Scientists puzzled by massive seaweed bloom heading towards Florida beaches.

A massive bloom of sargassum seaweed, spanning 5,000 miles long, 400 miles wide, and over six million tons, is drifting towards Florida and the Gulf of Mexico, posing a threat to beaches and tourism. The bloom can pile up to two meters high on the shoreline, clog swimmable waterways, and emit hydrogen sulfide gas, which can irritate skin, eyes, and the throat. While sargassum is not toxic to ocean life, it could disrupt sea turtle nesting habitats and smother coral and seagrass. The sudden emergence of the blooms since 2011 is a mystery to scientists, but warmer waters and increased use of fertilizers in Florida agriculture and landscaping are possible factors.