Geoengineering: Can we fix the climate without reducing emissions?
Can we fix the climate without reducing emissions? Might there even be a way to fix the climate that is cheaper then reducing emissions and doesn't have side-effects? In this post I will look at some of the more creative proposals for fixing the climate, and see if they are any good.
Many of the ideas I'll present here sound like crazy-talk at first, and I'm not saying that they necceceraly aren't, but I don't think they should be disregarded before we have considered them.
I'll start with one of the most popular ideas: Pumping fine particles of sea-water into clouds to make them bigger and more reflective.
This youtube-video explains it all:
The good thing about cloud-seeding is that it can be very cheap. As mentioned in the clip only 500 litres of salt water a second, or something of that magnitude, needs to be sprayed up in order too control temperatures on earth. We would need roughly 1500 ships to counter-act a doubling of CO2 in the atmosphere, costing 1,5 to 3,5 million dollars each. And to keep up with the current rate of increase in atmospheric carbon-dioxide levels we would need 50 new ships a year. Not that much for saving the climate. The Copenhagen Consensus Center, where top economists have tried to estimate the costs and benefits of different solutions to climate change, write this about the costs:
Marine cloud whitening with a fleet of unmanned ships would be extremely cheap: for about $5.8 billion, all of the global warming for the century could be avoided.
But is it possible that seeding the clouds might change the worlds weather patterns, and lead to droughts, etc? Yes. That's one of the reasons why we need to research this a lot more. But one of the great things about marine cloud whitening is that it's so flexible. If placing the boats one place leads to problems we might solve the problem by simply moving the boats. Maybe we even can make the worlds rain-patterns better (by prevent droughts, etc.) if we gain a good enough understanding of the climate system and how cloud seeding affects it? Since the boats can be controlled the amount of cooling can also be controlled, via satellite measurements and a computer model.
And what do we do if marine cloud whitening doesn't work out? Then we stop doing it, and everything will return to normal within a few weeks. Which also means that it will be risk-free to do small-scale testing of the technology.
But hey, you might think, won't the clouds become salty? Well, in a way they already are, as tiny salty water droplets from breaking waves already enter the atmosphere and help forming clouds. Marine cloud whitening only enhances a natural process. As far as I understand, the water always needs something to cling to (particles like dust, smoke, or salt) in order to form clouds, but when the clouds first have started forming they grow really big, and become mainly freshwater. So there is no danger of there raining salty water if we start with marine cloud whitening.
Releasing sulfur in the stratosphere
Picture of the volcano eruption at the Philippines in 1991, which reduced world temperatures by 0,6 degrees.
In 1991 Mount Pinatubothere, a volcano in the Philippines, had a huge eruption. 10 million tonnes of sulfur was ejected into the stratosphere - the part of the atmosphere which is placed at about 10-50 km (6 - 31 miles) above Earth's surface. The sulfur was moved in different directions by the air motions, and after about a year it was evenly spread around the world. For two years after Pinatubo erupted, the average temperature on Earth decreased by about 0.6 Â°C (0.9 Â°F).
The idea is to send up rockets (or baloons, or some other mechanism) to simulate a volcano eruption. At first normal fuel is used to lift up the rockets, but in the stratosphere hydrogen sulfide is burnt, leaving sulfate (which consists of sulfur and oxygen) in the stratosphere to reflect sunlight, and thus cool the planet. Of course this wouldn't be free, but a lot cheaper than cutting emissions. Paul Crutzen, one of the top experts on this subject, has estimated that it would cost between 25 and 50 billion dollars a year (in comparison we spend over a thousand billion dollars a year on the worlds military and well over 250 billion dollars a year on subsidizing farmers in developed countries). And we have all the necessary technology to implement this measure at once, if we want to.
But unfortunately this is not a problem-free solution. We don't yet know if it would disturb rain-patterns. And emitting sulfur is considered as polution, because it leads to health problems and because it leads to acid rain. That's why the release of it has been reduced through environmental regulation. It is naturally emitted by volcanoes and by the sea, but we shouldn't get to much of it.
However, it should be noted that this sulfur would be released far up in the stratosphere. And further: Since it will have a greater cooling effect when released in the stratosphere it is predicted that we will need too release less then 10 percent of what is already being emitted by humans. A side-effect that there is a bigger reason to be afraid of is that releasing sulfur in the stratosphere might slow down, or even reverse, the healing of the ozone layer. The volcano eruption in 1991 led to a global column ozone loss of about 2.5 percent. However, we won't need to use as much sulfur as was emitted in the colcano eruption in order too compensate for a doubling of CO2 in the atmosphere through geoengineering.
The ozone layer is healing. It's better than it was a few decades ago, and it will continue to get better. So if we start reducing temperatures some decades from now the ozone layer won't necessarily get worse than it is now, only worse than it otherwise would have been then.
Ironically one the people who has done the most research on releasing sulfur in the atmosphere is Paul Jozef Crutzen, who won a nobel prize in 1995 for his work on the hole in the ozone layer. He thinks that we at least should test his plan, so we know now what the risks might be if we face a catastrophic situation in the future. He says:
Since the sulfur only stays in the stratoshpere for two years or so, he also makes clear:
I am prepared to lose some bit of ozone if we can prevent major increases of temperature in the future, say beyond two degrees or three degrees.
It is being discussed if we could use other cooling particles than sulfate. If you are interested you can see a short presentation that mentions this here.
Such a modification could also be stopped on short notice, if undesirable and unforeseen side-effects become apparent, which would allow the atmosphere to return to its prior state within a few years.
Launching glass discs into space
This is what the glass discs might look like. They won't reflect the light, but divert it from hitting earth.
Another idea is to launch glass discs into space so that roughly two percent less sunlight reaches earth. The reduction in incoming sunlight would cancel out the increase in climate gases. The plan isn't as crazy as it sounds. Even without using nanotechnology (which is emerging) we can get these glass discs pretty thin, and there are realistic ideas for how we can launch these glass discs into space by using electromagnetic power (much more effective for sending large quanteties out in space than using space ships). By placing these glass discs at the point in space where the gravitational force of Earth and the Sun cancel each other out (which is pretty close to earth) we won't need much energy to keep them in place. But even though the idea is feasible and has small side-effects it will be very expensive (although probably not as expensive as drastic cuts in emissions) and will take 30 years or so to implement. Therefore I won't use more space on it here, but if you are interested in learning more about it you can see this youtube-clip, and continue on to see this. And if you are especially interested you can read more about the arguments for and against here.
Getting the sea to take up more CO2
The phytoplankton turns sunlight into energy, and thus provides food for the rest of the food chain as well, just like plants on land do. Had it not been for phytoplankton the sea would have been a lot less lively than it is today.
Three fourths of the world is covered by the ocean, which naturally absorbs about one third of our CO2-emissions. In the sea it's not just "normal" plants that get their energy from the sun, but also phytoplankton. Phytoplankton account for around half of all photosynthetic activity on Earth.
The phytoplankton absorbs CO2, and releases oxygen. It doesn't release the carbon when it dies. Much of the plankton is eaten by other sea-creatures, but much of it also sinks further down in the ocean and stays there for a long time. Planktos-science.com tells us:
Phytoplankton rely on minerals. In parts of the ocean the growth of phytoplankton is limited by lack of iron, and across most of the sea we can boost the phytoplankton-growth by adding nitrogen. The idea is to add nutrients to the ocean, and thus boost the growth of phytoplankton, so that they turn more CO2 into oxygen and make sure that more carbon is stored in the ocean. This youtube-video explains the idea in greater detail:
In a managed bloom, carbon sequestration occurs when dead plankton and other organic waste material sink to the deep ocean as â€œmarine snow". The duration for which the carbon is sequestered is measured by the depth it reaches. Carbon that sinks below 200 m will be sequestered for decades, carbon that sinks below 500 m will be sequestered for centuries, and carbon that sinks below 1000 m will be sequestered for millennia.
Phytoplankton takes energy directly from the sun. And just like all animals on land are dependent on plants to provide energy, phytoplankton (and other sea-plants) are the foundation for life under the sea. As seen in the clip there is such a thing as too much phytoplanton, but it's important that we seperate between the deep sea and the parts of the ocean that's close to the shore, and between iron- and nitrogen fertilization. Acording to planktos-science.com phytoplankton blooms on the high seas where iron is limited have never been reported to produce negative environmental effects. And as explained in the clip, it's like irrigating the dessert. If it doesn't work out, we can stop doing what we are doing, and things will return to normal.
The picture shows a phytoplankton bloom off the coast of Norway in 2000. Image provided by the SeaWiFS Project, NASA/Goddard Space Flight Center and ORBIMAGE.
Plankton-blooms occur naturally all the time. And the ocean is supposed to be "fertilized" with minerals. This happens naturally when dust is carried by the wind and lands in the ocean. Much of the life in the ocean is totally dependent on this.
But the natural flow of dust containing minerals vital for phytoplanton has been reduced significantly over the last decades. According to NASA, the amount of iron deposited from desert dust clouds into the ocean has decreased by 25 percent since the early 80's. In addition to this the growth of phytoplankton is reduced when sea temperatures rise. An article from NASA 2003 tells us that there has been a 6 percent reduction of phytoplankton growth in the ocean as a whole over the last two decades. Newer studies confirm this picture of phytoplankton growth decreasing. Near the shore phytoplankton growth seems to be increasing, but this is not relevant to the queston of iron-fertilization, which will take place in the deep ocean where the growth of phytoplankton is limited by the lack of iron.
The fact that the growth of phytoplankton, and even the natural supply of iron, has been reduced significantly because of human activity, means that we don't have to look at iron fertilization as fiddling with nature, but rather as making it more simular to what it would have been if we hadn't interfered at all.
In an interview with treehugger.com, which I recommend reading in its entirety, David Kubiak from Planktos, Inc. claims:
Returning plankton populations to 1980 levels would neutralize about 50% of industrial society's greenhouse gas emissions.
But there is debate about how effective iron fertilization will be. One of the things we don't know for certain is how much of the phytoplankton that will sink to the bottom of the sea or stay in underwater currents for a long time, and how much of it that will be released to the athmosphere more quickly. To read more about the arguments for and against iron fertilization you can click here or here. And to hear the pro-side you can see this presentation by Russ George, or read more on planktos-science.com.
Making artificial "trees"
The idea is to make machines that can absorb CO2 from the air. It can obviously be done. Plants do it all the time. But do we have the technology already? Will it be cost-effective? And will it take a lot of energy? A twelve minutes long video about artificial trees can be seen here for those of you who are interested, but here is a shorter one:
The good thing about this solution is that it doesn't have any side-effects. Let me repeat that. It doesn't have any side-effects. All it does is to reduce the amount of CO2 in the atmosphere. Just as we increase the CO2-levels across the whole world when we emit a lot from one place (a coal power plant heats up the whole world, not just the city it's placed in) we don't have to think about where we place these "trees". The most practical will probably be to place them above the storing-sites for the CO2. 60 million trees, which is roughly the amount needed to absorb all the CO2 we currently emit, will not take up that much space.
Klaus Lackner, the person who is leading the development of these trees, says in an interview with the The Green Inc. blog:
We have reached a point where we can collect CO2 from the air and recover it - at a low cost. Now it's a production issue, rather than an 'inventing new things' kind of issue.
But where do we put all the CO2 when it's collected? One solution is geological storage: Pumping CO2 into rock formations on the bottom of the sea, or deep underground elsewhere, into rock-formations. This is more feasible then it sounds, and has already been done successfully in Norway and Canada. If you are interested in reading more about how and why this works, and about the details, you can read here. The conclusion is that it can be done, and that it can be done safely. Under the high pressure CO2 takes up a lot less space, so we can store quite a lot of it this way, but as far as I know there is still doubt about whether or not we will be able to store all of the CO2 we will emitt in the long run using this method. But already new, promising ideas for how we can store more CO2 are emerging, like binding it to mineral substances. Great! So there we have our perfect solution to climate change.
...Or do we?
Klaus Lackner thinks that the price of using these artificial trees to fight global warming can reduced to roughly $30 per ton of CO2 collected (which corresponds to about 25 cents a gallon or 7 cents per litre of gasoline), in current prizes. In 2006 we emitted 28 billion tons of CO2. Paying for that would cost 850 billion dollars. Of course the calculation would be more complicated than this in reality, partly because it will be cheaper to capture CO2 from point sources where concentrations are higher (such as a coal power plant), but it still won't be cheap.
If we only could fight climate change by reducing emissions we would be in real hurry. And we kind of are also when we take geoengineering into account, since the negative consequences of global warming have started to occur already. But if it mainly is the consequences that will occur in some decades we are worried about (2035? 2050?) being able to take CO2 out of the atmosphere gives us the benefit of being able to wait a bit. This is good for two reasons:
- First of all, as we all know, technology is getting better and better. And there is no reason to think that science will stop advancing soon. Rather to the contrary all the information available to us makes it reasonable to expect that the advancing of technology will keep growing exponentially. I will write more about why I think there is reason to be very optimistic about how much better technology will get in the following decades in later blog posts. In the meanwhile it should be noted that one of the things that will revolutionize our ability to absorb CO2 (in addition to revolutionizing everything else) is the emergence of nanotechnology, which will enable us to design things on an atomic and molecular scale. When we can design things on such a small scale we will not only be able to make very small and very complicated machines, and do much of what we do today much more effectively, but we can also make new materials different from those we have today.
- The advancement of technology increases our productivity, and thus makes us richer. So even if the technology doesn't changes drastically, it will still be easier for us to afford.
Here I have looked at some of the solutions. But there are many other ideas out there. Like creating white, floating islands in places of the sea that we don't use much (of cheap materials, obviously) so that more sunlight is reflected. Or turning the Sahara and the dry parts of Australia into forests. Another idea is genetically engineering crops to be more reflective or shifting to more reflective crops. And although painting our roofs white probably wont solve the problem by itself, it is proposed as a cheap way to make earth colder. There are also ideas for how we can solve specific problems related to global warming, like stopping the melting of Greenland by wrapping the edges with reflective materials - a method that also can be used on glaciers. I agree that many of these ideas sound bad, and some of them probably are, but we should give them a serious look .
Is it crazy to look for a technical solution for global warming?
Some people dismiss geoengineering without even having looked at the different proposals. They'll say things like "you can't fix the climate by fiddling even more with it" or "we can't possibly know the outcomes of geoengineering". Although I think that many geoengineering-ideas aren't advisable, I don't think it's reasonable to conclude that geoengineering in general is doomed to not work or be risky. It might very well be that we soon find a solution that is without risk, without side-effects and cheap. If we don't, I still think geoengineering might be the answer, as long as we find a safe alternative with modest side-effects.
What would happen if we stopped emitting tommorow?
If history is a guide there is little reason to be optimistic about humanity cutting greenhouse-gas emissions. We have broken all climate-treaties so far, and global emission-levels are even higher than the highest scenario produced by the Intergovernmental Panel on Climate Change in 2001. Even stopping the emissions from increasing further would require quite a lot of action, if we are to do it right now. And even if we do manage to take action to reduce emissions it will take time before they are reduced enough to stop the accumulation of climate gasses in the athmosphere.
But let's say that we did take drastic action. Tomorrow all people on earth would stop driving cars, we would stop flying, all energy production involving fossil fuels would be stopped, we would stop all agriculture that emits methane, all industry that isn't environmentally friendly would be stopped, we would end deforestation once and for all, etc. Let's say that we went way further than even the most extreme environmentalists would want us to, and stopped all human emissions of climate gases in just one day. What would happen?
What would happen is that the temperatures would keep increasing. Shortly explained this is because it takes time for the climate system to fully respond to increased emissions. NASA explain on their webpages:
Even if all emissions were to stop today, the Earth's average surface temperature would climb another 0.6 degrees [Celsius] or so over the next several decades before temperatures stopped rising.
Therefore geoengineering-plans might be a more environmentally friendly alternative than just drastic cuts in emissions, even if they have environmental side effects! Don't get me wrong: This doesn't mean that there aren't limits to how much environmental side-effects we should allow, or that a geoengineering-plan that doesn't have environmental side effects at all isn't preferable. And of course I am aware that it's possible to combine geoengineering and big, immediate cuts in emissions, if we think that's smart.
Some geoengineering-solutions, like the ones that rely on decreasing the amount of solar radiation that is absorbed by Earth (glass discs in space, sulfur in the atmosphere, marine cloud whitening, etc.), aren't permanent solutions. We can't keep on emitting CO2 forever. But seriously, who thinks that steering the amount of climate gases in the atmosphere will be a challenge in 2100? We need a solution that solves the problem for long enough, but it doesn't need to solve the problem for ever.
It should be taken into account that a solutions that relies only on controlling solar radiation don't solve other problems connected to CO2-emissions, such as acidification of the ocean.
Let's us say (just for the sake of the argument) that the alternatives are reducing emissions and releasing sulfur in the stratosphere, and (also just for the sake of the argument) that we can stop global warming completely by reducing emissions if we reduce them fast enough. Let's also say (still for the sake of the argument) that we find out that releasing sulfur in the stratosphere will lead to some harm to the ozone, which again will lead to more cases of cancer.
Then we should reduce emissions, shouldn't we? What kind of people would we be if we think it's ok that more people die of cancer?
Well, since releasing sulfur in the stratosphere is a lot cheaper than drastically reducing emissions, we could save a lot of money on choosing this alternative. And if we spent a fraction of the money saved on cancer research we could double the research on cancer many times over, and thus reduce the cancer-burden significantly.
Price matters. We only have a limited amount of resources, so we have to make sure that we achieve the greatest amount of good per dollar.
So how can we most effectively address climate change? Exactly this question The Copenhagen Consensus Center on Climate tried to give an answer to in 2009:
Here is the prioritized list that the top economists (including three Nobel-prize winners) came up with:
As you can see, the highest ranked solutions are research on geoengineering and low-carbon technologies. You can read more about the different solutions on the list, and the reasoning behind how they prioritize, here.
I don't know if The Copenhagen Consensus Center on Climate have gotten their cost-benefit analysis exactly right. An article on Realclimate.org critizises their report on geoengineering. Some of the critisism I think is illegitimate, other parts I think is fair, but I don't think there is any reason to doubt their main conclusions. Regardeless I think their way of thinking is exactly right: How can most effectively fight global warming? If we ranked the solutions after how much benefit (how much they reduce global warming + positive side-effects) we get per cost (what they costs to implement + side-effects), which solutions would make the top? I think this way of thinking to a large degree is missing in the climate-debate. At least it is in my homecountry, Norway.
We should have a plan B!
No matter if you think we should try to solve the climate problem with only carbon cuts or not, you have to agree that we should have a plan B. If it turns out that the world doesn't manage to cooperate on cutting emissions sufficiently even though we should, or if consequences of warming (like methane being released from melted permafrost, or ice melting making Earth absorb more sunlight) leads to even further warming, we should have have developed a plan B to stabilize the climate.
How I think we should solve the problem
I used to be an environmentalist. Of course I wanted us to research a lot on renewable energy and low-carbon technologies, but I didn't think that doing this would be enough by itself. I thought we should drive our cars less, fly less, try to not consume to much of the type of goods that emit the most, choose environmentally friendly energy over fossil energy even when it's considerably more expensive, eat less meat, etc. Not because I wanted it, but because I thought the negative consequences of doing so would be smaller than the negative consequences of not doing it.
I'm still an environmentalist (as mentioned before geoengineering might very well be more environmentally friendly than just drastic cuts in emissions) but I now propose a different way of handling the problem:
Funding research on renewable energy is one of the most efficient ways to combat global warming, and will also benefit society in other ways.
- Research a lot on geoengineering and carbon capture.
- Research a lot on renewable energy and other technologies that are important for reducing emisions (environmentally friendly cars, energy storage, etc.). Researching safe nuclear power is money well spent to, but I don't think it's necessary to cover our energy-needs. Funding the development of renewable energy would be a smart thing to do even if it didn't affect the climate. When solar power becomes efficient it will lead to very, very cheap and convenient energy. I think we have good reasons to be very optimistic about renewable energy, and recently wrote a post that you can read here (it's a lot shorther than this one, I promise!) about solar energy, where I argue that solar power soon will be cheaper than conventional energy.
- Research a lot on computers, re-engineering of the brain, nanotechnology and other technologies that is needed to boost our general technological growth. Researching nanotechnology for example, might not be looked at as a way to combat climate change, but might be a very effective way of doing just that because it will enable new technologies that can solve the climate-problem. And that it also gives other enormous payoffs shouldn't be a problem.
- Do emission-cuts, but only the ones that are very cost-effective.
We should at least take a look at it
Even if you don't agree with my conclusions, you should agree that we should give research on geoengineering more funding. From a global perspective it would cost almost nothing to give geoengineering a closer look, and boost the research on some of the more promising geoengineering-ideas. So even if you're a sceptic and think it's unlikely that geoegineering will be a good idea, you should agree that we should fund more research on it. The UK Royal Society published a comprehensive and unbiased report on geoengineering. One of their main recomendations was exactly that: We should fund more research on geoengineering.
The Parliamentary Office of Science and Technology wrote in March 2009:
There is currently very little public funding specifically earmarked for geo-engineering. Despite a US Department of Energy White Paper (Unpublished) that in 2001 recommended a $64 million, five year programme, less than $1 million of public money is currently directly funding geoengineeringresearch in the USA. In the UK, the Engineering and Physical Sciences Research Council (EPSRC) has proposed a Â£3 million â€˜Ideas Factoryâ€™ commencing in 2010. To date, therefore, most researchhas been either funded using existing climate science grants or has been unfunded, performed in researchersâ€™ spare time. Researchers in the field believe that an international research programme of around $100 million could advance the scientific and engineering knowledge significantly.
I think it's a nobrainer. We should fund research on geoengineering by at least $100 million dollars - preferably much more. I also think it's important that people learn more about these proposals for dealing with climate change. Geoengineering should be a part of the public debate in the same way as emission-cuts are. I think it's wierd that geoengineering haven't recieved more attention in the media, and it's sad that politicians and enviormentalists know so little about it.
If you didn't like this post, feel free to post a comment telling me why you think geoengineering is a bad idea, or simply how much I suck. If you however did like this post, and like me think it's a tragedy that geoengineering has recieved so little attention: Why not recomend this post to your friends, or help spreading it in some other way?