A 20-year study of the Pacific Ocean waters northwest of Hawaii has documented a sustained rise in the water’s acidity caused by air pollution, a change that could lead to a cascading effect on ocean life if not checked.
“Only by doing it in this long-term fashion can we say confidently that the ocean is getting more acidic,” said John Dore, lead author of the study recently published in the Proceedings of the National Academy of Sciences. Dore is a professor in the Department of Land Resources and Environmental Sciences at Montana State University who has been working on the Hawaii Ocean Time-series project for 18 years.
He said fluctuations in ocean acidity occur naturally, making it difficult for researchers to separate out the increase from the “background noise.” But with 20 years of data, the rise was easier to document.
“It’s surprising how difficult it is in practice to refute this or confirm it,” Dore said. “There’s a lot of debate about if it’s going on and the effects.”