The Best Flavor of Geoengineering Stills Leaves a Bad Taste

By Jeremy Jacquot | July 26, 2010 8:28 am

The Eyjafjallajökull eruption as seen by NASA’s Terra satellite

In theory, geoengineering seems like the ideal remedy for our climate ills. Some white reflective roofs here, a little ocean fertilization there, a few simulated volcanic eruptions, and voilà! you have a potential fix for one of the world’s most intractable problems.

But there’s good reason to believe that many of these proposed schemes would prove much costlier to the planet over both the short- and long-term than more mainstream approaches to addressing climate change—and leave a number of critical problems, like ocean acidification, in the lurch.

Take the injection of sulfate aerosol particles into the stratosphere, which I alluded to earlier. The idea would be to recreate the cooling effects of a volcanic eruption by blanketing the sky with a thin layer of particles that would reflect a fraction of incoming sunlight back into space. For this method to put a crimp on greenhouse warming, studies estimate that it would have to cut solar radiation by roughly 1.8 percent—not an easy feat by any means, but not entirely out of the question either.

In addition to being (relatively) cheap, costing around several billion dollars a year according to some projections, stratospheric geoengineering would actually be doable. In a recent paper, Alan Robock of Rutgers University and his colleagues suggested that it could be done by sending fleets of military planes to dump large quantities of sulfur gas into the lower stratosphere several times a year. While it all sounds good on paper, it’s worth emphasizing, as if it wasn’t obvious already, that much of this is still highly speculative. The rapidly changing nature of climate models, from which most of these findings are drawn, also makes it inherently difficult to predict with any uncertainty what this scheme’s exact outcome will be. What is certain, however, is that it would have a fair number of unintended consequences—almost all of which would be bad.

According to a new paper in Nature Geoscience, stratospheric geoengineering, or “solar-radiation management,” as the authors refer to it, would affect different parts of the world differentially (go figure), helping to cool down some countries while cooking others. It would deal a particularly harsh blow to many parts of Africa and Asia, disrupting rainfall and storm patterns and fomenting drought-like conditions. The particles would also spur the destruction of the already vulnerable ozone layer, hindering the recovery of the Antarctic ozone hole and blasting a few new ones.

To compound matters, the cooling effects would be short-lived—a few years at best—and many of the problems would only become worse with time. In other words, it’s mostly a lose-lose situation: stop short and you lose the benefits; keep going and you continue to dig yourself into a hole. It shouldn’t come as too much of a surprise then that the authors’ main takeaways are that: 1) regional geoengineering isn’t such a great idea and that 2) reaching any sort of agreement on the “right” amount of geoengineering needed will be, shall we say, tricky.

But what is the alternative? Sure, there are a number of other proposed methods on the docket, ranging from solar shields in space (I kid you not) to carbon dioxide-sucking artificial trees, but most researchers would point to stratospheric geoengineering as being the one with the most promise. Which isn’t exactly encouraging. Of course, very few scientists are genuinely enthusiastic about the prospects of unleashing geoengineering unto the world. Most would argue that much more research is needed before we can engage in a serious conversation about relying on it and, even then, it should only be deployed in conjunction with other time-tested mitigation strategies.

Given the global community’s sluggish, half-hearted response to climate change, it is unfortunately probably only a matter of time before a few governments decide to take matters into their own hands. And, if anything, I can easily imagine some variant of these techniques being eventually used to “terraform” (i.e. make more Earth-like) Mars and other currently inhospitable planets—think Star Trek II’s Genesis device but much slower and less cool and advanced. That is, unless an alien race gets to us first and reverse-terraforms our planet like in The War of the Worlds.

Image: NASA

CATEGORIZED UNDER: Apocalypse, Biology, Geology, Politics

Comments (10)

  1. I’m normally the first guy to rock the science answer to a problem, but it seems like Geo-engineering will at best, put us behind the problem, and at worst, lead to dramatic unforeseen consequences. I hate to go too hippie on you all, but maybe we should just try and back off the destruction now.

  2. Georg

    “….as if it wasn’t obvious already, that much of this is still highly speculative. The rapidly changing nature of climate models, from which most of these findings are drawn, also makes it inherently difficult to predict with any uncertainty what this scheme’s exact outcome will be.”
    Strange, You never mention those “rapid changes” when defending climate

  3. Liz

    Geoengineering is scary – it reminds me of introduced species (like Kudzu) that cause unforeseen and often disastrous consequences. Let’s hope we don’t go there…

  4. Paul D.

    Geoengineering isn’t the solution to global warming, any more than sprinkler systems are the solution to building fires. But sprinklers get installed anyway, since we’re better off having them. We’re better off understanding how to use ham-fisted techniques to forcibly cool the planet as well, even if they are just a last resort if prevention fails.

  5. Liz

    Weather modification has not been highly successful even on a small scale. Why do we think we can modify the climate of the entire planet? Humans might think they can control Mother Nature but she will have the last laugh…

  6. Ocean acidification and warming are already killing life in the sea, which, aside from providing food for hundreds of millions of people, also creates most of the oxygen we need to breathe.

    Unmentioned in the article is the little problem of the “other” greenhouse gases we emit when burning fossil and biofuels. Even if we could manage (haha) to successfully contain the problem of heating from CO2, the ecosystem will collapse because ozone and acid rain from nitrous oxides, sulphur dioxides, and acetaldehyde are toxic to vegetation. Trees are rapidly dying all over the globe from the inexorably rising levels of tropospheric ozone. Crops are failing from direct foliar damage interfering with photosynthesis, and soils depleted of essential nutrients after decades of acidic precipitation.

    All forms of plant life that produce chlorophyll, representing the bottom of the food chain, are diminishing. The biosphere is shrinking, and top predators cannot find sufficient prey. Humans are top predators.

    Fix that with geoengineering!

  7. Turboblocke

    Who’s going to take responsibility for geo-engineering? If we can’t get organised enough to stop burning fossil fuels, what makes you think we can organise global geo-engineering?

    And who pays when it goes wrong and weather patterns get disrupted? Every little incident could get blamed on it, which could lead to increased terrorism or even wars. We might even see people trying to sue if their BBQ gets rained off.

  8. There shouldn’t be a reason we can’t investigate things like this while still putting our full effort into preventative measures to the problem. Science has a big place in both. Researching geo-engineering methods does not mean that we think they are the best answer, or that we even plan on using them. These stories should not alarm people. No one is saying that we give up on stopping damage to the environment and will just fix it another way, but it is good to know about these methods in case they are needed eventually, or we find one that can reverse damage that is already done without the possibility of negative side effects. We may never understand all the effects our actions will have, but that doesn’t mean we should stop trying.

  9. John Blake

    The truth is that stratospheric geoengineering is already being practiced on a large scale . What we call ‘chemtrails’ have been identified to be releasing aluminium particles, barium, silicom and othet toxic substances onto the earth’s surface for at least the last 10 years. So why is there this talk about it being just a speculative idea?

  10. I reckon something really interesting about your web blog so I saved to bookmarks.


Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!


See More

Collapse bottom bar