Great Barrier Reef
Not all the carbon dioxide we emit contributes to atmospheric warming. More than a third of what we have produced since the industrial revolution has been absorbed by the oceans, where it reacts with seawater to form carbonic acid. So far, weve added enough carbon to shift the pH of the worlds waters from 8.2 to 8.1.
The first to feel the impact are the creatures of the sea that use calcium carbonate to form their shells and exoskeletons. The acidic or actually less alkaline water wears away at crabs, mollusks and sea snails. Coral reefs face a double whammy as the changing ocean chemistry adds to the stress of unusually warm water. Australias Great Barrier Reef lost an estimated 10 percent of its coral to mass bleaching in 1998 and 2002. Overstressed colonies expelled the symbiotic algae that give them their color, leaving them bone white and weakened. The U.N. Intergovernmental Panel on Climate Change IPCC estimates that by 2050, 97 percent of the Great Barrier Reef will be bleaching yearly. Whereas the coral sometimes recovers, reabsorbing the algae, more often bleaching is the first step toward death.
The oceanic kaleidoscope may be among the first victims of the changing waters, but the devastation can be expected to work its way up the food chain. In Australia the seabird population has begun to drop steeply. The seafood industry could be next. As the reefs vanish, the fish will surely follow.
Top 10 Places Already Affected by Climate Change: Scientific American Slideshow
