South Florida's Optical Oceanography

Huge blankets of seaweed are smothering coastlines from the Caribbean to Mexico

Huge blankets of seaweed called sargassum are covering beaches from the Caribbean to Mexico. In July, scientists measured about 27 million metric tons of this seaweed in the Atlantic, Caribbean and Gulf of Mexico. The data comes from a report by the University of South Florida's Optical Oceanography Lab. The seaweed can block sunlight, harm marine life and make beaches less attractive for visitors.