In the March 9. 2023, issue of Nature, an international team of researchers, including GEOG Assistant Professor Xiao-Peng Song, published a cover article on algal bloom distribution and trends in global coastal waters.

Phytoplankton blooms are accumulations of microscopic algae in the surface layer of fresh and marine waters. Many algal blooms are beneficial, fixing carbon and supporting fisheries and ecosystems, but proliferations of algae can also cause harm to the environment, such as releasing toxins or depleting oxygen.

The researchers analyzed 0.76 million MODIS images onboard NASA’s Aqua satellite and presented a comprehensive map of bloom distribution and trends in coastal ecosystems between 2003 and 2020. Algal blooms were found in 126 out of the 153 coastal countries examined.

The spatial extent and frequency of blooms increased significantly over the study period. The satellite-observed bloom expansion and intensification were driven by several factors including changing ocean circulations, rising sea-surface temperatures, and anthropogenic nutrient enrichment related to agricultural activities on land. 

Read the open access article here.