Geoengineering — the concept that says, “Don’t worry about more carbon dioxide and methane emissions. We will imitate the cooling effects of a massive volcanic eruption by pumping millions of tons of sulfur dioxide (the same gas belched out by volcanoes) into the atmosphere to cool things down.”
After Krakatoa erupted in August of 1883, average global temperatures fell by 1.2º C for the next five years. Since global temperatures today are about 1.2º C higher than they were 150 years ago, all we have to do is imitate what Krakatoa did and everything will be fine. We can go right on extracting and burning fossil fuels forever as long as we keep pumping sodium dioxide into the stratosphere. Ignore that unearthly red glow in the sky, folks. Nothing to see here. Move along.
Or we could deploy enormous mylar blankets high above the ionosphere to reflect sunlight back into deep space, paint all our buildings and roads white, or suck carbon dioxide out of the atmosphere and cram it down abandoned oil wells. If you are beginning to think geoengineering is pretty outlandish stuff, you’re not wrong. And yet some serious scientists think we should investigate the possibilities just because the world may arrive at a “We are so screwed!” moment and have to pull a rabbit out of the hat to save humanity from extinction.
Hacking The Ocean
A new 300-page report by the National Academies of Sciences, Engineering, and Medicine calls for scientific investigation into a number of ways of geoengineering the ocean so it can sequester more carbon dioxide. The report is entitled A Research Strategy for Ocean Carbon Dioxide Removal and Sequestration. Here’s the description of its objectives:
With the goal of reducing atmospheric carbon dioxide, an ad hoc committee will conduct a study exclusively focused on carbon dioxide removal and sequestration conducted in coastal and open ocean waters to:
A. Identify the most urgent unanswered scientific and technical questions, as well as questions surrounding governance, needed to: (I.) assess the benefits, risks, and potential scale for carbon dioxide removal and sequestration approaches; and (ii.) increase the viability of responsible carbon dioxide removal and sequestration;
B. Define the essential components of a research and development program and specific steps that would be required to answer these questions;
C. Estimate the costs and potential environmental impacts of such a research and development program to the extent possible in the timeframe of the study.
D. Recommend ways to implement such a research and development program that could be used by public or private organizations.
The carbon dioxide removal approaches to be examined include:
- Recovery of ocean and coastal ecosystems, including large marine organisms
- Iron, nitrogen or phosphorus fertilization
- Artificial upwelling and downwelling
- Electrochemical ocean CDR approaches
- Seaweed cultivation
- Ocean alkalinity enhancement.
Lest you get the mistaken impression that these proposals are being made by a bunch of wild-eyed radicals, the report makes it clear that carbon dioxide removal (CDR) is not a substitute for immediately eliminating fossil fuel use and curbing greenhouse gas pollution. It does not endorse any of the six strategies it considers or even advocate for CDR to be deployed. Instead, it outlines a 10-year, $1.1 billion research program that would fill in crucial knowledge gaps about each technology.
The Washington Post points out, “The idea of hacking the planet to counteract climate change — a practice called geoengineering — is controversial in environmental circles. Many activists worry that the distant promise of unproven technological fixes distracts people from the emissions cuts that need to happen today. Others point out that large scale interventions in the ocean, land, or atmosphere could have devastating unintended consequences — altering weather patterns or ocean currents, disrupting farms and fisheries, and contaminating the systems people and animals depend on to survive. The Earth is vast, complex and ancient, critics argue. It is the height of hubris for humans to think we can safely interfere with a system that has been evolving for more than 4 billion years.” [Emphasis added.]
Scott Doney, a marine scientist a the University of Virginia, is the lead author of this latest report. The Washington Post summarizes what he told them: “the toll of climate change is already staggering and greenhouse gas emissions are continuing to rise. There may come a time when averting catastrophic warming depends on sequestering carbon dioxide that has already been unleashed.”
“The goal is to have a research strategy that could inform societal decisions,” Doney says.
Yet many questions remain, Doney says. “Does it actually work? Does it store carbon for sufficiently long periods of time? What are the environmental impacts? How would you govern this? What are the dimensions of social acceptability?” Doney asks, “If you could slow climate change or stabilize climate at a lower warming level, is that worth the trade-offs of these deliberate changes to the ocean? These are things society needs to decide.”
The report recommends a code of conduct for ocean-based CDR research with stipulations that the experiments be tightly regulated and involve experts from Indigenous groups and other vulnerable communities. The scientists say the $125 million foundational research agenda must include surveys, legal analyses, and in-depth interviews with the people whose lives and livelihoods will be affected by the projects. Researchers must be willing to change course, Doney says, if their work turns out to be ineffective or dangerous, or if more powerful methods come to light.
Risks & Rewards
Holly Buck, a sociologist at the University at Buffalo and a contributor to the report, tells the Washington Post, any experiments should be “co-produced with communities.” Including locals in the design and deployment of projects will make them more equitable and could reveal insights scientists had never considered. Nevertheless, some climate activists think the risks outweigh any possible rewards.
A previous study by the National Academies found that humanity is unlikely to meet its most ambitious climate goal of limiting warming to 1.5° Celsius (2.7° Fahrenheit) without some form of carbon dioxide removal. By the middle of the century, people should be taking at least 10 gigatons of carbon out of the atmosphere every year — equal to roughly a quarter of current annual global emissions.
“This is the kind of deep dive we need,” says Kim Cobb, a climate scientist and oceanographer at the Georgia Institute of Technology who was not involved in the National Academies study. “It helps us to understand the potential benefits and downside risks and all the warts that you don’t get in the battles that are waged on op-ed pages.” In October, Cobb co-wrote an article for The Hill in which she argued geoengineering amounts to “playing dice with the planet.” She adds that fossil fuel companies often tout their investments in carbon dioxide removal as evidence of their commitment to climate action, even as they earn far more from the extraction and use of planet-warming fossil fuels.
Yet Cobb applauds the research strategy laid out in the National Academies report. “If we’re going to blunt that very large and well funded publicity campaign, we have to take those black box talking points out of the board rooms of big fossil fuel companies and into the public awareness in a way that is auditable and accountable and transparent,” she says.
Fertilizing The Ocean
The ocean already absorbs about a quarter of all carbon dioxide emitted by human activities, the report notes. Restoring crucial ecosystems to their pre-industrial state could boost their carbon dioxide uptake and deliver a host of other benefits, such as providing habitat for endangered species and protecting fisheries people depend on for food. Our own Michael Barnard sees some hope in geoengineering the ocean.
One ocean-based CDR strategy is known as “ocean fertilization,” which involves sprinkling the surface of the ocean with iron or phosphorous, which could promote the growth of photosynthetic plankton that convert carbon dioxide into food. In theory, the plankton would be consumed by other animals and the carbon they contain would eventually end up on the seafloor when the animals defecate or die.
But researchers haven’t firmly established that ocean fertilization actually results in lasting carbon removal. And it may have a nasty side effect. It could lead to toxic algae blooms that deplete the sea surface of oxygen and lead to massive die offs of marine animals. Since 2008, the United Nations Convention on Biological Diversity has barred ocean fertilization projects in international waters.
Other proposed tactics for storing carbon in the ocean have never been tested on a large scale in the real world. Among them are the idea of artificial upwelling — pumping cold, nutrient-rich water from the deep ocean to the surface, where it would in turn promote the growth of phytoplankton. There is also an idea floating around [no pun intended] that would use electricity to change the chemistry of sea water.
The ramifications of such projects could be profound, Kim Cobb says. The mere fact that scientists are considering them indicates how much of a challenge climate change poses for the human race, “We’ve already been using the ocean as a dumping ground of carbon dioxide and heat,” Cobb says. “If we can intervene with science based approaches that recognize the co-benefits and have a clear eyed view of the risks, then yes, I think we should be considering those. That’s my stance on the dismal state of where we are.”
Is there nothing that can be done to reduce the amount of carbon dioxide and methane in the atmosphere and the oceans? Yes, in fact there is, and it’s incredibly simple. Let me share the secret with you. Come close. Closer. Ready?
Stop Burning Fossil Fuels!