Massive Seaweed Belt Approaching Florida's Coastline.

A 5,000-mile seaweed belt known as the Great Atlantic Sargassum Belt is expected to wash onto beaches in the Caribbean Sea, South Florida, and the Yucatán Peninsula in Mexico. Sargassum is a brown algae that carpets beaches, releasing a pungent smell as it decays and entangling humans and animals who step into it. The seaweed originates in the Sargasso Sea and provides breeding ground, food, and habitat for fish, sea turtles, and marine birds. Scientists estimate there’s more than 10 million metric tons of sargassum in the belt this year, caused by agricultural runoff, warming waters, and changes in wind patterns, sea currents, rainfall, and drought.