Seaweed Blooms Suggest The Ocean Is Geoengineering Itself - CleanTechnica

A 2026 study led by researchers at the University of South Florida used AI-driven analysis of 20 years of satellite data to reveal a significant global increase in floating macroalgae (seaweed) blooms, with rapid expansion starting around 2008–2010. This marks a notable shift from a previously macroalgae-poor ocean to one increasingly rich in floating seaweed, such as sargassum, which forms massive blooms like the Great Atlantic Sargassum Belt visible from space. While these blooms can support marine life offshore, their arrival on coastlines poses threats to ecosystems, tourism, and local economies. The study provides the first comprehensive global picture of floating algae, showing that macroalgae coverage increased by about 13.4% annually between 2003 and 2022, far outpacing the modest 1% annual rise in microalgae like phytoplankton. The researchers identified key tipping points in bloom growth around 2008–2012 and