Washed up: Sargassum blankets beaches
30 July 2019
Over the last month, massive quantities of the Sargassum seaweed have been washing up on the shores of Mexico, Florida in the US and some Caribbean islands, creating a serious environmental problem and causing havoc for the tourist industry. ESA has been tracking this slimy infestation.
Sargassum is a large brown algae, first spotted by Columbus during his voyage to the Americas. Out at sea, Sargassum is an important habitat for marine species providing food, refuge and breeding grounds. However, when it collects along coastlines, it rots, producing a pungent smell and attracting flies. This can mean a real problem for tourism in coastal communities.
Sargassum, like other floating marine vegetation, absorbs atmospheric carbon dioxide – an important greenhouse gas that contributes to global warming – through photosynthesis and converts it into organic carbon.
A paper published recently in Science, The great Atlantic Sargassum belt, details how scientists have tracked this brown macroalgae using 19 years' of satellite data. Last year, for example, the brown belt hit a high, stretching 8,850 km from west Africa to the Gulf of Mexico – which is around the same length as the Great Wall of China.