Some Corals More Resilient To Increased Acidification, Study Shows

Some coral species may be better able to cope with the increasingly acidic condition of the world’s oceans than previously believed, a new study says. Writing in the journal Nature Climate Change, an international team of scientists describes an internal mechanism by which many coral species are able to buffer against the rising pH levels and still form healthy skeletons. According to the scientists, coral species with skeletons made of aragonite — including the well-known Porites and Acropora corals — contain molecular “pumps” that enable them to regulate internal acid balance. Corals that form calcite skeletons, however, do not have this mechanism. Also, the researchers found that coralline algae — which they describe as the “glue” that holds coral reefs together — remain vulnerable to ocean acidification. In another study, scientists at the Scripps Institution of Oceanography have documented how temperatures in the upper regions of the world’s oceans have increased by an average of .59 degrees F (.33 degrees C) over the last 140 years, with the greatest temperature increases occurring at surface levels, where temperatures rose by an average of 1.1 degrees F.