Terraforming Earth is the effort to use large-scale engineering to affect geophysical processes in a way to avert radical changes to the environment -- that is, to make Earth "Earth-like" again. I touched on the idea first here, expanded on it here, and explored some of the more philosophical questions here. In all of these pieces, however, you'll note that this terraforming work is thought to be an option for some time down the road, after other solutions are exhausted. There's no argument in those three essays that we should start large scale engineering efforts now.
Today's email brought news that should make us think hard about how soon we might want to bring such efforts to bear.
Many of you sent me links to the article in today's Guardian UK newspaper (linking to a New Scientist article) outlining a "tipping point" in the Siberian arctic: the permafrost appears to be melting. This is happening due to a combination of natural arctic temperature cycles, global warming (Siberia is warming faster than any other place on Earth), and a feedback effect from melting snow -- the darker ground absorbs more heat, resulting in faster melting of adjacent permafrost. Siberian permafrost covers a million square kilometers of ground that's largely peat bog; the peat has been producing methane for centuries, but that methane has been trapped under the permafrost. With the permafrost melting, the methane would be released into the atmosphere, accelerating global warming by a substantial amount. How quickly the methane would be released remains an open question -- would it take years to release it all? Decades? A century or more? Clearly, this situation demands a great deal more study.
It's important to note that the source of this story is not a peer-reviewed, multiply-confirmed piece of research in Nature, Science or the PNAS. It's an article in New Scientist about a presentation from a group of researchers just back from Siberia. This doesn't mean that the findings are wrong, only that we should be skeptical until they've been confirmed. But that such permafrost melting would result in the release of abundant methane is not a new theory, and New Scientist notes that independent research points to methane "hot spots" already forming in the region.
For the moment, then, let's assume that the article is generally correct: the permafrost melt is getting faster, and the boggy ground beneath is releasing its pent-up methane. There are two important things to know about this situation: the amount of methane that would be released is projected to be in the multi-gigaton range -- one source says 70 billion tons, another says "several hundred" billion tons; and methane is 21 times more powerful a greenhouse gas than carbon dioxide. In essence, the release of (say) 100 billion tons of methane would be the functional heat-trapping equivalent of 2.1 trillion tons of CO2. To put that number into perspective, the total annual output of greenhouse gases from the US is about 7 billion tons of CO2 equivalent.
This is a big deal.
But there's actually a third important thing to know: although CO2 takes upwards of a century to cycle out of the atmosphere naturally, methane (CH4) takes only about ten years. Why the difference? Chemical processes in the atmosphere break down CH4 (in combination with oxygen) into CO2+H2O -- carbon dioxide and water. In addition, certain bacteria -- known as methanotrophs -- actually consume methane, with the same chemical results. These processes have their limits, however; an abundance of methane in the atmosphere can overwhelm the oxidation chemistry, making the methane stick around for longer than the typical 8-10 years, and the commonplace methanotrophic bacteria evolved in an environment where methane emerges gradually.
These are pretty much the only two natural methane "sinks." There are a few small-scale human processes that can make use of methane (for the production of methanol for fuel, for example) and function as artificial sinks, but such efforts would be hard-pressed to capture methane released across nearly a million square kilometers. This, then, is where we start to consider the option of planetary engineering.
Both of the natural processes are, in principle, amenable to human intervention. The oxidation of methane into CO2 and water is a well-understood phenomenon, and relies on the presence of OH (hydroxyl radical); upwards of 90% of lower atmosphere methane is oxidized through this process (PDF). But OH is something of a problem chemical, in that it's also a key oxidation agent for many atmospheric pollutants, such as carbon monoxide and NOx. Although we could produce OH to enhance the natural chemical oxidation process, the side-effects of pumping enough OH into the atmosphere to oxidize all of that methane would be unpredictable, but almost certainly quite bad.
So what about methanotrophic bacteria? Such bacteria have long been recognized in freshwater areas and soil, and have had limited use in bioremediation efforts. Methanotrophic Archaea -- similar to bacteria, but a wholly different kingdom of organism -- were recently identified in the oceans; research suggests that methanotrophic Archaea may be responsible for the oxidation of up to 80% of the methane in the oceans. Methanotrophic microbes can also be temperature extremophiles, as they were among the various species found after the Larsen B ice shelf collapsed.
We recently began to learn much more about how methanotrophic bacteria function, as a team from the Institute for Genomic Research sequenced the genome of the methanotroph Methylococcus capsulatus. The scientists discovered that Methylococcus has the genomic capacity to adapt to a far wider set of environments than it is currently found in. They also looked at the possibility of enhancing the microbe's ability to oxidize methane, although admittedly for purposes other than straight methane consumption.
You can see where I'm going with this.
Freshwater methanotrophs are increasingly well-understood, but present a limited means of methane remediation. Methanotrophic Archaea have demonstrated ability to act as a major methane sink, at least in the oceans, and to live in extreme temperature conditions. Neither is a good fit for Siberia. The Siberian arctic, while warming, remains damn cold, but the melted permafrost lakes will be freshwater settings.
It appears to me that what will be the most effective means of mitigating and remediating the gargantuan methane excursion from the Siberian permafrost melt would be using genetically-modified forms of methanotrophic bacteria, with greater oxidation capacity and the Archaea-derived resistance to extreme cold (these may well go hand-in-hand, as one way that deep sea methanotrophs survive the icy depths is through internal energy production from methane consumption). Given the size of the region, we'll need lots of them, but that's another advantage of biology over straight chemistry: the methanotrophs would be reproducing themselves.
It's unlikely that abundant reproduction of GMO methanotrophs would pose a larger risk -- at the very least, they'd be limited to the post-permafrost lakes, as they'd be based on freshwater-only species -- and a mass of methanotrophic organisms would undoubtedly be helpful for reducing overall atmospheric methane beyond the Siberian release. More importantly, the successful introduction of such organisms would give us practice for what would be a far, far greater problem: the undersea methane clathrates, which are believed to contain upwards of 500 billion tons of CH4. Undersea clathrate melts have been implicated in mass extinctions in the geologic past; the significant climate warming that would result from an unmitigated Siberian release would pale in comparison to the effects of a clathrate melt.
What are the outstanding questions we need to answer before we could consider creating GMO methanotrophs?
If you think I'm suggesting this option in a casual or flippant manner, you need to read Terraforming Earth essays one, two and three. Planetary engineering -- including the widespread release of genetically modified organisms to combat atmospheric changes -- should only be considered when more readily reversed and managed solutions are no longer available or functional. In the case of the Siberian methane, the more cautious options are extremely limited. We're no longer in a position to stop the melting, even by ceasing all greenhouse gas production today; the temperature increases we're seeing now are the results of greenhouse gases put into the atmosphere decades ago.
In a way, among the different scenarios forcing us to consider "terraforming," this is probably close to the best choice. Failure would be drastic, but not utterly catastrophic (unless the resulting warming, in turn, melts the undersea clathrates, at which point all bets are off). The engineering options are enhancements of natural processes, as opposed to something beyond current experience (such as putting a "solar shade" between the Earth and the Sun to reduce overall insolation). At least with current understanding, a "runaway" condition for the terraforming effort would not mean widespread extinctions (such as would the "runaway" scenario for boosting phytoplankton blooms in the oceans). And, as noted, this would allow for better refinement of technique and understanding of choices in the face of a similar-but-greater in magnitude problem down the road (in this case, the aforementioned clathrates).
A further advantage is that this is a process that could begin after we start to see significant methane output and could still have a measurably positive result. Using microbes for bio-"scrubbing" of methane from the atmosphere would work on methane that was a decade old as readily as methane fresh from the bog. We'd still see some effect from the methane that makes it to the atmosphere, but eventual removal would help to reduce that effect. This means that, should we face a situation where questions still need to be answered before we could comfortably begin to use the GMO methanotroph option, but we're starting to see an impact from the Siberian release, we don't necessarily have to rush past our better judgment in response. With a process of this magnitude, it's worth taking the time to get it right.
I imagine that this, as with the previous Terraforming Earth essays, will trigger some heated questions and discussion -- or, at least, some deep reflection on human choices. I must emphasize again that I don't consider large-scale projects like this to be favored options; I have a strong preference for reversibility, flexibility and limited second- and third-order effects. Planetary engineering -- Terraforming -- embraces none of those three standards.
But if these reports are true (and it remains a very big if, for now), we would be facing a problem of a scale with few precedents in human history. No society on the planet would be unaffected; if left unmitigated, it would continue to affect the lives of our children, and our children's children, and generations beyond that. And -- again, if the reports prove accurate -- this is not a process that can be readily stopped or prevented from happening.
Our choices are few, and the risk of not acting is (potentially) immense. We may well be on the brink of a new era in planetary management. Let's hope we're up to the challenge.
(Thanks to Jason Cole, wintermane, David Foley, Stewart Brand, the myriad others who forwarded this link.)
Jamais, great follow through on the Siberia article.
Your proposals make a solar shade look like a much better option. Jim Lovelock suggested that very thing to me 15 or 20 years ago when he realized what his Gaia Hypothesis was implying about potential heat-runaway mechanisms on Earth.
Thanks, Stewart. I have a few reasons for hesitation regarding the solar shade.
First is the cost; the expense of building the launch capacity to put something of that size in a Lagrange point orbit, the cost of the necessary materials, and the requirements for simply figuring out how to build it in the first place would run well into the hundreds of billions of dollars. This is obviously an achievable expense -- viz. the Iraq war -- but also one that would far outweigh the expense of figuring out the proper safe modification of methanotrophs.
Second is the potential for unanticipated effects; we don't know what sort of impact a permanent reduction of insolation would have on plant and animal life evolved under a sun that only changed output levels very slowly. Moreover, it's not something that would be easily tested, as isolated plant and animal tests wouldn't capture combinatorial effects across ecosystems. Methanotrophs are more readily tested in smaller settings.
Third is reversibility; there would be both physical/logistical and institutional resistance to removal of the shade, even if it was shown to have deleterious side-effects. Something that big and expensive is not going to be easily removed, at least not with current and near-future space technologies.
Reversal of widespread use of methanotrophic bacteria would also be difficult, but has the advantage of partial reversal being a possibility. Reproductive rates could be slowed, local populations cleaned out, etc., which may be enough to mitigate the unexpected results arising from the methanotroph use.
Another drawback to a solar shade:
Industry may insist that it be privately funded, and for several thousand years we'll have to put up not only with a black dot on the sun's disk, but a black dot with a Nike Swoosh cut into it.
Can anyone guess at the size of the financial investment required to acheive something like this? Aside from deployment and future (possible) cleanup operations, what would it take to complete the first stage of laboratory work developing these organisms?
I'm imagining that a team of ten or so scientists, a 2-3 million dollar laboratory, two years of work - we're still way, way, under a hundred million.
That's the tiniest fraction compared to the Exxon Valdez cleanup or other similar disasters. It seems like this might be worth researching even if it's not eventually deployed.
I'm really enjoying these essays. you should consider writing a book based off the premise.
and the solar mirror would be easy to remove. if it's at a lagrange point it's like a ball sitting at the top of a ill. give it a small push to the sun and gravity would do the rest.
Thanks, Andrew. You're right -- getting rid of it wouldn't be that difficult. But that would be a pretty extraordinary waste of the materials used to build it.
I should correct something I said in my reply to Stewart. I claimed that the reduction in insolation would be unprecedented. It's not; the "global dimming" effect from atmospheric particulate pollution provides a fairly similar reduction in insolation. Given that the cleanup of pollution is leading to a reduction in "dimming" -- and hence a speed-up of warming -- we may need the solar shade for entirely different reasons.
Excellent essay, Jamais. Dead on.
One additional application of the GM methanotropes: rice.
We could always crome plate nevada...
There are plenty of materials reasonably ready to hand for making things like sunshades; we call them "asteroids".
One of the skeleton posts in my queue (that I may never finish) is an analysis of what it would take to move certain known rocks to the required position and re-shape enough of it into a shade to do the job.
For the "solar shade": it would seem that mylar balloons -- dirigible sized -- would be a lot easier to put into orbit than asteroids.
It would seem that asteroids are already in orbit, which saves quite a bit of effort.
As for methanophages, culturing strains which prove good at consuming emissions from bogs etc. and spraying them across wide swaths of land might ameliorate this problem. For that matter, so might schemes to harvest the methane for fuel before it leaks into the atmosphere ("use it or lose it").
Collection stations. Then processing plants to liquify the gas.
I may be mistaken, but isn't the moon, Luna, at one of these Langrange points?
A long distance, unless.
A few years ago, a viable working model of an ion propulsion engine wsa discarded by NASA. The fuel was to be mercury.
An ion rocket motor would permit a constant 1/10 gee space travel. Round trip to the moon, 49 days or so. Round trip to the suitable Langrange point for the space shade, less time then to go to the moon and back, using old style single thrust, then drift model.
Fuel constant 1/10 gee space travel by a ion engine fueled by liquid methane anyone?
Sumitted with respects,
Such wonderful news to wake up to. I like to go over to google news and type in things like "methane" and see if there are any American citations attached to such a story. Granted, this has not been peer reviewed, but even Congress knew something was amiss in the Arctic last year. Is there a conspiracy to keep such reports out of America's news? Is it some sort of mass hypnosis affecting news rooms? Or are we just so asleep at the wheel? The top search at technorati today is about Cindy Sheehan. The top Times emailed article is, remarkably, David Brooks meanderings about cultural geography and relativism. I don't see any bogs pictured at tenbyten. My mother used to say "If it is so important we would have heard something about it." But she lived in a much different era, when big news was just that, not a factor in corporate calculus or something that had to fit into a prescribed story-telling template.
Asteroids would be fine for the raw materials, in principle, but that would be an untested process, and would add to the expense. When I said simply dumping the shade would be a waste of materials, I probably should have said "resources" -- as in financial resources.
If we were really in the space-faring mood, though, I suppose it could be moved to a similar Lagrange point around Venus and start the terraforming process there.
As for collecting the methane for direct use as fuel or conversion to methanol, that would be helpful, no doubt, but the diffuse nature of the Siberian bog -- remember, we're talking up to a million square kilometers melting at different rates -- would make effective or efficient collection difficult, and would be unlikely to make a big difference to the overall amount released.
Will, I can think of several reasons why this isn't getting much coverage in the US media: (1) it's not coming from a major peer-reviewed journal, so it's easier to dismiss; (2) it's not happening in the US; (3) it's a huge problem that has no obvious solution (NS and the Guardian and the like aren't talking about methane-eating bacteria); (4) it's a "slow-motion" disaster, so there are undoubtedly "let's wait until we see if it's really a problem" type reactions.
"Fuel constant 1/10 gee space travel by a ion engine fueled by liquid methane anyone?"
I'm not sure you have your facts down right.
* An ion motor that can supply enough thrust to generate 1/10 of a g acceleration would be utterly unprecedented. At the very least, it would require an enormous amount of electrical power.
* When you say "fueled" by liquid methane, are you suggesting the methane be used as the "working fluid" (that is, the substance that is ionized and accelerated to produce thrust)? Every ion motor I've read about, real and theoretical, use a heavy metal such as cesium or (as you mention) mercury.
* Or are you suggesting the methane be used as the source of electricity required by the ion drive? You'd need to combine it with an oxidizer, which would have to be shipped to orbit along with the methane. You'd need an awful lot of both, and you may be better off simply using the methane and LOX in a chemical motor.
If 'atmospheric particulate pollution provides a fairly similar reduction in insolation' that slows global warming, why not just pump suitable dust into the upper atmosphere. Perhaps that would be cheaper than a solar shade at a Lagrange point?
In response to joseph zack's comments.
Anytime you have two bodies with significant gravitational attraction, you have multiple LaGrange points relative to them. Luna is not sitting in a LaGrange point; it's in a regular orbit around the Earth. However, the Earth and Luna have multiple LaGrange points, as a result of their gravitational interactions. One of those LaGrange points is between the Earth and Luna. Consequently, if you can get to that point (I believe they call it L5), you can establish an orbit around the Earth, synchronized with Luna's orbit. Normally, at that range from the earth, you'd have to be moving a lot faster (and, consequently, orbiting the earth much more often), but Luna's gravity balances with Earth's gravity to make it all possible.
An idea which Jamais might want to consider: you can orbit a LaGrange point, so long as those "orbits" are kept real small. Consequently, instead of making a massive sun shade and putting it at a LaGrange between the Earth and Sol, pull a bunch of asteroids into a small, circular orbit around that LaGrange point. As the number asteroids in this area increases, they will block progressively more energy coming from Sol. Need to reduce the amount of shade? Kick a few of the asteroids OUT of their orbits. Need more shade? Guide a few more in. We're only wanting to block a few percentage points, right? Then we don't really need a large, solid object sitting out there.
O.k. My bad. Just a couple corrections on my statements.
There are five LaGrange points anytime you have one body orbiting another (such as Luna orbiting the Earth). The one in between is called L1.
There is an online simulation available (note: you need a Java-enabled browser to play with it). Set the "Instance" to "L1-L5 M/m=40", set "Integrator" to "Animate Only," set "FrameRotationRate" = 0.01 and "dt" = 1, then hit the "Start" button. The result is a pretty good visualization of the LaGrange points relative to the earth and the sun. I can only imagine what a simulation would look like which covered Sol and all planets out to, say, Jupiter (beyond that, the distances are so great and the gravitational attractions so small that the points would have little use).
Joseph Zack wrote:
"Collection stations. Then processing plants to liquify the gas."
Well, this would require more energy to collect and liquify than it could possibly yield. Similarly, hydrogen is the most abundant element in the universe, and it can be burned as fuel. Yet you can't just run out and "collect" hydrogen.
If we can have serious discussions of genetically-modified methanophage bacteria, solar reflectors at Lagrange points, launching enough power into space to tow asteroids around, could we please have a serious discussion of factor-10 efficiency improvements, carbon taxes, rapid and widespread deployment of renewable-energy technologies, serious worldwide family planning, natural habitat restoration, and other steps that we desperately needed to take 20 years ago?
I'm sure most readers know the First Rule of Holes. In case you don't, it's this: when stuck in one, stop digging.
David, as I'm sure you know by now, I am in total agreement that we need to stop making things worse immediately. The point of my post was simply to look at what it might take to handle a potentially very serious situation that, if it is in fact happening, is beyond our ability to stop from happening, no matter how efficient we get.
Think of it this way: if the methane dump from permafrost melt does happen, then the resulting economic and environmental dislocation will be sufficiently serious as to hamper any other efforts to improve efficiency, etc.
I understand Jamais, and my apologies if I seemed to overlook key points in your excellent post. The ensuing discussion seemed, to me, to focus on difficult, expensive and untried palliatives. Sadly, we're going to need to consider such schemes, but the proven, affordable, available and simple acts seemed to be overlooked. The converse of your last point is true too: unless we take immediate bold steps toward efficiency, renewables, family planning and habitat restoration, we won't stand a chance with whatever "terraforming" schemes turn out to be practical - and if we take those steps, we just might not melt the permafrost. It's one of my peculiarities that I find avoiding problems more elegant than solving them.
Joseph Zack has shown
His premium membership
in "The Great Confused".
Regarding methane, IIRC there have been some tests of the liberation of methane from permafrost hydrates in Canada. If this methane can be tapped (and converted to liquids?) before it gets to the atmosphere, Siberia could have a huge energy boom and the net greenhouse influence could be cut drastically.
If they decide the methane is worth the money they are most likely to strip mine all the peat and hydrates and fling it into titanic digesters prolly along with any pesky forests that might be around the area...
Great concepts! Thanks to all. Perhaps a combination: My understanding of a sun shield is that (without using reversed binoculars) it would have to be as big as the earth for full blockage, and some percentage of that size for partial blockage. We could build a relatively small one out of aluminized mylar, and avoid the launch cost by using it to cover the affected area of Siberia. Not only would it reflect energy, it would simplify collection of the methane which could then be used to power "nuclear winter" dust generators (I'm sorry, that should be "nucular"). The bacteria could remain busy under the mylar blanket.
No need to do a bioengineering effort using archaea and as one engaged in such research I think you greatly underestimate the complexity, difficulty and years (many) required. In any case the methanotroph genome sequencing link for TIGR goes to the press release for the paper "Genomic Insights into Methanotrophy: The Complete Genome Sequence of Methylococcus capsulatus (Bath)" by Ward et. al. PLoS Biol. 2004 Oct;2(10):e303. Epub 2004 Sep 21. After reading it I think where you miss a bet is when you state that freshwater methanotrophs "present a limited means of methane remediation." If anything the paper's information about the environmental versatility of M. capsulatus suggests the reverse is true. A far easier solution than a complex genetic engineering project would be to find, grow and spray naturally occurring methylotrophs. However, a potential problem with the entire approach is whether the methane built up over the past 11 thousand years will simply be released too fast for bacteria (or archaea), engineered or not, to have a chance to eat it.
The overall problem I have with terraforming is that is a pretty massive undertaking, especially if across the globe societies are experiencing massive societal and economic problems from global warming. I just don't see the likelihood of resources being available in time. Far better to work hard to avoid and mitigate the problem than to advocate for "pie-dish in the sky" solutions that require deployment of a new generation of spacecraft. I think it far more likely we could build (in time to matter) Buckminster Fuller's global solar collection grid using a superconducting transmission system to provide 30 terawatts of solar power distributed globally, so as to replace CO2 releasing power generation. This is a solution that would pay for itself as it goes - not a minor consideration.
Not that I oppose space exploration and space industry. In fact I think that is where all our polluting industry should and will go. I also think we probably will come back to terraforming Earth to maintain climate on Earth within certain bounds. I just think we need to find answers quickly (before ocean warming melts clathrates for example or some other catastrophic feedback bites us in the butt.) Solar cells are off the shelf technology, are already a feasible solution and covering enough area to matter simply means building more factories with slight technological improvements.
The University of Wales researchers who looked at the Siberian bogs have a history of prior bog research, particularly in North Wales. In their prior research, they identified and sought to explain the causal mechanisms behind the accelerated release of dissolved organic carbon in surface waters in and around bogs. It seems that as carbon concentrations in the environment (particularly in the atmosphere) increase, this accelerates the release of carbon from bogs.
If the global atmosphere changes as a result of releases from the Siberian bogs, then if I understand the U.W. researchers correctly, this could alter the rates of carbon releases from bogs around the globe.
The scope of the problem raises questions of climate change mitigation. For example, we could look at impacts on near-shore ocean water quality from chemical and petroleum releases (or just fecal coliform from failed sewage systems) that would happen if sea levels rose faster than closure activities of chemical storage facilities. Some potential sources of releases could not be relocated, landfills for example, and they would subsequently degrade surface water quality in fragile coastal areas.