Will regulators OK controversial effort to supercharge ocean’s ability to absorb carbon?

By Warren Cornwall, Science. 

Excerpt: Geoengineering study that would disperse alkaline chemicals off Cape Cod draws environmental opposition. Adam Subhas ...has spent much of his career as a chemical oceanographer at Woods Hole Oceanographic Institution (WHOI), quietly studying how seawater can naturally offset global warming by absorbing carbon dioxide (CO₂). Now, Subhas has been thrust into a heated public debate. Next month he and his colleagues want to dump tons of caustic chemicals off the coast of Massachusetts to see whether they can boost the ocean’s uptake of CO₂. They’re seeking what would be the first-ever regulatory approval for such a study from the U.S. Environmental Protection Agency (EPA). But some nearby residents and environmental groups, worried about safety, have pressed EPA to delay or halt the study. “It’s been a new journey to interact with reporters and the public and everyone at this level and at this intensity,” Subhas says. ...The natural alkalinity of the ocean already allows it to absorb 10 billion tons of CO₂ every year, equivalent to roughly one-quarter of society’s annual CO₂ emissions from burning fossil fuels. Alkaline molecules contained in rocks such as limestone erode into the ocean, where they react with dissolved CO₂ to form relatively inert chemicals such as bicarbonate, which can persist unchanged for millennia. Depleted of CO₂, the ocean can then absorb more out of the atmosphere. Adding more alkaline chemicals or rocks to the ocean would boost this process. But the approach has major unanswered questions, including whether tweaking ocean chemistry might affect ecosystems, how much CO₂ would really be captured, .... 

Full article at https://www.science.org/content/article/will-regulators-ok-controversial-effort-supercharge-ocean-s-ability-absorb-carbon. For GSS Climate Change chapter 10.