not just their total mass. For the first time, data from NASA's PACE satellite made it possible to map and distinguish Karenia brevis from other groups of phytoplankton in coastal waters.
"New hyperspectral missions such as PACE provide much more detailed information about ocean color, allowing us to distinguish types of phytoplankton, not just total abundance, including harmful species such as Karenia brevis," Liu says. "This makes it possible to detect bloom development earlier and more accurately over large areas. Combined with forecasting tools, such observations can provide warning of potential exposure so that vulnerable people, for example those prone to respiratory or neurological symptoms, can take action before conditions worsen."
According to the researcher, artificial intelligence helps move from simple observation to prediction. Algorithms analyze satellite images, ocean models and environmental data - temperature, salinity, currents and nutrient levels - and identify patterns that precede red tides. This makes it possible to detect blooms earlier and provide short-term forecasts. "We cannot prevent a red tide, but we can significantly improve early warning and reduce its impact on communities and ecosystems," Liu notes.
Red tide toxins - brevetoxins - can become airborne when wave action breaks up algal cells and be inhaled, causing respiratory irritation and potentially neurological symptoms such as headaches or brain fog. In addition, they accumulate in shellfish, creating a risk when eaten. Understanding how a bloom develops, intensifies and moves is critically important for forecasting exposure pathways and protecting public health.
The study emphasizes that new satellite technologies and AI could form the basis of an early warning system, but further work will be required to implement it. For now, the focus is on correlations and models, not on a proven reduction in illness.