Cyanobacteria, also known as blue-green algae, are a group of microorganisms that live in aquatic environments throughout the world. Some types of cyanobacteria are known to produce a variety of toxins that may cause harm and sometimes death to fish, wildlife, domestic animal, and rarely, humans.

Several studies have indicated that cyanobacterial harmful algal blooms (cyanoHABs) have increased in frequency, extent, and magnitude, globally over the last several decades. However, data are not available to quantify these metrics at regular intervals and across wide geographic scales. The lack of this information poses future risk to the environment and public health.

To inform monitoring priorities and management decisions, timely assessment methods are needed for regions experiencing cyanoHABs, as well as those where blooms are likely to occur in the future. To that end, a recently published paper (2022) by Schaeffer et al., quantified the spatial extent of cyanoHABs using satellites from the European Space Agency (ESA).