About twelve years ago, operators of oyster hatcheries along the Oregon coast noticed something strange. Oyster larvae were dying. By the billions.

In short order, climate-change alarmists posited a cause: “ocean acidification” driven by manmade carbon dioxide (CO₂) emissions from burning fossil fuels.

Suddenly it wasn’t only warming of the atmosphere that struck fear into people’s hearts. Now it was a vision of “acidic” oceans playing havoc with all sorts of marine life. Shellfish couldn’t make shells successfully. Corals were dying. The lowest levels of the ocean food chain were threatened—and with them, billions of people who depend heavily on fish and other seafood for their nutrition.

YaleEnvironment360, published by the Yale School of the Environment, proclaimed in November 2011:

Northwest Oyster Die-offs Show Ocean Acidification Has Arrived. The acidification of the world’s oceans from an excess of CO2 has already begun, as evidenced recently by the widespread mortality of oyster larvae in the Pacific Northwest. Scientists say this is just a harbinger of things to come if greenhouse gas emissions continue to soar.

The idea remains common. Late last year, Portland, OR, television station KGW8 reported, “Changes to the ocean almost wiped out Oregon’s oyster industry.”

What changes were those? The presence of “high levels of carbon dioxide.” As a result, the oyster larvae couldn’t form shells, so they died, by the billions.

And some scientists quickly decided that fossil fuel burning caused the heightened levels of CO₂ in the water.

Environmentalists concerned about what they considered dangerous to catastrophic global warming driven by fossil fuel burning quickly seized on the news. Here was yet another reason why humanity must wean itself off of coal, oil, and natural gas and embrace “clean,” “renewable” wind, solar, and other non-carbon-based energy sources.

The claim remains widespread.

Meanwhile, however, evidence mounts that blaming the high CO₂ content of the ocean water of those hatcheries on rising atmospheric CO₂ driven by fossil fuel use was a mistake,

Ecological biologist Jim Steele explains the problem in Ocean Health—Is there an “Acidification” problem? It’s not that higher CO₂ concentration in the ocean water didn’t cause the problem. It’s that emissions from fossil fuel burning didn’t cause the higher CO₂ concentration in the ocean water.

The real source of the added CO₂ was increased upwelling of ocean water made rich in CO₂ thousands of years ago—upwelling that “has greatly increased since the Little Ice Age ended in the 1800s.”

“The failure to understand upwelling was costly to Oregon’s oyster hatcheries,” Steele writes.

Over-exploitation of North America’s native west coast oysters almost eliminated them. In response, oyster fisheries imported the Japanese oyster. However, that species was not well adapted to the more extreme upwelling along the Oregon and Washington coasts. Larval oysters often died when exposed to cooler upwelled waters. Furthermore, the more extreme tidal exchanges between the ocean and the estuaries caused free-swimming oyster larvae to be carried out to sea. Oystermen responded by developing hatcheries where larvae could safely develop, and then be released into the estuaries, where they settle and attach to surfaces.

But there was a problem:

… the non-native Japanese oyster larvae were not only sensitive to cooler upwelled waters. They were also sensitive to the lower pH of those upwelled waters. Unknowingly, hatchery operators filled their “nursery” tanks with water darwn from the estuary at the wrong time. Water was usually drawn in the early morning, after nighttime respiration had already lowered the water’s pH.

And it so happened that

… the operators piped in the estuary water right after an upwelling event. Tidal flushing had brought carbon-rich, low pH waters into the estuary. The use of this unusually low-pH water meant that many hatchery larvae did not survive. … the hatchery failure was deemed a crisis caused by global warming and ocean acidification. But by simply monitoring upwelling events, hatcheries can avoid making the same mistake.

To get the full picture of why “ocean acidification” didn’t harm Oregon’s oysters, why burning fossil fuels for energy isn’t causing “ocean acidification,” and indeed why “acidification” is a deceptive term for what’s really happening, read Ocean Health for yourself. You can get a copy FREE as our thanks for a donation of any size from now to the end of July 2020. Just go to our secure online giving page, or mail your check to Cornwall Alliance, 3712 Ringgold Rd. #355, Chattanooga, TN, or call us at 423-500-3009, make your donation, and ask for Ocean Health and mention Promo Code 20-07. Your gift will be 100% tax deductible.\

Featured image photo of oyster bed in the Pacific Northwest by Toan Chu on Unsplash.