Ocean's Keystone Species Threatened by Climate Change

New research reveals that Prochlorococcus, the smallest and most abundant phytoplankton on Earth, is significantly threatened by climate change. As ocean temperatures rise, this microscopic bacterium—crucial to the marine food web and climate regulation—could decline by as much as half in tropical oceans within the next 75 years. The study, based on a decade of data collected across extensive ocean voyages, highlights the worrying trend. The reduction in Prochlorococcus will have profound impacts on marine ecosystems, biodiversity, and even human food supplies. Researchers urge a reduction in greenhouse gas emissions to mitigate this threat.