Ocean Acidifying Faster Than Any Time in 300 Million Years, Study Says

The world’s oceans may be acidifying faster today than during any period over the last 300 million years, a phenomenon that could have dire consequences for marine species and ecosystems, according to a new study. In a review of hundreds of paleoceanographic studies, a team of scientists found that a steep rise in atmospheric levels of carbon dioxide has driven down pH levels in oceans by 0.1 over the last century, to about 8.1, a rate 10 times faster than the closest historical comparison — a period of acidification 56 million years ago that triggered a massive ocean die-off. Oceans are vulnerable because they absorb excess CO2 from the atmosphere, turning the water more acidic, which can inhibit organisms, such as oysters and coral reefs, from forming shells. Barbel Honisch, a paleoceanographer at Columbia University’s Lamont-Doherty Earth Observatory and lead author of the study, published in Science, said “if industrial carbon emissions continue at the current pace, we may lose organisms we care about — coral reefs, oysters, salmon.”