Projecting Coral Reef Futures Under Global Warming and Ocean Acidification

Many physiological responses in present-day coral reefs to climate change are interpreted as consistent with the imminent disappearance of modern reefs globally because of annual mass bleaching events, carbonate dissolution, and insufficient time for substantial evolutionary responses. Emerging evidence for variability in the coral calcification response to acidification, geographical variation in bleaching susceptibility and recovery, responses to past climate change, and potential rates of adaptation to rapid warming supports an alternative scenario in which reef degradation occurs with greater temporal and spatial heterogeneity than current projections suggest. Reducing uncertainty in projecting coral reef futures requires improved understanding of past responses to rapid climate change; physiological responses to interacting factors, such as temperature, acidification, and nutrients; and the costs and constraints imposed by acclimation and adaptation. Coral reefs occupy a small part of theworld’s oceans yet harbor a hugely dis-proportionate amount of its biodiver-sity. More than 450 million people from 109 countries live close to coral reefs, which provide important sources of ecosystem goods and services for these communities. But reefs have suffere