Good news, Florida; the giant seaweed blob has shrunk

FLORIDA – For months, Florida’s usually picturesque coast was plagued by

a rotting tangle of seaweed, known as sargassum.

Then, as quickly as the stinking mass arrived, it began to disappear.

Beachgoers rejoiced, posting pictures of white sands and sparkling waters on social media.

Scientists said they had expected the sargassum in the Gulf of Mexico to wane eventually – but not so fast, or by so much.

“That is a surprise,” said Professor Chuanmin Hu, a professor of oceanography at the University of South Florida, noting that there was still “a lot of sargassum” in the tropical Atlantic.

“The good news is the sargassum season for Florida is very likely over for this year. But for the Eastern Caribbean, it’s not over yet,” he said.

In June, the amount of sargassum in the Gulf of Mexico dropped by a staggering 75 per cent, Prof Hu and colleagues at the University of South Florida Optical Oceanography Lab noted in a bulletin published last week.

Sargassum – a type of macroalgae that is naturally abundant in the Sargasso Sea – has long been seen floating in mats across the North Atlantic.

But in 2011, scientists began to observe extraordinary accumulations of the seaweed extending in a belt from West Africa to the Caribbean Sea and Gulf of Mexico, according to a 2019 study.

The immense bloom has continued to grow almost every year.

In March, scientists said they expected the blob to come ashore in Florida and elsewhere along the Gulf of Mexico.

At sea, the blob provides habitat for fish, crabs and sea turtles, but on land, it began to rot, emitting toxic fumes and fouling the region’s beaches over the busiest summer months.

Like other plants, sargassum has a natural life cycle, Prof Hu said, and scientists expected it to decrease in the Gulf of Mexico by around September.

But scientists do not know why the decline was so rapid.

One theory is that strong winds caused by recent tropical storms could have dissipated the sargassum into smaller clumps or sunk it to the ocean floor, Prof Hu said, making it hard to see from a satellite.

“There could be other reasons; we just don’t know,” he added. NYTIMES