There was an interesting article in the Times today about the possibility of “geoengineering”:
In the past few decades, a handful of scientists have come up with big, futuristic ways to fight global warming: Build sunshades in orbit to cool the planet. Tinker with clouds to make them reflect more sunlight back into space. Trick oceans into soaking up more heat-trapping greenhouse gases.
Their proposals were relegated to the fringes of climate science. Few journals would publish them. Few government agencies would pay for feasibility studies. Environmentalists and mainstream scientists said the focus should be on reducing greenhouse gases and preventing global warming in the first place.
But now, in a major reversal, some of the world’s most prominent scientists say the proposals deserve a serious look because of growing concerns about global warming.
I don’t really have a lot to say on the subject– global warming isn’t my thing– but I thought it was a reasonably good read. And the question it raises is an interesting one: should we start to think about pie-in-the-sky ways to slow or reverse the problem of global warming, or should we maintain an exclusive focus on reducing emissions in order to prevent future warming?
My immediate impression is that emissions reduction is cheaper by several orders of magnitude, but there’s something extremely cool about the idea of orbiting space mirrors to cool the planet…
All I know is that if you change forests into grasslands, you’ll get more food, but less industrial production.
Our technology and population has reached the point where we will be modifying the climate, we may as well admit it and discuss the means and ends. (and yes, decreasing greenhouse emissions is preferred)
I am not an expert, but my feeling is that this is the most feasible, and probably has the least side effects:
Another idea was to fertilize the sea with iron, creating vast blooms of plants that would gulp down tons of carbon dioxide and, as the plants died, drag the carbon into the abyss.
The ideas with mirror or lenses seem to be to difficult. Fascinating, yes. Maybe we use in hundred years to cool down Venus…
I guess running the planet’s climate can’t be that much harder than running the world’s economy.
I think this is a wonderful idea. The government should go away, figure out which of these is the most feasible, and calculate the cost. It should then present it to the public who, once they’ve stopped vomiting in horror, will be somewhat more receptive to emission restrictions.
Sadly some people only really think in terms of money.
This sort of thing certainly appeals to my inner geek, but such schemes are easy to announce and hard to implement – and only mitigate the problem rather that solving it.
Besides, we’ve all seen the future, or at least one of your co-bloggers has:
http://scienceblogs.com/grrlscientist/2006/05/global_warming_or_none_like_it.php
Difficult as they are, the technical problems are the easy part. More difficult is trying to determne the ecological consequences of any such scheme. The really difficult problem, however, is political. Any deliberate climate change is going to have both winners and losers. Who decide? Lacking a world government, will we extend domination of the rich countries so that they get to adjust the global climate to suit their needs? For example, what if some action would benefit the climate in North America and EU while at the same time disrupting the monsoon in Asia?
While I certainly think it would be AWESOME, I really don’t think that giant orbiting pies would be the most efficient means of cooling the Earth.
YPMV.
While I certainly think it would be AWESOME, I really don’t think that giant orbiting pies would be the most efficient means of cooling the Earth.
But think of the pie-blogging…
A satellite picture at Earth Observatory got me interested in this a few years ago, and I read that the “iron hypothesis” algal bloom method might have a few drawbacks: (1) substantial increases in deep sea pH, so maybe die-offs of… whatever’s down there. OK, maybe a price “we” can pay. But also (2) possibility of methane production, which is worse than CO2 for global warming. But I suppose only some of the CO2 would be converted to CH4, so maybe there would still be a net benefit for us non-deep-sea-dwellers. “More study is needed,” but I suppose it’s an emergency plan.