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Pacific Ocean Increases Acidity by 6 percent (a lot) in 20 Years

By January 25, 2010February 24th, 2013Oceans

From the Seattle Times, Jan 20, 2010:

"If you see these changes across an entire ocean basin, you can be assured it’s happening on a global scale in other ocean basins around the world," said Robert Byrne, a marine chemist at the University of South Florida and lead author of an upcoming paper in Geophysical Research Letters.

Ocean acidification is a threat to shelled creatures and other marine life, and is a leading suspect in the ongoing crash of Pacific oyster populations in Washington.

Byrne collaborated with Seattle scientists on the survey, which was 15 years in the making. The team first measured acidity along the 2,800-mile sweep of ocean between Oahu and Kodiak in 1991. They returned in 2006 aboard the University of Washington research vessel Thomas G. Thompson, working around the clock in shifts to collect and analyze nearly 1,500 water samples over two months.

Byrne said: “Over the past 15 years, average pH levels in the top 300 feet of the ocean dropped 0.026 pH units. That sounds tiny, but is equivalent to a 6 percent jump in acidity … Analysis of air bubbles trapped in Antarctic ice cores show that atmospheric carbon dioxide already is higher than anytime in the last 800,000 years, and the same is almost certainly true of ocean acidity, Byrne pointed out. Since the start of the Industrial Age, the scientists calculate that the acidity of the world’s oceans has increased by 25 to 30 percent.”