Ocean acidity may increase by 170% by end of century

Global ocean acidity may increase by 170 percent by the end of the century, bringing significant economic losses, experts conclude in an international report. The group of experts has agreed on "levels of confidence" in relation to ocean acidification statements from the world's largest gathering of experts on ocean acidification ever convened, the International Council for Science reported from its Paris headquarters Thursday. "What we can now say with high levels of confidence about ocean acidification sends a clear message," Ulf Riebesell of the GEOMAR Helmholtz Center for Ocean Research in Kiel, Germany, said. "Globally we have to be prepared for significant economic and ecosystem service losses." Marine ecosystems and biodiversity are likely to change as a result of ocean acidification, with far-reaching consequences for society, the experts agreed. If society's high emissions are not curbed, cold-water coral reefs located in the deep sea may be unsustainable and tropical coral reef erosion is likely to outpace reef building this century, the experts said. However, they said, significant emissions reductions could ensure that half of surface waters presently occupied by tropical coral reefs remain favorable for their growth. Threats to ocean health would still remain, said report author Wendy Broadgate, Deputy Director at the International Geosphere-Biosphere Program. "Emissions reductions may protect some reefs and marine organisms but we know that the ocean is subject to many other stresses such as warming, deoxygenation, pollution and overfishing," she said. "Reducing other stressors such as pollution and overfishing, and the introduction of large scale marine protected areas, may help build some resilience to ocean acidification."