The three maps show model data of how the availability of calcium carbonate (which depends on ocean water pH) is predicted to decrease over the next century at a depth of 10 meters in the ocean—where most coral live. Blue indicates waters that have enough calcium carbonate for shell-building creatures such as coral. Areas colored deep red are expected to be sufficiently acidic by 2100 that they would dissolve shell-building organisms. Based on model data from Orr, J.C. et al. (2005), Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms, Nature, 437, 681-686.

Image Credit: 
NOAA Environmental Visualization Lab