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Why Geo-Engineering is a Debate Whose Time Has Gone
Alex Steffen, 21 Dec 07

With some regularity these days, I get calls from reporters wanting to know my thoughts about various schemes for attempting to use enormous technofixes -- vast space mirrors, mountains of iron filings dumped into the oceans, newly planted forests of trees gene-hacked to suck in more carbon dioxide, intentionally filling the atmosphere with sulfate pollution (creating a sort of artificial volcano), etc. -- to combat climate change. And, increasingly, my opinion has grown stronger: they're all dumb, dangerous ideas.

I generally believe we ought to keep an open mind about matters scientific, and I'm prepared still to be convinced that one or more of these ideas can work and work well. That said, as the evidence currently stands, I think the intelligent stance regarding debate on these matters is one of extreme skepticism.

First of all, geo-engineering is a lousy term. It implies the certainties of engineering. It makes profound alteration of the Earth's climate and biological systems sound as easy as building a bridge or tunnel or skyscraper, when the reality is that we don't know anywhere near enough about the impacts on systems we're talking about changing to be sure of the results of our meddling. The term "geo-experimentation" or "geo-gambling" might be more accurate.

What's more, geo-experimentation efforts seem to me to be the epitome of carbon blindness. For instance, it's been pointed out by many other, smarter people that sucking CO2 into the oceans will worsen ocean acidification, a potential catastrophic ecological problem. So serious is the threat that the IUCN's Kristina M Gjerde recently wrote:

"The oceans are complex, dynamic, unpredictable and already vulnerable to the effects of climate change and acidification. We need mechanisms that will build their resilience, not undermine it. ...We don't need quick fixes to this global problem that may, in the long-term, cause far more harm than good."

Expect similar objections to every proposal for geo-engineering, that doesn't adequately encompass a full understanding of the biological and social consequences, intended or unintended, of intervention. And most of these proposals seem likely to be nothing but huge demonstrations of the law of unintended consequences.

Indeed, the track record of massive-scale environmental interventions is not an encouraging one. From the damming rivers to fighting forest fires to eliminating pests, our efforts have frequently been revealed in hindsight to be so overrun with unintended consequences as to become full-blown disasters, often disasters worse than the original problems we set out to solve. And, in general, the cost of our errors has tended to increase with the magnitude of the attempted solution. The literature is absolutely chock-a-block with big failed schemes to control nature.

We already know how to stop climate change, and the downsides of a societal effort to change our land use, adopt clean energy, redesign for energy efficiency and tax waste are minimal, and probably out-weighed by the overall societal benefits. While much innovation remains needed, the challenge, we know, is primarily one of political will.

Governments which are incapable of mustering the political will to seriously reduce emissions are not to be trusted to make responsible decisions about mega-engineering projects at a planetary scale. The chances of getting it profoundly wrong -- through negligence or greed -- are just too great.

And the odds of even a well-intentioned and thoughtful program going prfoundly askew are great. In general, the larger the scale of the project, the greater the bureaucratic inertia (in both governments and corporations), the stronger the tendency to corruption and cooked results, and the larger the financial incentives of those involved. Most geo-experimentation schemes would require budgets in the tens or hundreds of billions of dollars. That sort of money tends to make people less willing to admit it when things go wrong... and with schemes like these, if things went wrong, they could go wrong in massive and unpredictable ways.

Geo-experimentation, in practice, might well most closely resemble the U.S. effort to build a national missile defense system (which has poured tens of billions of dollars down a rat hole of corruption and incompetence, destabilized existing non-proliferation efforts and produced nothing but a long string of failures). Imagine "Star Wars" applied to your climate and the ecosystems upon which you depend.

This is not a matter of being pro- or anti-technology. I'm about as pro-technology as it's possible to get without having tape on my glasses, and I think it's entirely reasonable to make the distinction between smart deployments of technology -- tools that are transparent in their agendas, collaborative and democratic in their benefits, and ultimately easy to reverse or modify -- and technologies (like nuclear power) which are centralized, secretive, expensive and essentially irreversible. History tells us we ought to respect these with a healthy suspicion, like a snake in the laundry hamper, and assume they're dangerous until they're proven safe.

We don't need geo-engineering. We already have a path forward out of climate chaos. Embracing a bright green future -- one which lives within ecological limits and offers real prosperity -- is completely within our grasp. Hacking the only planet we've got rather than simply changing the way we live shows a lack of judgment, to put it mildly. Innovation, enterprise and political courage make up a much more realistic plan than attempting some sort of planetary liposuction.

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Hi Alex,

An awful lot of serious scientists see the vital need to explore ways to artificially counteract the warming from our artificial (if unintended) amplification of the greenhouse effect. In essence, we're already doing it, they say.

So, at least as a backstop, they say (and this group includes the likes of Ralph Cicerone, the president of the National Academy of Sciences), why not include significant research along this path as part of a menu of responses to global warming -- including mitigation of emissions, adaptation to unavoidable change (and garden-variety climate threats), and a concerted quest for next-generation energy options?

More on this in our Energy Challenge series:

Happy 2008 all. -- Andy

Posted by: Andy Revkin on 21 Dec 07

Hi Alex,

An awful lot of serious scientists see the vital need to explore ways to artificially counteract the warming from our artificial (if unintended) amplification of the greenhouse effect. In essence, we're already doing it, they say.

So, at least as a backstop, they say (and this group includes the likes of Ralph Cicerone, the president of the National Academy of Sciences), why not include significant research along this path as part of a menu of responses to global warming -- including mitigation of emissions, adaptation to unavoidable change (and garden-variety climate threats), and a concerted quest for next-generation energy options?

More on this in our Energy Challenge series:

Happy 2008 all. -- Andy

Posted by: Andy Revkin on 21 Dec 07

Dear Alex:
There is no stupidity quite so stupid as
not being prepared for a disaster. Have you insured your house? And have you insured your climate?
Those fixes are not to save the idiots who are willing to keep pouring CO2 into the atmosphere. They are to save us all when
the world realizes suddenly that things have gone too far.
And we'd like to save you too!

Posted by: Nick Woolf on 21 Dec 07

Thanks for the comments!

Andy - my biggest problem with the backstop argument is that it encourages people to think there's a do-over if we screw up our response to climate chaos, when in fact, we don't have any proven response or remedy. I'd bet that a greater number of credible scientists doubt the workability of geo-engineering than embrace it.

Nick - of course, you're presuming that these techniques will actually work, without producing worse effects -- a presumption I don't find valid. It's not insurance if we're not sure it will work.

That said, I'm willing to be convinced.

Posted by: Alex Steffen on 21 Dec 07

Like it or not, the Geoengineering debate is just getting started. I agree it's a fundamentally bad idea, but above all else, we must not abstain from the debate, just because we think the ultimate outcome should be obvious. I was at the fall meeting of the American Geophysical Union in SF last week, and there was a session dedicated just to Geoengineering. That's probably at least part of why you're getting calls. Here's a summary of a recent Geoengineering workshop held at Harvard from Science Magazine and some general commentary from the RealClimate blog.

Posted by: Zane Selvans on 21 Dec 07

Alex, I agree with you most of the time. But to borrow a notion from the latest issue of Wired, the status quo of unchecked carbon emissions is already the biggest geoengineering experiment of all time, and we're in the test tube.

If I were you, I'd be a little more open to whatever might reverse the ill effects of our current experiment. I agree we need to be extremely careful and skeptical. But to rule out any technical fix to a problem with the future of humanity at stake would be foolhardy.

We must be prepared to use every means necessary to keep the Earth habitable. Of course the easiest way would be to stop C02 production immediately. Since that's not going to happen, all options for repairs to the climate need to stay on the table.

Posted by: BlackSun on 21 Dec 07

Two comments:

1. Having been involved in considering geoengineering for a few decades, and just given a talk on the research needs in the geoengineering area at a half day symposium at the Pontifical Academy of Sciences at the Vatican, what struck me in preparing the talk was how little has really been looked at regarding this issue (in the physical science complications, in likely impacts, in governance and legal issues, in moral and equity aspects, and even in possibilities for what could be done. For geoengineering to be considered an option (along with mitigation and adaptation) in any real sense, a lot of research and work needs to be done. And until that research is much further along and shows some plausible and workable options, this should be viewed as a research area, and not jumped up into discussion as a viable option that might allow less haste and seriousness in cutting emissions (which will be needed in any case for at least a couple of critical reasons: most geoengineering does nothing about ocean acidification, and if one does not cut emissions, then will be leaving an ever increasing commitment to geoengineering to future generations.

2. As a sort of related note, it is important to note that there are many possibilities encompassed under geoengineering--not just sulfate aerosols in the stratosphere. While most are thought of in terms of an alternative to such strict mitigation, others might more properly be thought of as relating to adaptation, or delaying or moderating particular impacts until mitigation can be effective, or being mainly a local or regional response, etc. and so may be appropriate because the world is already experiencing a lot of impacts. So, be careful about blanket statements (e.g., against all geoengineering)--definitions here are pretty hazy so one might well unintentionally rule out some interesting approaches).

So, indeed, geoengineering is not nearly ready to be given as a reason to slow mitigation, but with work, it might be able to contribute in some ways.

Mike MacCracken

Posted by: Mike MacCracken on 22 Dec 07

Thought provoking. I have three words for you: Bureau of Land Management. Pursuing all options is necessary given the scale of the problem. What scares me is who will execute on the scientific outcomes? Is there a Bureau of Earth Management around the corner? I hope hubris isn't the new green.

Posted by: Willie Brent on 22 Dec 07

Bottom line: while every effort in energy efficiency and conservation is welcome, very large scale clean renewable energy solutions have to be designed and build NOW:

This is where the M.A.R.E. Initiative comes in.

M.A.R.E. is put together by people who care about the future of this planet and want to act now, before it's way too late. People who do realize we need to think BIG.

M.A.R.E. is about putting our priorities right as a globally responsible civilization and it is about decisive leadership and bold visions.

MARE's goal is to become the largest independent clean energy provider in the world and has the potential to make the Difference, the next big step in our progress as a civilization.

The project is based on proven technologies, qualified as "suitable for funding" by the World Bank.

Posted by: MARE Initiative on 22 Dec 07

Alex, glad you wrote this, and for once I disagree with you; but then, you know this, as I've already written about my views on geo-engineering, here on Worldchanging.

If "tipping points" are for real, and it simply doesn't prove feasible to get the world moved off of carbon energy (while also keeping people fed and employed) quickly enough, then every humane solution that *is* feasible must be on the table for serious review, including the family of interventions called "geo-engineering". Not looking at such interventions could be the equivalent of the Viking settlers in Greenland, refusing to switch from wool and farming to sealskin and hunting despite the Inuit's living proof that these technologies were the only things that worked in that re-freezing climate. The Nordic cultural/ideological commitment to avoid certain technologies just doomed them.

Meanwhile, it's not a fair characterization of human history to say that our large-scale interventions into natural systems have always been disastrous. Environmental historians, as you know, now declare that many "wild" and "natural" landscapes are actually managed by humans, over multi-thousand-year timespans. There are quite a number of farming cultures that have survived thousands of successful, sustainable, uninterrupted years. Parts of the destroyed Aral Sea have come back to life with engineered intervention. The human track record may not be great, but we *are* learning, and we will be very motivated to learn if shading the earth a bit with injections into the atmosphere (or whatever) appear to be the only thing standing between us and massive disruptions in agriculture etc. (Significant disruptions are already happening, as you know.)

Finally, do we *know* that thinking about geo-engineering "encourages" giving up on carbon emissions reduction? This bromide is oft-repeated but I have never seen it substantiated in any meaningful way. I doubt very much that the impact of geo-engineering talk on emissions reduction over time is more than marginal. Advocacy and science voices will continue pushing harder and harder for reductions, as they should, and the world will still face this imperative, in any foreseeable future scenario, with or without geo-eng.

I understand your view here, especially as reversibility is such a huge worry. We could screw things up worse. But we could also save some things worth saving. The jury is far, far from in on this question, so I don't see the need for you or Worldchanging to join the chorus of anti-geo. No one is saying "start the pre-fab volcanos." But *not* to research the options for stabilizing possible runaway climate change would at this point be inethical.

Warm best for the holidays from warming Sweden,


Posted by: Alan AtKisson on 22 Dec 07

"they're all dumb, dangerous ideas"

Exactly. Thanks for publishing that. It shouldn't have to be pointed out of course, but for some it seems to be required.

What I'd add to that is that going by many reports and a great deal of evidence, if the mind-control and botched weather-engineering aspects of the 'Star Wars' programs are taken into account (such as with HAARP for example), then it comes as no suprise exactly why so many people have become so stupid so as to make those sorts of suggestions for dealing with climate problems.

The whole spectrum of where sane thoughts reside has been made inaccessible to their brains.

Posted by: zupakomputer on 23 Dec 07

Are we communicating as if we are living in a modern day Tower of Babel? Is our unbelievable failure to communicate reasonably and sensibly about whatsoever is somehow real, and to widely share adequate understandings regarding both how the family of humanity "fits" within the natural order of living things and what are the limitations of the planet we inhabit, in evidence here and now?

Perhaps the human community is indeed in a serious predicament, but only in part because of the objective biological and physical circumstances defining our distinctly human-driven predicament. The global challenges in the offing are further complicated by our incredible failure to communicate effectively about the potentially pernicious results derived from having recklessly grown a soon to become patently unsustainable, colossal global economy, one that we have artificially designed, conveniently constructed, and unrealistically expanded without regard for the requirements of biophysical reality.

Could it be that the current gigantic scale and unchecked growth rate of the global economy is unsustainably driving both per human over-consumption and unrestrained human population growth toward the point in human history when the willful, relentless, unregulated growth of consumption, production and propagation of the human species precipitates the collapse of Earth's ecology, even in these early years of Century XXI?

Steven Earl Salmony
AWAREness Campaign on The Human Population, established 2001

Posted by: Steve Salmony on 24 Dec 07

Dear Alex, Andy and Alan,

OUR contrived logic, linear thinking, material obsessiveness and mechanistic world view, that we see pervading the predominant culture on Earth in OUR time, could result in the children following OUR EXAMPLE and recklessly charging down a "primrose path" to be confronted by a colossal ecologic or economic wreckage, the likes of which only Ozymandias has seen.

What do you think?

Steven Earl Salmony
AWAREness Campaign on The Human Population

Posted by: Steve Salmony on 26 Dec 07

David Keith on

Up until seeing this talk, I shared pretty much the same view, but now I have changed my mind.
It seems to me we need to have the discussion about plan B now and understand it's dangers and consequences.



Posted by: Serge de Gheldere on 26 Dec 07

Dear Serge de Gheldere,

Thanks for your expressed capacity for experience and willingness to change your mind in the light of good scientific evidence. These attributes are so impressive and rare in our time, it appears.

From my humble perspective, humanity is in clear & present danger of losing the exquisite value to be found in one of God's gifts to humanity: the carefully and skillfully developed science on climate change.

Is it possible that the standards for determining what is real and true in our culture today are these: whatsoever is widely shared, consensually validated and judged to be ecomonically expedient, politically convenient, socially agreeable and religiously tolerated is true and real........... the biophysical conditions of the natural world notwithstanding?

At least to me, it seems that good science is ignored, countless distractions presented or else silence allowed to prevail whenever reasonable and sensible evidence comes into conflict with what culture prescribes as real and true. Perhaps science does present culture with evidence of inconvenient truths.

Steven Earl Salmony, Ph.D., M.P.A.
AWAREness Campaign on The Human Population, established 2001

Posted by: Steven Earl Salmony, Ph.D., M.P.A. on 27 Dec 07

I've reluctantly concluded that we need to consider geo-engineering as one tool in the toolkit . It's not the most important tool, nor is it capable of doing the job alone - but we probably won't be able to do the whole job without it.

The question becomes, what kind of geo-engineering? What has few risks and many promises? We might consider things that would be good to do anyway. For example, there are many benefits, including substantial carbon sequestration, by increasing organic matter in agricultural soils. It makes sense anyway to halt deforestation and to help biomes recover. It seems like a good idea to greatly increase our use of tree crops. Wetlands restoration is a good idea even if you don't need to sequester carbon. And so on.

Perhaps the term "geo-gardening" would make more sense?

It still seems most important of all to radically increase the efficiency with which we use energy - more bang for the buck, faster, than anything else we can try - and also a good idea even without a climate crisis.

Posted by: David Foley on 27 Dec 07

There is a moral hazard in even considering geoengineering. And it may well turn out that geoengineering will never be necessary to our survival or unfeasible.

Personaly I don't know if any kind of geoengineering will ever be practical or not and I'm skeptical of anyone who makes a claim one way or another. I'm a fan of Worldchanging but this post seems to lower the level of debate on this issue rather than elevate it.

If anyone's interested in a non-partisan out of the box look at the pros and cons of geoengineering I encourage you to check out David Keith's Ted Talk on the subject which you can watch at:

One last quibble you mention "We already know how to stop climate change". While I agree that we should go carbon free it's worth stressing that this doesn't stop Climate Change. Not unless you believe that all the excess CO2 we've been pumping into the atmosphere will suddenly fall out of the sky on the day we go carbon free. Cutting carbon emissions is analagous to taking our collective feet off the accelerator, it shouldn't be confused with breaking.

Posted by: Jose on 28 Dec 07

Dear Jose and David Foley,

Perhaps we begin now by following Jose's advice and taking our collective feet off the accelerator. That would be one good thing to do. I doubt people would deny the need to immediately implement such a proposal, unless, of course, they are blindly and adamantly committed to the seemingly endless expansion of the soon to become (as currently organized and operated) unsustainable global economy, come what may.

Of course, there are many other, likely necessary changes in human behavior in the offing.

As you have put it, David, using energy more efficiently looks like a no-brainer.



Posted by: Steven Earl Salmony, Ph.D., M.P.A. on 28 Dec 07

If the human species is rapidly “growing” an ecological debt, as we rampantly dissipate Earth’s limited resources faster than the planet can restore them for human benefit, does it not appear evident that some consideration and much open discussion could reasonably and sensibly focus on strategies for limiting the unbridled increase of per human over-consumption of natural resources?

Posted by: stevenearlsalmony on 28 Dec 07

What are we going to say to our children when they ask us the two following questions?

Question One:

When did you know your generation was foolhardy and selfish, inadvertently precipitating the massive extinction of life as we know it and ravaging the Earth?

Question Two:

Why did you and your leaders not stop what you were doing and at least try to do something different, that might have given life as we know it a chance for a good enough future rather than keep charging ahead down the “primrose path” of endless human over-growth activities, the ones you could see would lead humankind to confront some kind of colossal wreckage, the likes of which only Ozymandias has seen?



Steven Earl Salmony
AWAREness Campaign on The Human Population, established 2001

Posted by: stevenearlsalmony on 29 Dec 07

Please understand that I am concerned my generation of elders could be "selling a bill of goods" to our young people today; but we have no intention of fulfilling our promises and will fail to deliver the goods. In part, these unfortunate circumstances result from my generation's unbridled over-consumption of Earth's finite capacity to sustain life as well as from our reckless and unrestrained dissipation of limited natural resources bound up in the huge scale and growth rate of economic globalization.

My not-so-great generation appears to be mortgaging and threatening the future of its children by remaining religiously focused upon the endless accumulation of material wealth, the unchecked increase in per capita consumption of scarce resources, and the continuous consolidation of political power used to conquer Earth. Despite all our high-minded rhetoric to the contrary, we need not look far to see that money, power and privilege for ourselves, for our bought-and-paid-for politicians, and for our newly-made rich minions in the mass media are the primary object of our desire. Regardless of the human-driven calamities that might befall coming generations, the leadership in my generation advises us to live long, and live large, in a patently unsustainable world of idle comforts, effortless ease, conspicuous consumption, secret handshakes, exclusive clubs, exotic hideaways and thousands of private jets, having abandoned our regard for the less fortunate among us, for the maintenance of life as we know it, and for the preservation of the integrity of Earth. Please, now, recognize the single-minded pursuit of dollars, political power and privileges to profligately consume, and to magnificently ignore the practical requirements of biophysical reality, as our raison d'etre, come what may for the children.

When my not-so-great generation completes its unsavory 'mission' on Earth, I fear young people will look back in anger and utter disbelief at the things we have done and failed to do.....all things we proclaim loudly now as evidence of our many virtues.

Yes, of course, there is an ecological debt.... but, please, let us get real for a moment and understand what my generation does not want its children to know: your elders are determined to let the ecological debt and looming threats to human and environmental health, for which we are clearly responsible, fall into your lap, come what may.



Steven Earl Salmony
AWAREness Campaign on The Human Population, established 2001

Posted by: stevenearlsalmony on 30 Dec 07

Dear Friends,

Perhaps we can agree that global challenges, already visible on the far horizon, could soon be posed to humanity. Because economic globalization could be approaching a point in human history when it becomes patently unsustainable on a planet with the relatively small size and make-up of Earth, the current scale and unbridled growth of global consumption/production/propagation activities of the human species could produce a colossal wreckage of either the global economy or Earth's ecology, even in these early years of Century XXI.

If leaders are presented with a forced choice between protecting the global economy and preserving Earth's ecology, it seems crystal clear to me that the leadership of the kind we have today will reflexively choose the economy.....first, last and always.

What do you think?



Steve Salmony
AWAREness Campaign on The Human Population, established 2001

Posted by: stevenearlsalmony on 5 Jan 08

Overshooting Earth's carrying capacity and what is to be done now.
The human species appears to be in an "overshoot" situation relative to Earth's limited capacity to sustain life as we know it much longer.

In the course of history, I cannot find any evidence of a single species other than the human species that has precipitated such multi-faceted leviathan-like circumstances.

Inasmuch as human beings possess the attributes required to have induced the gigantic problem we see looming ominously before humanity in the offing, it seems to me that we also maintain the capabilities to take the measure of the problem, however colossal, and find a solution to it, one that is consonant with universally shared values.

Understanding population mathematics (i.e., the exponential function) and human creatureliness would make a big and helpful difference. Appreciating the limits of linear thinking will be another giant step forward.

Once we share an adequate enough understanding of the global problem of huge proportions, then it will become possible for the family of humanity to carefully and skillfully find a humane path toward a sustainable future, I believe.

Steven Earl Salmony
AWAREness Campaign on The Human Population, established 2001

Posted by: stevenearlsalmony on 5 Jan 08



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