After Gutenberg

Geo-engineers believe that humanity should consciously change the planet’s environment.

Lockergnome reports that researchers at Harvard University and Pennsylvania State University have invented a technology to reduce the accumulation of atmospheric carbon dioxide.

By electrochemically removing hydrochloric acid from the ocean and then neutralizing the acid by reaction with silicate (volcanic) rocks, the researchers say they can accelerate natural chemical weathering, permanently transferring CO2 from the atmosphere to the ocean. Unlike other ocean sequestration processes, the new technology does not further acidify the ocean and may be beneficial to coral reefs.

The innovative approach to tackling climate change is reported in the Nov. 7 issue of the journal Environmental Science and Technology by Kurt Zenz House, a Ph.D. candidate in Harvard’s Department of Earth and Planetary Sciences; Christopher H. House, associate professor of geosciences at Pennsylvania State University; Daniel P. Schrag, professor of earth and planetary sciences in Harvard’s Faculty of Arts and Sciences, professor of environmental science and engineering in Harvard’s School of Engineering and Applied Sciences, and director of the Harvard University Center for the Environment; and Michael J. Aziz, Gordon McKay Professor of Materials Science in Harvard’s School of Engineering and Applied Sciences.

“The technology involves selectively removing acid from the ocean in a way that might enable us to turn back the clock on global warming — removing CO2 directly from the atmosphere while simultaneously limiting the rate at which man-made CO2 emissions are acidifying the ocean,” Kurt Zenz House says. “Essentially, our technology dramatically accelerates a cleaning process that Nature herself uses for greenhouse gas accumulation.”

In natural silicate weathering, atmospheric carbon dioxide dissolves into fresh water, forming a weak carbonic acid. This acid is neutralized as rain water percolates through continental rocks, producing an alkaline solution of carbonate salts. The dissolution products eventually flow into the ocean, where the added alkalinity enables the ocean to hold the dissolved carbon instead of releasing it into the atmosphere. As weathering dissolves more continental rock, more carbon is permanently transferred from the atmosphere to the ocean and ultimately to the sediments.

“In the engineered weathering process we have found a way to swap the weak carbonic acid with a much stronger one (hydrochloric acid) and thus accelerate the pace to industrial rates,” Kurt Zenz House says. “To minimize the potential for adverse side effects on the environment we combine it with other chemical processes, the net result of which is identical to the natural weathering process. As a result, the ocean’s alkalinity would increase, enabling the uptake and storage of more atmospheric CO2 in the form of bicarbonate, the most plentiful and innocuous form of carbon already dissolved in the earth’s waters. That means we may be able to safely and permanently remove excess CO2 in a matter of decades rather than millennia.”

Unlike other climate engineering schemes that propose reflecting sunlight back into space to cool the planet, the weathering approach counteracts the continued ocean acidification that threatens coral reefs and their rich biological communities. Moreover, the process works equally well on all sources of CO2, including the two-thirds of human emissions that do not emanate from power plants, and could be run in remote locations and powered by stranded energy, such as geothermal and flared natural gas.

The team cautions, however, that while they believe their scheme for reducing global warming is achievable, implementation would be ambitious, costly, and would carry some environmental risks that require further study. Replicating natural weathering would involve building dozens of facilities, akin to large chlorine gas industrial plants, on coasts of volcanic rock.

“The least risky trajectory is to significantly cut our carbon dioxide emissions — but we may not be able to cut them rapidly enough to avoid unacceptable levels of climate change,” says Aziz. “If it looks like we’re not going to make it, the ‘House Process’ has the potential to let us rescind a portion of those emissions while mitigating some of the chemical impacts the excess CO2 will have on the oceans. It won’t be ready in time, though, if we wait until we’re sure we’ll need it before pursuing R&D on the technical and environmental issues involved.”

“There are some big impediments to overcome in implementing such a plan,” notes Emily Gertz for World Changing. Referring to a report in Environmental Science and Technology Online, she states:

It would cost at least $100 per ton CO2 removed if implemented using currently available technologies. Powering the electrochemical weathering process would itself create CO2, thus reducing the overall impact of the effort. And there might be localized pollution around the plants: “‘Around the plant you would get a very basic solution,’ which could contain chlorinated byproducts, House says. These byproducts could harm sea life locally.”

“Still, it’s great to see these ideas emerging,” she says, “clearly we’re going to need a suite of solutions of all sizes and scopes to slow down climate disruption.”

Green Car Congress also covered the report and the commentary was interesting. A favorite observation came from Zach: “My first thought on reading this was to think that Dr. Evil had moved into the climate change business. But the academic affiliation of the authors makes me not brush it off quite so quickly.”

Dr. Ernest Partridge is a consultant, writer and lecturer in the field of Environmental Ethics and Public Policy. He has taught Philosophy at the University of California, and in Utah, Colorado and Wisconsin. He publishes the website The Online Gadfly and co-edits the The Crisis Papers. He is at work on a book, Conscience of a Progressive.

Whoops! Sorry, wrong slide. The above is a BBC photo of Prostetnic Vogon Jeltz, not Professor Partridge.

Writing for The Independent (UK), Johann Hari’s noted in a column, entitled “The Last Green Taboo: Engineering the Planet,” that “geo-engineers believe man should consciously change the planet’s environment, using technology, to counter the effects of global warming.” For example, some scientists propose seeding the ocean with nutrients that would cause organisms such as plankton to absorb atmospheric carbon, which would then fall to the ocean floor, out of harm’s way. Other schemes might cool the earth by reflecting solar energy back into space.

Hari is opposed to such schemes. He writes “It is far smarter to try to stay close to the carefully balanced ecosystem that has evolved over millions of years than to cack-handedly engineer our own, with the extremely limited knowledge we have.”

Ernest Partridge takes issue with Hari’s skepticism.

While I understand and sympathize with Hari’s reluctance to fiddle with the planetary life-support system, I suspect that we might not have a choice in the matter. For, in plain fact, mankind has, since the onset of the industrial revolution, “change the planet’s environment, using technology…” (Indeed, homo sapiens and its predecessor hominids have altered planetary ecosystems over the past million years, following the invention of fire-making and stone weapons). We have already significantly “engineered the planet,” through urbanization, industrialized agriculture (i.e., use of pesticides, chemical fertilizers and monocultures), GMOs, and the consumption of fossil fuels, all of which have resulted in pollution, accelerating extinction, and, of course, climate change.

Treehugger reports on a general warming to the idea of geo-engineering and other unorthodox methods that might slow global warming ranging from seeding the stratosphere with aerosol particles to simulate the cooling effects of a volcano to seep sea and bedrock carbon sequestration.

Partridge describes some schemes mentioned by Johann Hari or others previously:

• The National Academy of Science has proposed the placement of 55,000 mirrors in the upper atmosphere, to reflect solar energy away from the planet. The scheme strikes me as somewhat Rube Goldbergish.

• Similarly, Nobelist Paul Crutzen suggests that adding sulphur to the atmosphere would increase cloud cover and thus albedo (reflectivity). But what other effects would result from this alteration of the chemistry of the atmosphere? Of all the scientists now alive, Crutzen is one of the most qualified to answer this question. Still, I wonder.

• Researchers have found that sprinkling iron on the ocean surface causes a “bloom” in plankton, which ingest carbon and then, when they die, cause the carbon to fall permanently to the ocean floor.

• Similarly, James Lovelock (the author of the “Gaia hypothesis”), proposes lifting nutrients from the bottom of the oceans which would also cause marine microorganisms to absorb carbon and then precipitate it to the ocean depths.

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Partridge had a couple of additional schemes come to my mind:

• I understand that sea kelp is among the fastest-growing plant species. Kelp might be cultivated and harvested in vast areas along the continental shelves, and then sequestered (with its component carbon) in abandoned mines and oil wells. Alternatively, it could be anaerobically digested, producing methane (a bio-fuel) and an organic fertilizer. (Fertilizers are now primarily derived from natural gas and petroleum – i.e., fossil fuels). The combustion products of methane are water and carbon dioxide, which seems to amount to no solution to the CO2 problem. However, it is now possible to capture CO2 at the point of combustion.

• If rain-making technology advances, it might be possible to increase snow cover in sparsely inhabited northern regions of Canada, Alaska, and Siberia. This could compensate for the loss of albedo from the shrinking arctic ice cap.

If and when some geniuses come up with schemes of global engineering that safely and effectively mitigate the climate emergency, they may not be among those listed above. However, in any case, one might suppose that the more the remedial project simulates and/or accelerates natural processes, the better. And a medley of activities would be better than massive investment in one or two projects. As with nature itself, redundancy is the key to stability.

It is just possible that the global community of scientists and technologists have the know-how, not to solve the climate change problem immediately, but to eventually find solutions. But this will require massive investment in research and development, and the international political will to provide these is feeble, at best, and in the United States, virtually absent. Corporate interests, their satellite “think-tank” apologists, and their purchased politicians, are all conspiring to postpone a planetary rescue effort. And time is our enemy.

So while I am an optimist as to possibilities, I am a pessimist as to probabilities.

Los Angeles Treehugger Jeremy Elton Jacquot is less parsimonious about the geo-engineering proposals.

RealClimate contributor Raymond Pierrehumberg called for a 10-year moratorium on any geo-engineering plan, cautioning his colleagues that further research should only serve as a supplement to efforts aimed at slashing greenhouse gas emissions. Let’s hope cooler heads prevail.

By and large, this blog would have to agree with the Green Car Congress crowd, “This thing could backfire!” Although, the entire discussion helps promote awareness of the impact of anthropogenic emissions. We shall give Engineer-Poet the last word on this… for the moment… “Geoengineering is only a palliative, and we have to address the greenhouse gas problem directly.”

For more about the approach, see “Scientists propose new geoengineering option: increasing ocean’s alkalinity to soak up more carbon dioxide“