Scientists warn of ‘regime shift’ as seaweed blooms expand worldwide

Study links rapid growth of ocean macroalgae to global heating and nutrient pollution

Scientists have warned of a potential regime shift" in the oceans, as the rapid growth of huge mats of seaweed appears to be driven by global heating and excessive enrichment of waters from farming runoff and other pollutants.

Over the past two decades, seaweed blooms have expanded by a staggering 13.4% a year in the tropical Atlantic and western Pacific, with the most dramatic increases occurring after 2008, according to researchers at the University of South Florida.