Last year鈥檚 5,500-mile-long swath of yellow-brown seaweed stretching over the Atlantic Ocean from West Africa to the Gulf of Mexico was called the Great Sargassum Belt. Perhaps what鈥檚 growing out there this year should be christened 鈥渃olossal.鈥�
Researchers at the University of South Florida鈥檚 satellite-based Sargassum Watch System said last year鈥檚 sargassum bloom was so big it posed challenges on a hemispheric scale for marine ecosystems and coastal towns in terms of tourism, fishing, and marine life.
The size of this upcoming summer鈥檚 fledgling bloom is already setting records.
鈥淪argassum abundance in the interior central Atlantic increased, but it increased so substantially that the abundance reached a new record from all previous December months,鈥� the USF sargassum experts published online. 鈥淭his indicates that 2024 will be another major Sargassum year.鈥�
The weight of last year's sargassum belt was estimated to be 13 million tons at its peak. Going into this month, researchers predicted its weight was already approaching 5 million tons, which is up from one million tons in November.
The USF College of Marine Science will receive about half of a $3.2-million grant from the NOAA Monitoring and Event Response for Harmful Algal Blooms program, which is a five-year collaboration that aims to better forecast sargassum blooms and to discover how to prevent them from plaguing coastal communities.
Parts of the Sunshine State鈥檚 coastline, particularly along the eastern shores of the Florida Keys, were among the beaches that had to contend with environmental, economic, and social challenges due to feet-deep accumulations of sargassum last year.
Galveston and South Padre Island along Texas鈥� Gulf Coast saw substantial amounts of Sargassum washing ashore, as did islands in the eastern Caribbean such as Barbados, Trinidad and Tobago, and St. Lucia faced severe impacts.
There was so much sargassum it also inundated West African coastal countries such as Ghana and Senegal.
Sargassum piling up feet-deep on many of the beaches, day after day, poses challenges for local authorities on how to clear the beach and minimize impacts on tourism and marine habitats.
As the seaweed decomposes it becomes unsightly, attracts insects, smells like rotten eggs as it emits hydrogen sulfide, and causes other environmental headaches such as smothering turtle nesting sites, increasing hatchling deaths, and causing fish kills.
The Optical Oceanography Laboratory at USF鈥檚 College of Marine Science tracks the seaweed from where it originates, which is a region of the tropical Atlantic known as the Sargasso Sea where the huge mats of yellow-brown algae swirl about on ocean currents. Toward the summer the mats drift throughout the Caribbean and Gulf of Mexico.
Floating in the ocean sargassum mats are standalone ecosystems important to many marine animals. It provides fish, shrimp, crabs, and turtles with food, shade, and protection from predators. On the beach, sargassum may serve as fertilizer for plants that grow on dunes and thus contribute to shoreline stability. The seaweed is also being studied as a possible source of pharmaceutical materials.
USF鈥檚 College of Marine Sciences will be working with Florida Atlantic University, the Caribbean Coastal Ocean Observing System, NOAA鈥檚 Atlantic Oceanographic and Meteorological Laboratory, and the U.S. Virgin Islands Department of Planning and Natural Resources on NOAA鈥檚 $3.2 million grant to improve satellite-based sargassum forecasting.
鈥淭he goal is to be able to put a single beach on alert when a sargassum inundation is imminent, instead of alerting the entire Caribbean,鈥� said Brian Barnes, a USF oceanographer. 鈥淭his increased level of resolution will give coastal resource managers more time to prepare for and ameliorate the effects of inundation events.鈥�
Environmental reporting for WGCU is funded in part by , a non-profit with a mission to accelerate change and global impact by supporting science-based climate solutions, enhancing education, and improving health.
Copyright 2024 WGCU. To see more, visit .
