Geoengineering: A (Very) Risky Proposition Says Study
by Jeremy Elton Jacquot, Los Angeles on 06. 5.07
Perhaps it is not surprising that a plan that seems to draw its inspiration in part from The Simpsons’ Montgomery Burns’ ill-fated scheme to block out sunlight through the use of a gigantic shield would prove controversial, let alone extremely risky. Now a recent study has determined that while such a scheme may help to dramatically cool the planet, it could just as easily worsen current conditions.
Ken Caldeira, of Stanford's Carnegie Institution, and H.Damon Matthews, of Concordia University in Montreal, Canada, specifically examined what might happen if a solar filter was put into place by using a computer model that simulated a global decrease in solar radiation. The authors assumed in their model that greenhouse gas emissions would continue their steady increase along projected trends for the remainder of the century.
“Given current political and economic trends, it is easy to become pessimistic about the prospect that needed cuts in carbon dioxide emissions will come soon enough or be deep enough to avoid irreversibly damaging our climate,” said Caldeira. “If we want to consider more dramatic options, such as deliberately altering the Earth’s climate, it’s important to understand how these strategies might play out.”
While the model predicted that the geoengineering system could drastically cool off the planet within a few decades even in the face of rapidly increasing emissions, it also seemed to suggest that were the program to fail or be cancelled for any reason, a huge decade-long rise in global temperatures at rates far outpacing the current ones (up to 20 times greater) could occur. Another worrisome consequence of deploying this system would be a large decrease in global rainfall patterns.
“If we become addicted to a planetary sunshade, we could experience a painful withdrawal if our fix was suddenly cut off,” Caldeira said. “This needs to be taken into consideration if we ever think seriously about implementing a geoengineering strategy ... Many people argue that we need to prevent climate change. Others argue that we need to keep emitting greenhouse gases. Geoengineering schemes have been proposed as a cheap fix that could let us have our cake and eat it, too. But geoengineering schemes are not well understood. Our study shows that planet-sized geoengineering means planet-sized risks.”
Although Caldeira and Matthews aren't enthusiastic about the prospects for geoengineering, they don't think it should be taken off the table altogether. As Caldeira wrily noted: “I hope I never need a parachute, but if my plane is going down in flames, I sure hope I have a parachute handy. I hope we’ll never need geoengineering schemes, but if a climate catastrophe occurs, I sure hope we will have thought through our options carefully.”
Via ::Geoengineering -- A quick fix with big risks, ::Simulation shows geoengineering is very risky
See also: ::The Economist Discovers Geo-engineering, ::Wild and Crazy Ideas to Cool the Planet, ::Crazy Solar Shield Not 100% Crazy
Sigh...once again man thinks it's better to overpower nature rather than work with her.
Don't we use sunlight to grow our food? Won't dimming the sunlight dim our food production?
The planet needs to reestablish an equilibrium between the release and the capture of carbon dioxide. Personally, I believe that nature's equilibrium, which has evolved to its current state over many many millenia, is the one we should be striving for. Society needs to drastically reduce emissions, and society needs to restore as much as possible natural ecosystems so that they can resume their carbon dioxide capture and sequestration. Geoengineering a man-made equilibrium is extremely risky and would be a poor second-best option. However, as said in the article, we can not take geoengineering off the table. I believe we need to do all possible to restore the planet's natural balance, and then, if after decreasing emissions as much as possible and restoring ecosystems as much as possible, the balance is still off...then we should consider applying small-scale geoengineering to finish the rebalancing. The smaller the geo-engineering projects, the less risky because if they do go wrong, their negative impact will be smaller. That means society's focus must remain in emissions reductions and ecosystem renewal - and geoengineering should remain as a backup option to fill any (hopefully) small balancing gap.
We could try carbon dioxide sequestration using charred biomass, which seems promising.
Worst case scenario, Dyson sphere!