A University of South Florida researcher thinks he has figured out why there鈥檚 so much brown, moss-like algae that causes that rotten egg smell on the Caribbean Sea and Gulf Coast beaches.
Biological oceanographer Frank Muller-Karger is a professor at the USF College of Marine Science.
Muller-Karger and a team of researchers analyzed currents, winds and nutrient levels to determine that vertical currents are behind the massive blooms creating the .
The study, published in , explains that vertical currents are sweeping deep-ocean nutrients up toward the sunlit surface.
READ MORE: A major sargassum season could be in store for Florida
"The nutrients are mixed up from deeper water. There's plenty of light and these plants photosynthesize, so they just grow,鈥� Muller-Karger said. 鈥淭hey grow like crazy."
These conditions have occurred annually since 2011.
Muller-Karger said his research could help prevent erroneous information that could lead to an 鈥渋nternational incident.鈥� Prior to this study, some researchers had blamed Amazonian deforestation for the sargassum blooms.
When the macroalgae washes onto the beaches, it rots, releasing hydrogen sulfide and a rotten egg smell. While sargassum itself is to humans, it does carry tiny sea creatures whose sting can create rashes and blisters.
While it may be a nuisance to fishermen and beachgoers, Muller-Karger said the algae supports ocean life.
"We think this is the new normal compared to what it was before,鈥� he said.
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