Ocean temperature is now the primary climate-induced threat to North Atlantic calcifying plankton, reports work published online in Nature Climate Change. This study suggests that although ocean acidification may become a serious threat in the future, from 1960-2009 the primary driver of change was ocean temperature.

Gregory Beaugrand and co-workers investigated the effects of ocean acidification and temperature change on marine-calcifier diversity in the North Atlantic Ocean. By analysing biological data and physical parameters, they show an abrupt shift in plankton communities around 1996, corresponding to a substantial temperature increase. They also note that some species showed poleward movement, in agreement with expected biogeographical changes under ocean warming.