The former is crucial, scientists say: Society must know the limits and impacts of geoengineering schemes before crisis hits and governments, pinched by a desperate citizenry, cast about for relief. The latter is a political decision.
That decision - fraught with philosophical, moral and practical questions - is increasingly viewed as a key component of any climate plan.
"The reason is the uncertainty," said David Keith, director of the energy and environmental systems group for the University of Calgary's Institute for Sustainable Energy, Environment and Economy. "Even if we cut emissions to zero tomorrow, we would still have climate risk."
"The hard reality is that doing geoengineering might be better for nature than not doing it. It would've been better to not put CO2 into the air, but that's been done now."
Even studying the science has its own peril. Scientists have no way to field test a geoengineering scheme at a scale sufficient to provide reliable data without also exposing vast regions of the globe to the risk of side effects.
To Martin Bunzl a philosopher at Rutgers University, that quandary makes geoengineering right now less an ethical question than a methodological one.
"It's going to be extremely difficult to engage in experimentation that would adequately answer whether the balance of risk and benefits makes it worth it to try geoengineering," said Bunzl, who has studied geoengineering and was part of an ethics panel convened by the Royal Society to explore its moral implications.
Yet we need to try, argue several scientists. The ability to geoengineer is as necessary for reducing climate risk as the need to cut emissions.
Many researchers fear industrial emissions have already pushed the Earth outside the so-called "tolerable window" for climate warming. Average global temperatures have already risen 1 degree Celsius higher than pre-industrial times, with another degree worth of warming likely bought and paid for but not yet delivered, given time-lags in natural cycles. Atmospheric concentrations of carbon dioxide are already 40 percent higher than anything experienced in the past 2.1 million years, the Arctic is warming faster than anyone predicted, and major species declines have been reported by scientists worldwide.
To keep climate within this window humanity has known for much of its existence, scientists say emissions from industrialized countries need to drop 80 percent or more within the next few decades. The United Nations' climate talks in Copenhagen this December are meant to build a framework for that reduction, but climate analysts see scant signs any agreement will emerge soon.
But planetary engineering will likely remain part of society's future irrespective of Copenhagen's outcome. First, Bunzl said, there's a good bet that even with strict enforcement of a plausible international treaty, levels of atmospheric carbon dioxide will end up higher than agreed upon - a so-called "overshoot" that could put the climate outside that tolerable window, with disastrous consequences. Second, he added, "even if there is an agreement, people are extremely naive if they think the world will actually stick to an agreement."
In effect, future generations are stuck with geoengineering because society's main strategy for controlling emissions isn't working well and the climate could prove far more sensitive to emissions than scientists and policy makers think.
"The politics of actually stopping global climate change by mitigating emissions are nasty, brutish and endless," Victor wrote in a recent article in the Oxford Review of Economic Policy. "Geoengineering, by contrast, offers prompt benefits with seemingly small costs."
Those benefits are deceptive. And, Victor stressed, there are many risks.
Today most schemes focus on enhancing the globe's albedo, or reflection, in part because it's technologically feasible, cheap and fairly easy to reverse or undo.
More cloud cover reflects light, so some propose spraying ocean water skyward hoping the aerosols will enhance cloud formation. But that could change rainfall patterns, with attendant risk of drought. Others suggest painting every roof white. But that would offset at most two years' worth of emissions, Bunzl said.
The most favored option today is the injection of sunlight-reflecting sulfur particles high into the atmosphere, if only because, as Victor notes, every few decades volcanoes validate scientists' theories. Also attractive: The option could be deployed quickly and, scientists surmise, would lead to a rapid climate response.
The eruption of Mount Pinatubo in 1991 shot 10 to 20 million tons of sulfur dioxide and other fine particles as much as 40 kilometers high in the atmosphere. A year after the explosion more than half the particles remained aloft in the upper atmosphere, reflecting sunlight and cooling the planet by 0.5 degree C.
Bunzl cites estimates that for $1 billion a fleet of 10 retrofitted 747s could inject sufficient quantities of sulfur in the stratosphere to approximate those effects. Other estimates are higher - closer to $50 billion. Either way, Bunzl said, "it's trivial in terms of time and investment."
There are limits, however. Those particles will fall out after a year or two, requiring constant maintenance. The sky whitens as sulfur concentrations increase, and the atmosphere can only hold so much before ozone depletion and acid rain become problematic.
And the true costs are insidious.
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21 Comments
Add CommentHow is it that such articles totally overlook the technology of sequestering CO2 using biomass pyrolysis. The technique is now proven and only requires more investment to be applied on a worldwide scale! See the technical pages of www.eprida.com for details. Basically, the technique takes any wet or dry biomass, such as swerage sludge and converts it to biofuels and organic fertiliser which remain active in the soil for centuries or even millenia. This is how atmospheric CO2 from fossil fuels are eliminated, and how climate change can be reversed. But to do so, we must build 5,000,000 pyrolysis retorts, a goal that is easily accessable when compared to the number of cars existing in the world...Everything is ready except the will of the Copenhagen negociators...
Reply | Report Abuse | Link to thisWhy is it that we assume climate change to be a bad thing? How much area is currently useless to human beings because of ice? How many arid places would see additional rainfall due to increased water in the atmosphere due to increased evaporation caused by warming? Why is there almost no research into the positive aspects of global warming and climate change and how we can use these changes to benefit us? And finally - doesn't the climate change argument itself assume that the causes are man made? Does this not already represent geoengineering despite it's "accidental" nature?
Reply | Report Abuse | Link to thisWow. Hubris indeed. The idea of scientists (and/or politicians) wanting to control the planet as described is truly frightening. Their misplaced faith in their complicated and incomplete climate models is remarkable; especially considering that our weather/climate system is a chaotic one.
Reply | Report Abuse | Link to thisI would appreciate it if SA would be focus more on the scientific problems associated with the anthropogenic global warming theory.
Reply | Report Abuse | Link to this"Planetary Engineering" will be the biggest, and maybe the last, mistake mankind makes.
Reply | Report Abuse | Link to thisI'm all for science and science fiction, but actually spending money on the former to realize our fantasies of power over Nature expressed in the latter; I beg not. I can't agree more with candide. It will take even more resources and generate more waste to implement such fools' errands than we may or may not be inflicting via our fossil fuel habits now. Ironically, such measures will actually encourage these habits if they are even possible. With no incentive to actually live in sync with our home, we over extend our hubris even further.
Reply | Report Abuse | Link to thisI can't think of a worse use of federal money and/or our political focus.
This whole "greenhouse" spoof reminds me of the Chicken Little parable about the pending disaster of the sky falling...With about as much proof! SA needs to go back to Science and let the politicians find other ways of getting wealthy without them...
Reply | Report Abuse | Link to thisIn Rachael Carson's Book "The Sea Around Us", she explains that we are currently in a 900 year warm cycle that will end in 2300AD. The last cold low occurred in 1400 AD. She cites studies that confirm these 900 year cycles going back to around 3000BC that were supported by sun spot and tree ring data. The last warm high occurred around 500AD. Perhaps we should read and research the available data before we move to declare a world wide panic. I may not be a world famous scientist but I doubt that anything we do here on earth will effect the sun spot cycle patterns. We should be concerned about our planet's health, but a cool head will plan better for the next high point in 2300 than a panicked group of individuals trying to flounder around attempting to set a political direction.
Reply | Report Abuse | Link to thisI wonder why there is no mentiong of atmospheric carbon capture in this article. I'm not referring to on-site CCS, which would have a net effect on reducing the excess carbon from the air. This is 300 billion metric tonnes, or the equivalent of four Mount Rainiers.
Reply | Report Abuse | Link to thisUnless we can find a way to safely remove this burden on the world's climate, we haven't a prayer of keeping global temperature below 2 degrees Celsius by the end of the century.
And 2 C, as we're beginning to learn, may even be too dangerous a level.
'The Thermodynamic Razor states that all earth-alone energy exchanges result in a net eco-degradation. This means no nonsolar tech can be a net problem solver.
Reply | Report Abuse | Link to thisSee my Aug posting at: http://my.ecoearth.info/ where this assertion is proved.
Well, after listening to republicans all day, I'm going to side with them. Support global warming. This species needs to lose a gigantic percentage of its population, at any cost.
Reply | Report Abuse | Link to thisI agree, there's no proof that the greenhouse effect works. I think we should all get our scientific perspective from politicians. F'n stupid species deserves every last bit of death it gets.
We may not have to worry. China (plus US) puts particulate matter into the atmosphere (via coal consumption) at a rate that may couteract global warming!
Reply | Report Abuse | Link to thisFor all of those that embrace warmer climate, I want to remind you that more CO2 means more acid in oceans. Higher temperatures also mean more ice removed from glaciers, which means higher oceans and more people migrating out of their homes because of flooding. Mountaineous glaciers disappearing mean less water for humans, animals and plants to use.
Reply | Report Abuse | Link to thisThe fact is that humans have polluted the skies with too much of CO2 and effects of that are dominantly bad. So the best solution is to limit and sequester that CO2 as soon as possible as much as possible. Any delay just makes it more expensive in the future, due to accumulating worsening of the environment.
My sides hurt now from laughing at this column. Douglas is this a joke or have you lost your mind?
Reply | Report Abuse | Link to thisIf you were to go by the facts http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt you would find that global temperatures have been trending down for over a decade now while Co2 diametrically continues to rise. It doesnt even take a dog catcher to determine that there is no correlation of Co2 to temperature. Unfortunately, miss-information rues the day for the ulterior motives of those who perpetuate this hoax.
If the gullible Drones could think for themselves they would realize that NONE of the gloom and doom predictions of the 1980s and 1990s have come to pass. The man-made global warming theory is falling apart faster than you can say iceberg. Dont be the last one standing.
@Dugetit.
Reply | Report Abuse | Link to thisI do indeed get it. Did you even look to the bottom line of the undifferentiated data on the link you provided, that you use to justify your ... um ... well, I'll be generous and call it an 'opinion'? Almost every trend is UP, UP , UP! So, please, (most of) the audience here is going to be quite immune to such ham-fisted misdirection.
But in any case, I also 'get it' with respect to your disingenuous tactics: you do what so many deniers and sceptics do: selectively cherry pick a small range within a dataset, and use any minor anomaly to trumpet the joys of fiddling while Rome burns.
Think, fellow human: if you are wrong and we go on merrily business as usual, people - possibly millions of us - will die. Possibly your own children and grandchildren will live lives of unimaginable hardship. They will erect a precautionary monument to you with a plaque that reads: my great-grandpa did this to us.
If the climate change believers are wrong, yet we have instigated all the required changes, we will nevertheless have a more just and equitable global community, and a sustainable future as a species of perhaps many more millenia.
Choose your path. Choose YESTERDAY! Choose wisely.
I find myself sitting in the middle of a see-saw. Sometimes I think I want to crawl toward the side of the scientists, who are actually paid to tell us things about our planet (and ourselves). What they tell us is that we are on the brink of extinction. Humanity has never seen the Earth this warm before. And if we do nothing, it will only get worse.
Reply | Report Abuse | Link to thisThen I turn my head and look at the other side. I see all the global warming denyers. Granted, most of them are misinformed by those who have a vested interest in oil, and the status quo. They are so violent in their opposition. They are so numerous. And they are unbelievably stupid. And I find myself wondering why I would want to save them.
But then, when I begin crawling toward that side, I realize it would be suicide. And I don't believe in suicide.
So I will push. I will push for cleaner energy. I will push for cleaner air and water. I will push for better education. And I will push for all like minded people to do the same. We are all in this together.
What if CO2 is not the cause of warming? What if it is gravity variations. See http://www.scribd.com/doc/27343303/Gravity-Causes-Climate-Change. Since there is excess GHGs, CO2 and WV in the air, then why doesn't the GHE use this excesss instead of waiting for man to add more CO2? The IPCC CO2 causes more warming analysis is a fraud. It mis applies the Greenhouse effect by ignoring that all the available photons are already in use and adding more GHGs can not absorb more photons if there are no more photons to absorb.
Reply | Report Abuse | Link to thisIn that case the cost of all this geoengineering is wasted. and reducing the amount of CO2 will probably make it harder for plants to produce food.
Dear JDoddsGW,
Reply | Report Abuse | Link to thisYou really need to read more widely. Might I suggest Google Scholar. Go to any Google search page, look up the top, pull down the 'More' tab and click on Google Scholar. Enter your search terms: might I suggest "global warming". Read. Learn. Come back here in six months.
mankind can do better by co existing with nature than confronting : Mankind is a sub set within the set (nature) and needs to realize this.
Reply | Report Abuse | Link to thisScary, scary stuff...
Reply | Report Abuse | Link to thisCould I perhaps persuade you to go the other way? Sequester carbon, treat water - you know: the clean way?
No?
Oh, well.
Then let's keep injecting crap into the air and water. No. No no no, you're right! Let's find MORE and BETTER crap to inject by the shiploads into the air and water. I can't think of a better way to finally kill off ALL politicians. Everything else has failed so far, so go for it!
There can be quite a lot facts undetermined about climate change,all the effort done is just quenching the fire of a cartload of firewood with a cup of water. As for cliamte change, it's a natural process during the development of earth, maybe human beings ourselves were a result of it. No use resisting.
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