Carpets of sargassum seaweed are covering South Florida beaches, creating a strong rotten-egg odor for visitors attending the 2026 FIFA World Cup [1, 2].
The timing of the bloom complicates the experience for thousands of international tourists who chose Miami as a destination for the tournament. The presence of the algae makes swimming and sunbathing difficult on the coastline [1].
Sargassum is a type of brown algae that blooms seasonally. These masses drift northward from the Caribbean and the Atlantic before washing ashore in South Florida [2]. The environmental impact is most evident in the scent produced as the organic material breaks down on the sand.
Environmental researchers said, "Sargassum smells like rotten eggs because it emits hydrogen sulfide as it rots" [2].
Local authorities in Miami have seen the algae blanket large stretches of the coast during this June window [1]. While the seaweed is a natural occurrence, the scale of the current bloom has significantly altered the aesthetic and olfactory environment of the city's primary tourist attractions.
Visitors have reported that the thick layers of brown algae obstruct access to the water. The decomposition process continues to release hydrogen sulfide gas, which lingers in the air along the shoreline [2].
“Sargassum smells like rotten eggs because it emits hydrogen sulfide as it rots.”
The intersection of a major global sporting event and a seasonal ecological phenomenon highlights the vulnerability of tourism-dependent cities to environmental shifts. As sargassum blooms become more frequent or intense due to Atlantic currents and nutrient levels, coastal cities must develop better mitigation strategies to maintain public health and tourism appeal.
