Geophys. Res. Lett. doi:10.1029/2008GL036282 (2009)

Say sayonara to coral reefs if carbon dioxide levels in the atmosphere reach 560 parts per million, roughly double their preindustrial level. Jacob Silverman of the Carnegie Institution in Stanford, California, and his colleagues reached this conclusion on the basis of field studies that measured coral growth as a function of factors such as ocean acidity and water temperature.

Those relationships suggest that at 560 parts per million of carbon dioxide the world's coral reefs cease to grow and start to dissolve. Unlike past studies, this one relied on measurements from actual coral reefs, rather than rates derived from studies in the lab or in large aquaria.