About a third of the CO2 we send up into the air goes into our seas. There it forms carbonic acid which reduces the pH – or raises the ‘acidity’ - of our oceans. The phenomenon is referred to as ‘ocean acidification’. This increased acid naturally combines with calcium-carbonate in the water, making it less available to those creatures that rely on it—such as mollusks, sea stars, crabs, and myriad microscopic organisms. The ocean’s chemistry is thought to be changing 10 times faster than it did during the last major acidification, 55 million years ago, and through food-web effects, is expected to impact more than just “calcifiers.” We’re only just beginning to learn the extent of its impacts.
The recent National Geographic, has an excellent article on this topic by science writer Elizabeth Kolbert. It’s a must read.
Kolbert takes us first to an island in the Tyrrhenian Sea, where volcanic vents bubble CO2 into the water, providing a natural laboratory and potential window to our future oceans; then she travels to another island in Australia, where coral reefs are under duress, because they, too, need calcium for their hard, slow-growing skeletons. Additionally, photographer David Liittschwager provides beautiful photos that chillingly illustrate the potential devastation acidification may have on our sea creatures.
For more information on acidification, watch NRDC’s short video, Acid Test, which further explains the peril.