April 14, 2020 By Dan Nosowitz Atlas Obscura
Sargassum is the umbrella term for a group of marine algae species—within a larger group called seaweed—that’s fundamental to the health of an entire region of the Atlantic and the many species who either live there or pass through. Sometimes, though, it explodes in growth, creating a continent-sized bloom that thoroughly freaks out multiple countries. These blooms have long happened and are perfectly acceptable if they happen rarely. They have not been happening rarely.