Because of natural tide and wave patterns, the Pacific Northwest Coast has been hit hardest, with corrosive water being brought up from the deep ocean to the surface, where shellfish live. HARI SREENIVASAN: All that CO 2 changes the chemistry of the water by making it more acidic, 30 percent more since the start of the Industrial Revolution. And about a quarter of that, or 550 billion tons of carbon dioxide, have been absorbed by the oceans. RICHARD FEELY: Over the last 200 years or so, we have released about two trillion tons of carbon dioxide into the atmosphere. HARI SREENIVASAN: That switch is happening around the world as oceans take in large amounts of carbon dioxide, or CO 2, says Dick Feely, a senior scientist at the National Oceanographic and Atmospheric Administration.
When the water was high pH, they did just fine. When the waters were highly corrosive, the organisms died within two days. RICHARD FEELY, National Oceanic and Atmospheric Administration Pacific Marine Environmental Laboratory: And what we found was just very dramatic. HARI SREENIVASAN: Seed production in the Northwest plummeted by as much as 80 percent between 20. And it's most of which, I understand a tiny fraction of, but what I do understand is when the nursery calls on the phone and says there's no oyster seed to ship, we don't have any. It's the currents, it's the carbon dioxide, it's the aragonite.
SHINA WYSOCKI: Ocean acidification is a huge problem. The culprit? The seawater pumped into the hatcheries is so corrosive that it eats away the young oyster shells before they can form.
But a few years ago, the larvae suddenly began dying by the billions. Most growers like the Wysockis can only farm oysters if they can buy oyster larvae, also called oyster seed, from hatcheries. The ocean's pH, which measures the level of acidity of a liquid, shows the water is becoming acidified. HARI SREENIVASAN: But there's trouble in the water. SHINA WYSOCKI, Chelsea Farms: We think our water tastes great here, and that makes our oysters taste great. HARI SREENIVASAN: Pacific oysters like the ones grown on Shina Wysocki's family farm near Olympia, Wash., are served in restaurants around the country.
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