http://www.slate.com/articles/health_and_science/science/2015/11/ocean_acidification_and_climate_change_at_the_paris_talks.html
"there’s increasing evidence that the world’s oceans are nearing the point of no return. They’re getting hit with a double whammy—rising temperatures and acidification—that together are forcing fundamental changes to the basis of the planet’s food chain. So far, the oceans have absorbed about 93 percent of all the additional heat energy trapped by rising greenhouse gas concentrations. That’s already prompted the loss of about 40 percent of the world’s coral reefs, accelerated by a series of worldwide bleaching events in which exceptionally warm water temperatures prompt normally symbiotic algae to become toxic—the most recent of which was just this year. Since coral reefs—the “rainforests of the sea”—support a quarter of all marine life on just 0.1 percent of the ocean area, a mass extinction may already be underway. If we lose the oceans, we lose everything."