No More Speculation: Scientists Prove Ocean Acidification is Already Underway | 80beats | Discover Magazine No More Speculation: Scientists Prove Ocean Acidification is Already Underway While concerns over ocean acidification are not new, a recent study provides more concrete evidence than ever before that the process has already begun. Australian scientists found that shells of the microscopic, amoeba-like organisms called foraminifera, which exist by the billions in oceans around the world, have become significantly thinner since the Industrial Revolution. The study, published in Nature Geoscience, is the first to look specifically at acidification and pin it to greenhouse-gas pollution, which is driven especially by the invisible product of burning oil, gas and coal. It is the invasion of anthropogenic (man-made) CO2 that is causing this particular source of acidification, said co-author William Howard [AFP]. The research team compared newer shells of Globigerina bulloides, a species of foraminifera, with shells of the same species that had sunk hundreds of years earlier; the modern shells were found to be 30 to 35 percent lighter than older specimens of about the same size. The older shells predate the industrial age, when CO2 levels started rising and the acidity of the ocean, caused by the absorption of the gas, began to increase . As ocean acidity increases, the saturation levels of carbonate minerals in the water decreases, making it more difficult for organisms to precipitate out the carbonate for their shells [The New York Times].