Scientists have long been concerned that decreasing ocean pH (increasing acidity) caused by increasing carbon dioxide emissions in the atmosphere could negatively impact coral reefs. Many laboratory experiments have demonstrated that increased ocean acidity slows down coral calcification, the process by which corals grow and build their hard structure. But far fewer studies have tested how increasing ocean acidity affects coral growth in the natural environment, where a multitude of additional factors such as light, temperature, and nutrients are also important.

A new paper based on research led by scientists at Scripps Institution of Oceanography at the University of California San Diego that was published this week in Science Advances found a surprising answer to this question. Scripps chemical oceanographer Andreas Andersson, his graduate student Travis Courtney, and an international team of collaborators from the Bermuda Institute for Ocean Sciences and Christian-Albrecht University in Germany, among others, were involved in the study funded by the National Science Foundation.