Wednesday, December 08, 2021

Should We Electrocute The Oceans To Curb Climate Change? That’s One Idea.

Chris D'Angelo
Wed, December 8, 2021

Some of the nation’s leading ocean and climate scientists are calling on the U.S. government to invest up to $1.3 billion in research on human interventions that could boost the oceans’ ability to suck up planet-warming carbon dioxide in the coming decades.

The recommendation is part of a new, 300-page National Academy of Sciences report released Wednesday that explores six techniques for accelerating ocean CO2 removal and storage, some more radical than others. Potential areas of study include restoring degraded ecosystems, large-scale seaweed farming, dumping nutrients like iron and phosphorus in the water to promote plankton growth, and even jolting seawater with electricity to make it less acidic.

The report outlines known risks and benefits, as well as costs and scalability, in order to provide policymakers with a framework for deciding next steps. It does not advocate for any individual tool or technology.

“All of these approaches have some combination of tradeoffs and there are substantial knowledge gaps,” Scott Doney, an oceanographer at the University of Virginia and chair of the NAS committee that authored the report, told HuffPost. “It’s really trying to find investments on the research side that could fill those gaps in a way that would better prepare us to make those decisions.”

An oil platform is pictured in the Persian Gulf. (Photo: Dario Argenti via Getty Images)

Burning of fossil fuels and other human activities have driven atmospheric carbon dioxide levels to their highest point in 800,000 years, and there is a growing consensus among the world’s leading scientists that staving off potentially catastrophic climate change will require more than simply cutting greenhouse gas emissions going forward. A 2019 NAS report, for example, found that the world will have to find ways to remove approximately 10 gigatons of CO2 from the atmosphere each year by mid-century to limit global warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit), the goal of the landmark Paris climate agreement.

If it weren’t for the oceans, Earth’s largest carbon sink, the planet would already be significantly warmer. Oceans have absorbed an estimated 93% of the excess heat from human-caused climate change, and climate scientists and advocates have increasingly pushed for countries to use them as a key tool to meet climate goals and achieve the 1.5 degree target.

“The ocean holds great potential for uptake and longer-term sequestration of human-produced CO2,” the NAS report states.

In this photograph taken on Sept. 24, 2021, women work to cultivate fronds of seaweed on bamboo rafts in the waters off the coast of Rameswaram in India's Tamil Nadu state. (Photo: ARUN SANKAR via Getty Images)

Of the six possible techniques, NAS’s initial assessment concluded that nutrient fertilization and introducing electrical currents were among the most likely to prove effective at enhancing CO2 storage. But both come with significant environmental risk.

“We want to do it in a thoughtful way that avoids environmental damages, that avoids negative social or ecological impacts,” Doney said. “But there’s an urgency to start reducing emissions relatively soon.”

“I don’t want to be 5 or 10 years from now and not have done some of this foundational research that we’ve recommended on the social dimensions, governance and carbon accounting,” he added.

The NAS panel recommended an initial $125 million to fund a U.S. program to study the challenges and potential impacts of ocean carbon removal, with additional funding up to $1.2 billion over the next 10 years to conduct in-depth research into each of the six techniques.

Jan Mazurek, senior director of ClimateWorks Foundation, which sponsored the study, called it a “scientific road map for how healthy oceans can cool the climate.”

“The ocean is the heart of our planet, but the world’s fossil fuel addiction has pumped it full of CO2 and turned it more acidic, giving sea life the equivalent of heartburn disease,” she said in a statement. “We cannot live healthily if our oceans are sick.”

Panel: Consider tinkering with oceans to suck up more carbon

By SETH BORENSTEIN

 A man wades into the ocean at sunset, Tuesday, June 22, 2021, in Newport Beach, Calif. In a report released Wednesday, Dec. 8, 2021, the National Academy of Sciences says to fight climate change the world needs to look into the idea of making the oceans suck up more carbon dioxide. (AP Photo/Jae C. Hong, File)

The United States should research how to tinker with the oceans — even zapping them with electricity — to get them to suck more carbon dioxide out of the air to fight climate change, the National Academy of Sciences recommends.

The panel outlines six ways that could help oceans remove more heat-trapping carbon dioxide from the atmosphere. The scientists said the most promising possibilities include making the seas less acidic with minerals or jolts of electricity, adding phosphorous or nitrogen to spur plankton growth and creating massive seaweed farms.

But it’s unknown if they would work, would cost too much or cause more harm than good. So the panel of science advisers to the federal government Wednesday proposed spending more than $1 billion over the next decade to figure out the potential pitfalls and most effective methods of getting the world’s oceans to suck up more carbon.

The issue needs to be examined, the academy said, because something more than reducing carbon emissions likely needs to be done to take heat-trapping gases out of the air if the world is to meet the 2015 Paris climate goals of limiting future warming to a few more tenths of a degree from now.

By mid-century, the world will probably need to take about 10 billion metric tons of carbon dioxide out of the air annually, the report said.

Previous academy reports looked at geoengineering as well as efforts to take in carbon, including planting more trees. This new report, funded by the non-profit ClimateWorks, examines what’s now absorbing most of excess carbon dioxide: the seas.

The report doesn’t advocate geoengineering the oceans, just exploring how it could be done.

“We don’t answer the question, ’Should we’?” said panel chairman Scott Doney, a biogeochemist at the University of Virginia. “The question is, ‘Can we?’ And if we do, what would be the impacts, and one of the things we try to highlight is that all of these approaches will have impacts.”

“What are the consequences to the environment?” Doney said.

The report looked at the following ways for oceans to take more carbon dioxide from the air:

— Electrical jolting the oceans to make them less acidic. Water that’s more alkaline can suck up more carbon. It also helps fight one of climate change’s harms — acidic ocean waters that damage shellfish and reefs. Scientists are confident the approach would work because it is basic chemistry, Doney said. But it bears the highest cost and medium to high risks. The report recommends $350 million in research.

— Using minerals to make the ocean to make it less acidic. This would be somewhat expensive and risky, and the report recommends $125 million to $200 million for research.

— Adding nutrients such as phosphorus or nitrogen to the ocean surface. This would spur photosynthesis by plankton, which would breathe in the carbon dioxide then sink. The panel had medium to high confidence that it would work, with medium environmental risks, and recommended $290 million in research and field experiments.

— Seaweed farming with the plants taking up carbon then sinking into the deep ocean or getting pumped there. There’s medium confidence this would work with medium to high environmental risks. The panel suggests $130 million in research.

— Ecosystem recovery would help marine animals, plants and the coastal environment become healthier and absorb more carbon. It has low environmental risk but also low to medium chances of working. The report estimates $220 million in research.

— Artificial waves creating upwelling and downwelling to stimulate plankton growth. The confidence in this working is low, the risks high, and the report recommends $25 million in research.

Breakthrough Institute climate scientist Zeke Hausfather, who wasn’t part of the study, said the electricity and chemical approaches to change ocean acidity “have the highest potential for long-term carbon removal at a scale large enough to make a meaningful impact.” But he said he’s more skeptical of ocean fertilization to stimulate plankton.

Cornell University climate scientist Natalie Mahowald, who also wasn’t part of the study, said, “Carbon removal and sequestration is required to reach low climate targets. ... The ocean represents huge un-understood and untapped potential.”

But Pennsylvania State University climate scientist Michael Mann said merely by exploring the idea of tinkering with the ocean is harmful because polluters and government officials can use it as an excuse “to delay and downplay the only safe climate solution — dramatically curtailing our burning of fossil fuels.”

It makes sense to just be prepared, said panel chairman Doney. “If we don’t start down this road now of the research, we might have to make decisions with insufficient information.”

It’s up to the president and Congress to fund the research. Earlier this week the Department of Energy asked companies and organizations to demonstrate technologies that could remove carbon dioxide from the air or cut emissions, saying there’s funding for such work in the infrastructure law that passed last month.

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Read more of AP’s climate coverage at http://www.apnews.com/Climate

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Follow Seth Borenstein on Twitter at @borenbears

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.


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