Ocean chemistry changing at 'unprecedented rate'

Carbon dioxide emissions that contribute to global warming are also turning the oceans more acidic at the fastest pace in hundreds of thousands of years, the National Research Council reported Thursday. "The chemistry of the ocean is changing at an unprecedented rate and magnitude due to anthropogenic carbon dioxide emissions," the council said. "The rate of change exceeds any known to have occurred for at least the past hundreds of thousands of years." Ocean acidification eats away at coral reefs, interferes with some fish species' ability to find their homes and can hurt commercial shellfish like mussels and oysters and keep them from forming their protective shells. Corrosion happens when carbon dioxide is stored in the oceans and reacts with sea water to form carbonic acid. Unless carbon dioxide emissions are curbed, oceans will grow more acidic, the report said. Oceans absorb about one-third of all human-generated carbon dioxide emissions, including those from burning fossil fuels, cement production and deforestation, the report said. The increase in acidity is 0.1 points on the 14-point pH scale, which means this indicator has changed more since the start of the Industrial Revolution than at any time in the last 800,000 years, according to the report.