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Concern Rising Over Massive Annual Seaweed Invasion in West Africa

FILE - Sargassum seaweed blankets Lumley beach, Freetown, Sierra Leone, Oct. 1, 2015. ( Vries/VOA).

FILE - Sargassum seaweed blankets Lumley beach, Freetown, Sierra Leone, Oct. 1, 2015. ( Vries/VOA).

Large amounts of seaweed have been washing up on the beaches of Sierra Leone and other countries in West Africa and the Caribbean. Scientists say climate change may be to blame. Local environmental protection authorities plan to bring it up at the U.N.’s climate change summit in Paris, which starts Monday.

As Sierra Leone is trying to bounce back from the worst Ebola outbreak in history, it now is turning attention back to other pressing issues, including excessive seaweed on its pristine beaches.

The problem has been apparent for the past several years during the country’s rainy season, which can last about six months.

The beaches become entirely blanketed with sargassum seaweed. It’s normal to have some of this seaweed, but not the amount that’s been showing up lately.

Climate change may be a factor.

Climate change impact

Edward Bendu, the acting chief environment officer for the Ministry of Lands and the Environment, hopes some solutions may come from the Paris summit.

“And so seaweed, having erupted, emerged massively, along the west coast of West Africa should be a topic that should be discussed in one of those sessions,” he said.

This phenomenon has also been happening in the Caribbean.

Raymond Johnson in Sierra Leone is one of the scientists who has been doing research on the seaweed invasion.

He says the algae relies on nutrients in the sea. When those elements are there in large quantities, the algae can then grow bigger and multiply.

Johnson adds that warmer ocean temperatures could be what is causing more seaweed to make its way to West Africa from the north Atlantic ocean where it grows.

Warmer oceans

He says when oceans are warmer, that can intensify wind patterns, which then affect the speed of ocean currents. This can all be linked to climate change, he says.

“If the ocean is warming, that increase heat of ocean water results in increased exchange with the atmosphere, so that increases heat flux, heat movement between the atmosphere and the ocean, that influences the dynamics of the ocean,” he said.

This massive amount of seaweed also has those in the tourism industry worried. Even though it washes up mainly in the rainy season and tourists do not come as much then, it still looks unappealing. And has a horrible smell, says Yassin Kargbo, general manager of the National Tourist Board.

“We realize it’s something that could cripple the entire tourism industry, especially the beach tourism industry, we see we need to work on it,” said Kargbo.

He adds ways of using the seaweed to the country’s advantage are currently being discussed. Including using it as bio fuel or turning it into fertilizer for the agricultural industry.