Scientists have used NASA satellite observations to discover what they say is the largest bloom of macroalgae in the world.
Called the Great Atlantic Sargassum Belt, it forms its shape in response to ocean currents, based on numerical simulations. It can grow so large that it blankets the surface of the tropical Atlantic Ocean from the west coast of Africa to the Gulf of Mexico.
This happened last year when more than 20 million tonnes of it caused problems on shorelines lining the tropical Atlantic, Caribbean Sea, Gulf of Mexico, and east coast of Florida.
Writing in the journal Science, a team led by the USF College of Marine Science reports that environmental and field suggest the belt forms seasonally in response to two key nutrient inputs: one human-derived, and one natural.
“The evidence for nutrient enrichment is preliminary and based on limited field data and other environmental data, and we need more research to confirm this hypothesis,” says USF’s Chuanmin Hu.
“On the other hand, based on the last 20 years of data, I can say that the belt is very likely to be a new normal.”