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Earth: Under Repair, Forever

Geoengineering sounds like something from a science fiction novel, but we actually do it every day

The term geoengineering is relatively new. It follows and alters the word terraforming, coined by a science fiction writer 70 years ago to denote the act of making another planet more Earth-like. When I was writing my own Mars trilogy of novels in the 1990s, I described the deliberate alteration of that planet to give it an Earth-like biosphere; as I did so, it occurred to me that we were already doing to Earth what my characters were doing to Mars.

But to say that we were "terraforming Earth" was painfully ironic, suggesting as it did that we had damaged our home planet so badly we now needed to take drastic steps to restore it to itself. When geoengineering entered the lexicon, many bristled at the word's hubristic implication that we had the knowledge and power to engineer anything so large and complex as our planet. Still, the term has stuck, and it has essentially come to mean doing anything technological, on a global scale, to reduce or reverse the effects of climate change.

Defined this way, the idea makes almost everyone uneasy -- including the scientists who introduced it, most of whom agree that the best solution to our climate problem remains rapid decarbonization. But these scientists have also noticed that our progress on this front hasn't been good. We lack the political mechanisms, or maybe even the political will, to decarbonize. So people are right to be worried, and some of them have therefore put forth various geoengineering plans as possible emergency measures: problematic, but better than nothing.

Objections to geoengineering appeared immediately. Many people have expressed doubt that the proposals would work, or believe that a string of negative unintended consequences could follow. Merely discussing these ideas, it has been said, risks giving us the false hope of a "silver bullet" solution to climate change in the near future -- thus reducing the pressure to stem carbon emissions here and now.

from NRDC Going Underground

There has been much debate recently about certain carbon sequestration proposals, which some people regard as geoengineering. Which ones are scientists most intrigued by?

Carbon sequestration can include a range of activities, but it most commonly refers to the geologic sequestration of carbon dioxide, whereby the gas is captured at a source (such as a power plant) and injected into subsurface rock formations. When this is done at carefully selected and properly operated sites, the carbon dioxide can be stored underground permanently. Some people might well place this in the category of geoengineering, but at NRDC we view it as a much more established technology than the term connotes. In fact, this type of activity simply mimics natural geologic processes; the main difference is that in this case, the process is sped up so that it occurs over tens rather than millions of years. The CO2 is trapped both physically (in the pore spaces of the rocks) and chemically (by reacting with subsurface rocks and fluids to form new minerals). Unlike other, more experimental geoengineering schemes, geologic carbon sequestration is an important tool that can be used right now to help curb climate change.

-- Briana Mordick, an oil and gas science fellow based in Washington, D.C.

These are valid concerns, but the fact remains: our current technologies are already geoengineering the planet -- albeit accidentally and negatively. Consider that significant percentages of the world's wetlands have been drained, and large swaths of its forests cut down. Ecosystems have been devastated by overdevelopment. We've raised atmospheric CO2 levels by about 100 parts per million, and average global temperatures have gone up accordingly. Our oceans have soaked up so much of the carbon we've dumped into the atmosphere that the seas have measurably acidified. On land, hundreds of species have gone extinct. And far worse damage is sure to follow if this inadvertent geoengineering campaign of ours is allowed to continue.

For the rest of history, we will be required to work at repairing the damage we've already done to the biosphere. Geoengineering, then, has become our ongoing responsibility to life on this planet, including all human generations to come. All of which leads to the question: can we actually design and accomplish any geoengineering projects that would mitigate or reverse climate change? Putting aside issues of political capability, are any of these projects physically possible?

The answer appears to be: yes, some of them are. Maybe.

Some of the most talked-about proposals entail removing CO2 from the atmosphere, or not letting it enter in the first place. One of them calls for trapping it and storing it deep underground. The concept behind carbon capture and sequestration has already been demonstrated to work; many scientists think it merits further study. And to those who say our most urgent goal is holding atmospheric carbon levels as close as possible to 350 parts per million, it's attractive for obvious reasons.

Another oft-discussed idea involves shooting sulfur dioxide particles into the upper atmosphere in order to reflect incoming sunlight back into space. While this, too, would appear plausible from a mechanical standpoint, the veneer of plausibility only adds to serious concerns about unknown secondary effects, as well as worries that by taking an action such as this one, the root issue -- our need to curb carbon emissions -- would remain unaddressed. As a result, this is one of the most controversial geoengineering plans to date. It practically glows with the hubris of weird science; it scares people.

When ideas move from the atmosphere to the ocean, they get even scarier. One of the most hotly debated sequestration plans would have us dumping iron dust into the ocean to promote algal blooms, which would eventually sink, taking their carbon load with them. Last July a California entrepreneur and geoengineering advocate tried doing this off the coast of British Columbia -- and found himself in trouble with Canada's environmental ministry, the U.S. National Oceanic and Atmospheric Administration, and the broader scientific community.

Among their concerns is that actions like his could disturb the ocean's nutrient balance and food chains. But they also worry about accelerating ocean acidification -- a problem for which there exists no geoengineering solution. Some have proposed dumping pulverized limestone into the ocean to neutralize its acid; the United Kingdom's Royal Society, however, has concluded that the amount required would be equal to the White Cliffs of Dover, and then some. This is a fine addition to the parade of images that feature prominently in the eco-disaster subgenre of British science fiction, and it reminds us of an important lesson: we simply don't have the power to reverse all that we've done.

So geoengineering the atmosphere looks iffy at best; geoengineering the oceans even worse. What about the land? We've been altering our landscapes for thousands of years, of course, so there's ample "proof of concept." But just as technology has aided us in the task of deforesting and draining our wetlands, so too does it now provide us with the capability to do things like reforest and rehydrate. Thinking about such potential reversals makes me believe the definition of geoengineering should be broadened. Our actions have a global impact; it's good to be reminded of this by giving that impact a name. Were we to take up hybrids and electric cars in great numbers, for example, could that be considered geoengineering? Under an expanded definition, absolutely. Whatever we do as a civilization of seven billion is inevitably going to have a geoengineering effect.

What about that number, seven billion? Could stabilizing our population count? Again, yes. And we know of one good way to achieve this goal: promoting women's legal and social rights. Wherever they expand, population growth shifts toward the replacement rate. This particular geoengineering technology nicely illustrates how the word technology can't be defined simply as machinery; it includes things like software, organizational systems, laws, writing, and even public policy.

Were we to change our lifestyles in order to conserve resources, could that be thought of as geoengineering? Consider the example of Zurich, which is hoping to become a 2,000 Watt Society. The city government is embarking on a grand experiment, encouraging citizens to live on an average requirement of 2,000 watts of electricity per person -- what each of us would have were the world's electricity distributed equally. (Right now Americans average more than 10,000 watts, Bangladeshis about 200.) Zurichers who have participated report no diminishment in their quality of life; on the contrary, they say that their lives have been augmented by new feelings of accomplishment and virtue.

As a science fiction novelist trying to write the realism of the twenty-first century, I'm convinced that these broader definitions of geoengineering better describe what we'll all be doing in decades to come. In my books I've imagined people salting the Gulf Stream, damming the glaciers sliding off the Greenland ice cap, pumping ocean water into the dry basins of the Sahara and Asia to create salt seas, pumping melted ice from Antarctica north to provide freshwater, genetically engineering bacteria to sequester more carbon in the roots of trees, raising Florida 30 feet to get it back above water, and (hardest of all) comprehensively changing capitalism.

These fictional methods range from promising to risky to crazy. All of them make for interesting stories, I hope -- and also compel us to think about what we can do to help Earth's biosphere, both individually and collectively. We have many opportunities to act; those actions scale up. If we take advantage of the opportunties, we'll be creating a permaculture that works in balance with our planet over the long haul. We'll all be geoengineers -- without ever even having to try any of the more dangerous experiments we now think of when we come across that word.

FROM THE EDITORS: A previous version of this story noted that organizers of the 2,000 Watt Society experiment encourage individual participants "to live on 2,000 watts of electricity per person, per year," and also that "Americans average more than 10,000 watts a year." In fact, both the 2,000-watt goal and the 10,000-watt measurement represent average, continuous -- rather than yearly -- figures. The new version of this story reflects these changes.

image of Kim Stanley Robinson
Kim Stanley Robinson is a Hugo and Nebula award-winning science fiction writer best known for the best-selling Mars trilogy. His work often delves into ecological and sociological themes.
Great article, Stan. One quibble: in the antepenultimate paragraph, the phrase "2000 watts per year" is pretty clearly inaccurate: it should probably be either "an average of 2000 watts" or "2000 watt-years per year." Easily corrected.
Believe it or not, Tom. Of course it is "a great article". But I should like much better practical advice to improve the Planet's condition. Here again the facts, not too much blown up scientifically, but simplified to the truth: About 70% of the Globe is corvered by sea. The 30% mainland would be as dry as the centre of the desert Sahara, if there would not be 'the steam engine' TROPOSHERE. From the sea surface evaporates water. Most of it -- up to 80% -- comes down already at sea again. But the rest is distributed accross the continents. By the way: Very differently. Or very unjust. Now comes the simple truth. Climate-Engineering is switched on due to responsibility of mankind, being a partner of the Creator. The evaporation process is easily to be improved from the edges of the hot and dry coast lines in North Africa and Middle East at times, when the winds are blowing land inwards. More details from JotFried(at)
Yeah, that para about the 2,000-Watt Society is not quite right. The Watt is a unit of power, i.e. energy per unit of time. The 2000-Watt Society is trying to get Western Europeans and Americans to live on an average of 2000 Watts. Over a year, that would come to just over 17,000 kilowatt-hours, or if you prefer SI-derived units, 63 GigaJoule. Still, this is a minor blemish of interest only to the very geekiest of science geeks.
Dumping iron dust into the ocean to promote algal blooms, which would eventually sink, taking their carbon load with them” doesn’t seem like “geoengineering” (a variation of terraforming), if by terraforming one means to change the nature of a planet so much that it becomes like another planet (as with Mars becoming more Earth-like such that it can support human life). Even on a large scale, tweaking the carbon content of Earth’s atmosphere seems too trivial to serve as a good example of terraforming, especially since it mimics existing natural processes. And completely useless if “global warming” turns out to be part of a natural cycle, as many argue. Schemes to terraform Mars wouldn’t simply speed up existing processes but disrupt them entirely, or be undone by naturally occurring circumstances, which is why they’re so controversial. True terraforming has never been done before and is, despite your argument, science fiction. The point of engineering is to create some specific effect, based on scientific principles, not hope for some inadvertent effect, which would be an entirely different thing, and not how scientists or engineers work. I therefore don't think geoengineering should be used to describe the inadvertent consequences of human life, and would argue that use of “terraforming” should be restricted to examples that substantially change the nature of an entire planet such as to support human life -- although, in science fiction, you might be able to get away with straying from this using artistic license, but it would probably further confuse the line between science fiction and science fact.
Geoengineering is a mechanistic solution to a complex systems problem. It is heroic and, excuse me, big swinging dick technology that will, in all probability, create more problems than it solves. We need to stop thinking like hammers and begin thinking like trees or rivers, flowers or mountains. The fact is there are ecological solutions to climate change that are much more promising with fewer side effects that could be discussed and aren't because geoengineering dominates the conversation. Look at two winners of the Buckminster Fuller Challenge, John Todd's proposal for the remediation of coal-ravaged lands in Appalachia and Allan Savory's system of holistic management which uses herd animals to improve the land and reverse desertification while providing a living for pastoral people. Back in the 1990s, there was at least one conference on "geotherapy" which applied ecological design to environmental problems. Would be good if we applied ecological design on a geoengineering scale now. If you really want to get down to it, adopt the recommendations of the UNEP in last year's Near-term Climate Protection and Clean Air Benefits: Actions for Controlling Short-Lived Climate Forcers ( Here is a practical plan to reduce the expected temperature rise by half by 2050. Unfortunately, it isn't heroic technology. It's replacing three stone cooking with more efficient stoves to reduce black carbon, cleaning up diesel engines to reduce tropospheric ozone, and plugging up methane leaks - housekeeping. But housekeeping writ large is what ecological practice is. One of the advantages of this approach is that black carbon and tropospheric ozone are resident in the atmosphere for only a few weeks. There is a nearly immediate effect, locally and globally. Another advantage is that reducing these pollutants pays for itself in ancillary benefits and reduced operating costs as well, thus removing the "who pays" question from consideration. I wonder why we aren't talking about this instead of space umbrellas and giant hoses to inject sulphur into the stratosphere. Lots we can do to slow and adapt to climate change but geoengineering is a distraction not a practical solution.
Sulfur dioxide is a gas, so I don't know what you mean by shooting _particles_ of it into the upper atmosphere. a gas would have no solid surface to reflect light off of. In any event, injecting sulfur dioxide into the atmosphere sounds like a disaster waiting to happen. SO2 is a major contributor to acid rain. Unintended consequences, indeed!