Oceans Of Listerine

Well here’s another reason global warming sucks: The increase in carbon dioxide levels is rapidly making the world’s oceans more acidic and could lead to a massive extinction of marine invertebrates similar to the K-T event 65 million years ago.

When CO2 dissolves in the ocean, some of it becomes carbonic acid. The current rate of input is 50 times greater than the ocean’s sediments can absorb though. This will lead to a change in worldwide pH levels from 8.2 to 7.7 in under 100 years. Carbonic acid dissolves calcium carbonate, the basic building material of corals, plankton and mollusc shells. This could make it difficult for these animals to build shells and survive in the acidic waters.

The last time the oceans endured such a drastic change in chemistry was 65 million years ago, at about the same time the dinosaurs went extinct. Though researchers do not yet know exactly what caused this ancient acidification, it was directly related to the cataclysm that wiped out the giant beasts. The pattern of extinction in the ocean is consistent with ocean acidification–the fossil record reveals a precipitous drop in the number of species with calcium carbonate shells that live in the upper ocean–especially corals and plankton. During the same period, species with shells made from resistant silicate minerals were more likely to survive.