Dear Editor,
On the beaches of St. Martin, a new environmental challenge has emerged – one not shaped by storms or erosion, but by an overabundance of Sargassum seaweed. Once a natural and largely unnoticed component of the marine ecosystem, Sargassum has surged in both volume and visibility, blanketing the island’s iconic beaches and unsettling the twin pillars of its economy: tourism and environmental health.
The arrival of Sargassum in such overwhelming quantities has become a defining issue for the Caribbean region. On popular coastlines like Orient Beach, thick mats of seaweed wash ashore with the tides, pile up in decaying mounds, and release a pungent odor as they rot – emitting hydrogen sulfide, a gas that poses health risks to residents and visitors alike. The sheer volume has left hoteliers and local governments scrambling for solutions.
Crews begin work as early as 5 a.m., according to local contractors, using bulldozers, pickup trucks and manual labor to clear the beaches. Despite these efforts, new deposits arrive almost daily, brought in by shifting currents and overnight tides. One contractor candidly described the challenge as “a long-term problem without a quick solution.”
But what’s driving this phenomenon? According to scientists, changes in ocean temperature, wind patterns, and currents – largely attributed to climate change – are fueling unprecedented Sargassum growth. As surface waters warm, they create conditions ideal for Sargassum blooms, in much the same way that warm waters fuel hurricanes. Warmer temperatures accelerate growth, while shifts in currents carry vast rafts of seaweed from the Sargasso Sea into the tropical Atlantic and, ultimately, onto Caribbean shores.
Dr. Ajit Subramaniam, a biological oceanographer at Columbia University’s Lamont-Doherty Earth Observatory, explains that this transformation in ocean dynamics has created “massive rafts of seaweed affecting the beaches off the Caribbean.” Once confined to the open ocean, Sargassum now inundates coastlines from Mexico to Martinique and St Martin.
To understand and address the issue, Dr. Subramaniam is leading research into the feasibility of deep-sea sequestration. The idea involves trapping the Sargassum offshore and sinking it to depths of at least 2,000 meters, where it could potentially store carbon and reduce surface bloom impacts. This approach would not be a permanent solution, but it could offer critical breathing room while more comprehensive strategies are developed.
Meanwhile, St. Martin is not standing still.
Sebastian Price and Deirdre Frost
