The massive algal bloom headed for Florida is a mystery to scientists

Five thousand miles long, 400 miles wide and over six million tons, a massive algal bloom is drifting toward Florida and the Gulf of Mexico.

Scientists at the University of South Florida, with help from the National Aeronautics and Space Administration, are monitoring blooms of sargassum, a type of brown algae, using satellites. Originating in the Atlantic Ocean, the bloom is approaching the Caribbean Sea and Gulf of Mexico, posing a threat to beaches throughout the Gulf, including the tourist hotspot of Florida.

“If you’ve ever been on a beach that had a huge abundance of it, it’s not fun,” Dave Tomasco, executive director of the Sarasota Bay Estuary Program, told ABC News. “It’s rotting, depleting the water of oxygen and smelling like rotten eggs.”

When the bloom hits a beach, it can pile up one to two meters high on the shoreline and block swimmable waterways, scientists said. If the seaweed is not removed quickly from the beach, it will begin to rot, releasing hydrogen sulfide gas, more closely related to the smell of rotten eggs that can irritate the skin, eyes and throat, as well as make it difficult for people to breathe with asthma.

According to Tomasco, the bloom is more likely to hurt the tourism industry than it is to harm wildlife by piling up and fouling famous Florida beaches.

Octavio Penaloza, who runs Wings Beachwear in Miami Beach, said the bloom affecting Miami could affect his bottom line.

“If something happens on the beach, it will affect us,” he said.

He noted that its busy season includes June and July – the same months that sargassum peak in size, according to scientists. While his customer base includes tourists who buy souvenirs without visiting the beach, many customers pass by his shop for beachwear, which would be unnecessary if the beaches become less pleasant.

“[If] the algae comes, we’re going to have like less people coming to buy from our store because they’re mostly buying things to go to the beach,” Penaloza said.

For a measurable impact on Florida’s beaches, University of South Florida research professor Brian Barnes said a concentrated amount of algae about “the size of a football field” needs to land on a shore immediately.

“If it’s a big enough balloon or a big enough piece that hits a certain beach, then it can overwhelm the possibilities [of the beach]Barnes said.

While six million blooms span more than two million square miles, it fully covers only about 0.1 percent of the sea’s surface, spread out in patches that vary greatly in size, according to Barnes. The bloom will take months to finally reach land and may increase in size as the water temperature rises. Where it makes landfall also depends on wind and currents, with Barnes warning that Southeast Florida, including Miami and the Florida Keys, are the areas in the United States most likely to be affected.

Whenever it arrives, the Florida Department of Health warns that decaying sargassum hydrogen sulfide will irritate the skin, eyes, throat and nose. It is unlikely to be seriously injured in an airy environment such as a beach, but people with asthma may have difficulty breathing due to the gas.

Tomasco also noted that hydrogen sulfide could interact with paint molecules in homes, turning them grayish silver and even tarnishing silverware.

Chuanmin Hu, a professor at the University of South Florida who is working to monitor the bloom with Barnes, said the amount of algae heading ashore is not cause for alarm, stressing that sargassum is natural and not toxic to marine life. oceans.

Hu said this amount of algae is the “new normal” for the Atlantic Ocean. However, the current kelp mass set the record for the largest sargassum bloom recorded in January, although it decreased in size in February.

“At least it will be one of the major sargassum years, although we don’t know if it will be a record year or not,” Hu said, noting that the size of the bloom peaks in June and July.

Compared to red tide, a toxic algal bloom that has wreaked havoc on Florida’s Gulf Coast for the past decade killing marine life, even manatees, sargassum is not harmful to wildlife in most circumstances. Hu said some animals, including sea turtles, fish, crabs and shrimp could eat or take shelter in the blooms.

However, Tomasco warned that sargassum on beaches could disrupt sea turtle nesting habitats. Hu also noted that if sargassum sinks to the ocean floor solidly, it could suffocate and kill corals and seagrasses.

“They sink to the bottom of the ocean and drown things out,” Hu said, noting that most of the bloom will likely end up on the sea floor instead of on the beach.

While the blooms are the “new normal” compared to recent years, Barnes noted they were “unheard of” before 2011, calling their sudden appearance a mystery.

“Any type of bloom of any relative magnitude is unheard of before 2011,” Barnes said. “Like, we’ve never seen any kind of bloom like this. There are no reports of huge beaches or anything like that in the Caribbean.”

While Hu said there is no direct evidence linking the blooms to climate change, Tomasco pointed to the nature of sargassum — including the fact that it grows in warmer waters — as a clue as to why it has reappeared.

“The world is changing, and part of that is the oceans are warming, and algae seems to be able to grow over a longer period of the calendar now than it used to,” Tomasco said.

Tomasco also pointed to Florida’s increased use of fertilizers in agriculture and landscaping, which runs into the bay and helps stimulate algae growth. Hu clarified that the fertilizer will affect the algae when it enters the Gulf of Mexico near the coast, not when the sargassum initially grows in the Atlantic.

Regardless of the reason for the growth, what is clear to all three scientists is that coastal communities will learn to manage this alga’s new normal.

“I don’t see anything that shows it’s trending anywhere but up,” Barnes said.