I just finished reading Superfreakonomics. Bad title, and really not as good as the first book (essentially because it spends more time dealing with fewer, less novel ideas), but the final chapter (Why is Al Gore like Mount Pinotubo?) — which discusses Climate Change — basically underlines the fact that we know how to solve Climate Change and the question simply is how long before we feel compelled to employ a (real) solution?
The solution put forward in the book (which is the same as that described in the Atlantic article, linked above) is to increase the Earth’s albedo by injecting sulfur dioxide (using a hose suspended by balloons) into the stratosphere. This is what Mount Pinotubo did when it exploded, lowering the Earth’s temperature by about 1°F. The amount of sulfur dioxide involved is quite small, the negative effects are understood, and if we really find the idea of deliberately polluting the atmosphere repugnant, we can simply divert pollution we’re going to create anyway (e.g. from existing coal-fired power plants).
There’s a reason that most environmentalists don’t like this solution, and the core of it is that it doesn’t involve becoming more virtuous in other ways. In fact, it enables us to keep on doing the bad things we’re doing that got us in this problem in the first place — i.e. eating beef, burning fossil fuels, clearing rainforests, and covering huge areas in concrete. I imagine that if, say, the sun were mysteriously increasing its radiation output and we were all going to die unless we did something, injecting sulfur dioxide into the atmosphere would obviously OK. The big problem here is that we’re fixing the outcome of one kind of bad behavior with, in essence, a new form of bad behavior. When might it all end?
The “correct” way to fix the impact of human beings on the earth is depopulation. Anything less than this — recycling, driving a Prius, eating locally grown alfalfa, is just tinkering at the margin. Unfortunately, very few people would like to be part of this solution, so we need to figure out something that works. Yes, the sulfur dioxide solution is “bad”, but the question is do we do something bad now, while we still have most of our biodiversity, coastal real estate, and so forth, or wait until our “less bad” solutions, like trying to convince China and India that they don’t get to have air conditioning or nice cars, fail abjectly and then do it anyway?
The environmental movement is going to have to go back to trying to persuade people to do Good Things, like recycle, because they’re The Right Thing To Do, and not because it will solve climate change.
The big question for me now is what would we do if we needed to raise Earth’s temperature? An ice age would be far more catastrophic than global warming; is there a similar hack we could employ if the sun starts to cool or we go overboard with the sulfur dioxide?
Ars Technica looks at five geoengineering options we have as alternatives to actually cutting carbon emissions, of which one is pumping Sulfur Dioxide into the stratosphere, which is dismissed thus:
They also evaluate a frequently referenced scenario, pumping sulfur dioxide into the stratosphere. Based on current estimates, a doubling of CO2 would add four Watts per square meter to the climate system. Canceling it, the authors calculate, would require the equivalent of a Pinatubo-sized volcanic eruption every other year. We could do it, but it “would lead to several undesirable consequences such as disruption in precipitation patterns and stratospheric ozone, and do nothing to avert the continued absorption of CO2 by the global ocean leading to rising acidity and ecosystem damage.”
The other options aren’t especially convincing either (collecting all our cars’ carbon emissions for example). I’d suggest that changing precipitation patterns is a given whether we do something or not, so it’s probably not a compelling argument on its own. Arguing that it doesn’t solve other problems (because it doesn’t actually remove CO2 from the atmosphere) is also almost beside the point (the same argument applies against the giant space mirrors, but I suppose that wasn’t worth mentioning since the idea is impractical to begin with).
The bottom line is, we’re not going to melt our icecaps and drown because before we get that far we’ll start pumping Sulfur Dioxide into the stratosphere (unless we find a better option). In the mean time, we still need to cut CO2 for its own sake.