A seaweed blob twice the width of the US is heading toward Florida. Here's what you should know

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A huge blob of seaweed nearly twice the size of the United States is heading for Florida and other Gulf of Mexico coastlines. It threatens to litter beaches with noxious and potentially harmful piles and will dampen tourism season.

Sargassum, a specific type of seaweed, has been forming large blooms in Atlantic Ocean since 2011 and scientists have been monitoring massive accumulations ever since. This year's bloom may be the largest, spanning over 5,000 miles (8.047 kilometers) between the coasts of Africa and the Gulf of Mexico.

According to Dr. Brian Lapointe of Florida Atlantic University's Harbor Branch Oceanographic Institute, this year's sargassum flower began early and doubled in size from December to January. According to Dr. Brian Lapointe, the mass was larger than ever since 2011's new region of sargassum development.

The blob will travel west and push through the Caribbean to reach the Gulf of Mexico in the summer. Lapointe stated that the seaweed will likely be found on Florida beaches around July.

Lapointe stated that this is an entirely new phenomenon in oceanography, which is causing a huge problem for tourism in the Caribbean, where it accumulates on beaches up to 6 feet deep.

Here are some facts about these mass movements and their impact on humans and the ocean.

What is Sargassum?

Sargassum can be used as a generic term to describe more than 300 species brown algae. However, Sargassum natans or Sargassum fluitans are most common in the Atlantic.

Algae can be found drifting at sea and have many benefits for ocean life.

According to the Sargassum Info Hub, which is a collaboration of several research institutions, "This floating habitat provides food for fishes and mammals, marine birds and crabs, as well as protection," It is a vital habitat for endangered loggerhead sea turtles.

Are sargassums safe?

Sargassum can cause problems when it lands on beaches. It can pile up in large mounds, making it difficult to navigate, and can emit a gas that smells like rotten eggs.

Sargassum can quickly become a threat to the ocean, and it can be an asset.

It can be found in large quantities, which basically suckers oxygen from the water and creates what Lapointe calls dead zones. These are nursery habitats for fisheries... once they're devoid, it's gone.

Lapointe also stated that Sargassum can pose a danger to human health. Hydrogen sulfide, a gas produced by rotting algae, is toxic and can cause breathing problems. Arsenic is also found in seaweed, which can be dangerous if it is eaten or used as fertilizer.

Lapointe stated, "You must be very careful when cleaning the beaches."

What is the problem with sargassum?

Like plants and crops, seaweed's growth can change year to year, according to Dr. Gustavo Jorge Goni of the National Oceanic and Atmospheric Administration's Atlantic Oceanographic and Meteorological Laboratory.

Goni said that the sea currents also have an impact on sargassum growth and accumulation. The sea may provide nutrients for the algae, such as phosphate and nitrogen.

These elements can be dumped in the ocean by rivers that have accumulated phosphorus or nitrogen through human activities like agriculture and fossil fuel production according to the US Environmental Protection Agency.

Goni stated that researchers are currently looking at ways to reduce the impact of seaweed on beaches. This could be done by either sinking the seaweed to the bottom or harvesting the seaweed for commercial use, but this is not the current focus.

Goni warned that the research on these sargassum accumulations was new and that scientists' understanding of how algae grows will likely change over time.

He said that whatever we think we know today may be wrong tomorrow.

What does this mean for travel?

Lapointe advised that you research the possibility of sargassum being present in your destination before traveling to the coast this summer or spring. Make sure you plan ahead to ensure your vacation is memorable.

Lapointe stated that there are several sargassum Facebook pages, where members post about what they saw on beaches.

He stated that the recession had already affected the travel industry.

Lapointe stated that sargassum can buildup overnight and you may not be able predict its effects during a trip.

"This is why they're trying to develop these early warning systems -- high-resolution in coastal areas, that takes higher-resolution satellite imaging to better show what's actually coming into beaches within the next 24 hours or 48 hours," he said.

Satellite images taken within the past week have shown that sargassum doesn't appear to be an amorphous mass moving across oceans, but teardrop-shaped blobs that are trailed by thin, long strands seaweed.

In the past week, sargassums were spotted at 215 miles (346 km) from Guadeloupe. They are located between the islands St. Vincent and Bequia, 1000 yards (914m) off Martinique, and the coast of Key Largo in Florida.

How can sargassum be cleaned up?

According to the Sargassum Info Hub, algae that has accumulated on beaches can cost millions to remove and could also cause harm to marine life.

Lapointe stated that Barbados had 1,600 dump trucks per day for cleaning the beaches of the seaweed in order to make them suitable for tourists and recreational use.

According to the Dutch Caribbean Nature Alliance, Sargassum can be removed in shallow waters using fishing nets that are towed by small boats or manually.

Lapointe stated that in the US, many people clean up with Barber beachrakes pulled by a tractor. The rakes won't work well if there is more than one foot of sargassum. Front-end loader dump trucks are useful, but can also be dangerous for beach health.

Dump trucks can be used to remove sargassum.

Lapointe stated that sea turtle nests are often found on beaches where they are being crushed by heavy equipment.

What happens to sargassum if it isn't removed?

Lapointe stated that if sargassum isn’t removed from beaches or used as fertilizer the arsenic in its flesh can leach into groundwater which could pose a danger to human health.

A high amount of rotting Sargassum can support the growth and development of fecal bacteria.

Lapointe stated that in 2018, a huge bloom ended up on South Florida's beaches, which coincided with the largest red tide that had ever been seen on that coast. Red tides are caused by toxin-producing algal blooms that grow out of control and discolor the coast. Red tide organisms can survive on sargassum, and they can be transported by it.

Red tides can cause harm to marine life. Sargassum buildup on beaches can also prevent sea turtle hatchlings from reaching the sea.

This will happen every year.

Lapointe stated that experts don't know if a sargassum flower of this size will occur every year.

He said, "It's difficult to project because it's not easy to know everything about the drivers (behind that)," "We know that it is variable from one year to the next and that the trajectory is generally going up. Based on the past experience, we believe that this could get worse over time. What will it look like in 10 years' time? It will be twice as big in 10 years.

He said that more funding is required to conduct the research necessary to answer these questions.