Pteropods are sometimes called sea butterflies, and salmon, whales and other marine life eat these little snails. And scientists have found that their shells, which contain calcium carbonate, are
sensitive to changes in the ocean’s pH levels.
That’s where climate change comes in. Carbon dioxide from human activities ends up in the ocean, increasing the acidity of seawater. As the pH level falls and water becomes more corrosive, calcium carbonate in pteropod shells dissolves.
While the potential for this problem had been demonstrated in labs, last year National Oceanic and Atmospheric Administration scientists
were surprised to discover that damage to pteropod shells in the Pacific Ocean had already started. The ocean acidification that damages pteropods could have manifestations in
other marine species, too, creating distress on the ocean’s food web.
http://www.nytimes.com/interactive/...-change-looks-like-dissolving-pteropod-shells
Most of the earth's oxygen comes from the ocean. If it's ecosystem collapses this producer of oxygen could become a huge dead zone that absorbs oxygen as the plankton die.
