Brazil

Brazil, the largest country on the South American continent, has 60% of its total surface covered by the Amazonian rainforest. Its entire coastline, i.e. 8,500 kilometers, is on the Atlantic Ocean. The North of the Brazilian territory is crossed by the longest river in the world: the Amazon, which flows into the Atlantic Ocean.

There’s no official policy regarding Sargassum. The Brazilian coasts are not prone to massive events as other Caribbean territories. However, scientists, residents and professionals on the coasts of the North of the country in the Amazon estuary in the state of Pará, have observed an increase in the quantity of Sargassum since 2019. For example some fishermen mention a brown algae clinging to their nets and causing itching.

Since 2011, but even more so since 2018 when the phenomenon exploded, scientists around the world have been looking into the question of the proliferation of Sargassum and its movements in the Atlantic Ocean. The most popular theory in the scientific community regards the Congo river (one of the largest on the African continent which also flows into the Atlantic) and the Amazon river.

Both of these rivers carry an immense quantity of nutrients (mainly nitrates and phosphates), due to the mining activity, intensive cultivation and deforestation. These nutrients could be an important factor in the proliferation of Sargassum.

Observations show that the evolution of Sargassum in the Atlantic Ocean follows marine currents and nutrients carried by the two aforementioned rivers. The currents flow from the African Western coasts to the Caribbean coasts and to the Gulf of Mexico.