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Owning the climate: Will geoengineering help combat climate change?

The views expressed are those of the author and are not necessarily those of Scientific American.

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Mt. Pinatubo volcano above paddy fields in the philippinesCOPENHAGEN—The controversy at this climate summit revolves around two simple issues: Who cuts? Who pays? Of course, climate change does not distinguish between a ton of carbon dioxide emitted from cutting down a peat forest in Indonesia versus a ton emitted as a result of burning coal in Germany. Therefore, a relatively new term is beginning to stir some controversy here in the Danish capital outside the direct negotations: geoengineering.

That’s in part because the "Conference of Parties" negotiations have taken so long. After 17 years, the basic issues remain to be addressed, and overall emissions have grown since 2000—the year enshrined in the United Nations Framework Convention on Climate Change treaty as the peak year of greenhouse gas emissions for the developed world (the U.S. signed this agreement). With little hope of reducing emissions in the near term—some scientists, such as geochemist Wally Broecker of Columbia University think we’ll be lucky to stop at concentrations of 550 parts per million in the atmosphere—more radical solutions are on offer: artificial, eternal volcanoes; using saltwater mist to increase cloud cover; even flotillas of mirrors in space.

"Geoengineering is plan B," says oceanographer John Shepherd of the U.K’s Royal Society of plans to deliberately tinker with the planet’s climate. "It’s not to be adopted unless absolutely necessary."

After all, "geoengineering is technically possible," Shepherd adds. But "in most cases, it’s still on the backs of envelopes and there are very many things to be concerned about, like environmental impacts."

It’s not just environmental impacts from filling the skies with sulfur dioxide to mimic the cooling impact of a massive volcanic eruption, like Mount Pinatubo in 1991, among other plans on offer. "This will have vast human rights implications, on self-determination, on the right to food," says Diana Bronson, program manager at the ETC Group. "We’re talking about technologies that would modify the entire planet."

And though building a sulfur dioxide smokestack to the stratosphere is an expensive proposition, there are simpler and cheaper ways to accomplish these ends, including dumping such particles from a helicopter. "It would take 10 Howitzers firing a shell a minute a year to get sulfates into the atmosphere," says Jason Blackstock, an analyst at the International Institute for Applied Systems Analysis. "Fifty to eighty countries in the world are capable of this."

Already, Russian scientist Yuri Izrael has begun to experiment and the Chinese routinely seed clouds to produce rain or snow. The Indians and Germans have conducted scientific testing of dumping iron in the ocean to attempt to promote algae growth and thus carbon sequestration.

"We aren’t going back to the climate we had before," says Jane Long, associate director for energy and environment at Lawrence Livermore National Laboratory. "We are going to be managing the environment, not just the climate but also hydrology, soils. We have to learn how to do that."

Of course, there are geoengineering options that are not as dangerous, such as mechanical devices to suck CO2 out of the air. Physicist Klaus Lackner of Columbia University and others are working on such devices and believe they could be accomplished for $300 per metric ton of CO2 removed. And others advocate restoring organic carbon to the soil in the form of so-called biochar (charcoal), which could sequester as much as 900 megatonnes of carbon over the next several decades.

But still questions of governance remain. For example, who will determine the appropriate level for CO2 concentrations in the atmosphere? Freezing Russians or sweltering island states? Who will control the global thermostat?

"Reducing emissions should remain the top priority for the foreseeable future," Shepherd says, "but serious research is needed rather than enthusiasts working in their spare time." Perhaps control of the world’s climate shouldn’t be trusted to basement tinkerers or scientists.

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  1. 1. dcary3133 9:59 pm 12/17/2009

    Here are a couple less expensive things to try first:

    1. Have all small countries commit to planting a million trees in the next five years. All larger countries can commit to 5-10 million in the same timeframe.

    2. Change our (US) tax laws to give incentives to having fewer children rather than having more babies. Would this be turned into an anti-religious war before any agreements were reached?

    3. (OK, more than a couple) Encourage all countries to make attempts to limit their populations, because if there were only half as many of us as there are, we wouldn’t be having these problems in the first place. We need to go forth and subtract, not multiply!

    Link to this
  2. 2. debu 10:48 pm 12/17/2009

    Please read my balloon inside balloon theory and theory of gravitoethertons to understand global warming . Our seas are becoming warmer due to more accumulation of heat at center of earth due to focus of gravitoethertons at the center of earth. We have to tap out heat from center of earth for production of electricity and Mr. R.S. Sharma chairman N.T.P.C agreed to apply his resources.

    Link to this
  3. 3. erichj 11:55 pm 12/18/2009

    Please don’t throw the Biochar baby out with Geo Engineering Snake Oil bath water.

    All political persuasions agree, building soil carbon is GOOD.
    To Hard bitten Farmers, wary of carbon regulations that only increase their costs, Building soil carbon is a savory bone, to do well while doing good.

    Biochar provides the tool powerful enough to cover Farming’s carbon foot print while lowering cost simultaneously.

    Another significant aspect of bichar is removal of BC aerosols by low cost ($3) Biomass cook stoves that produce char but no respiratory disease emissions. At Scale, replacing "Three Stone" stoves the health benefits would equal eradication of Malaria. and village level systems
    The Congo Basin Forest Fund (CBFF).recently funded The Biochar Fund $300K for these systems citing these priorities;
    (1) Hunger amongst the world’s poorest people, the subsistence farmers of Sub-Saharan Africa,
    (2) Deforestation resulting from a reliance on slash-and-burn farming,
    (3) Energy poverty and a lack of access to clean, renewable energy, and
    (4) Climate change.

    The Biochar Fund :
    Exceptional results from biochar experiment in Cameroon
    The broad smiles of 1500 subsistence farmers say it all ( that , and the size of the Biochar corn root balls )

    Mark my words; Given the potential for Laurens Rademaker’s programs to grow exponentially, only a short time lies between This man’s nomination for a Noble Prize.

    This authoritative PNAS article should cause the recent Royal Society Report to rethink their criticism of Biochar systems of Soil carbon sequestration;

    Reducing abrupt climate change risk using
    the Montreal Protocol and other regulatory
    actions to complement cuts in CO2 emissions

    There are dozens soil researchers on the subject now at USDA-ARS.
    and many studies at The up coming ASA-CSSA-SSSA joint meeting;

    Link to this
  4. 4. Christina_Jenny 5:19 am 12/19/2009

    Scientists are giving wonderful suggestions but really don’t know whether it will be feasible to implicate all over the world? I believe, "muons" (cosmic rays)are the greatest threat. Will scientists think of controlling these particles reaching our Earth?

    Link to this
  5. 5. listening 1:17 pm 01/2/2010

    Stable humus that nature produces increases cec both directly and indirectly while biochar increases cec only indirectly. since biochar depletes natures humus i;m siding with nature including Her no-till way of gardening. Biowaste is better used to produce humus via aerobic decomposition.for more info. see jim rich

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  6. 6. eco-steve 5:53 pm 04/12/2010

    There is a fully developed and economical technique to eliminate unwanted CO2 from the atmosphere : Biomass pyrolysis. Biomass absorbs CO2, and when it is pyrolysed it produces biochar and hydrogen, neither of which are pollutants. See

    Link to this
  7. 7. Mesuno 3:57 pm 11/14/2010

    There is a great book on geoengineering which I read recently – titled something like "how to cool the planet".

    One conclusion that was pretty clear was that geoengineering is going to happen, and to some extents already is. There are projects taking place to paint mountaintops white (altering albedo to reduce local temperatures and reduce glacier melt rates).

    Some geoengineering technologies are already within the grasp of some of the worlds mega wealthy individuals who are technically capable of instigating projects (not to mention a plethora of smaller nation states, some with dubious governances).

    Biochar often gets lumped in with the wilder geoengineering approaches, but is very different both in quality and scope than most others – essentially it addresses the root of the problem (increasing CO2 concentrations) while other projects such as spraying sulphur dioxide into the upper atmosphere address the symptoms. Stop "treating" with sulphur and the planet could rapidly under go heating, stop producing biochar and the exisiting benefits of reduced atmospheric carbon persist, along with improved soil fertility, agricultural runoff issues and improved soil health.

    Biochar is also a project that is out of the reach of unilateral action – no one person or political organisation will be able to produce enough, quickly enough, to alter the global climate balance. However if it was gradually incorporated into existing global agricultural systems the carbon cycle could be gently brought back into balance.

    I’ve been <a href="">making biochar</a> for my own garden and the results have been very promising. Soil fertility is improving and we had a bumper crop of beetroot this year.

    Link to this

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