I must confess that the debate over anthropogenic global warming (climatic change for those of you who’ve shivered through recent summers) has been entertaining. The only thing more amusing than human arrogance is even more human arrogance. Be that as it may, I think the time has come to end the debate.
For the record, human activity obviously affects the global climate. Of course, everything affects the global climate, so that information is not terribly instructive. Where do human influences rank among the various factors? Only the arrogant can provide a definitive answer. However, we should still acknowledge that solar output and orbital dynamics generally have the greatest impact on climatic cycles—an important fact that I will return to shortly.
Since it’s the popular thing to do, I’ll go ahead and assume that anthropogenic climatic change is a bad thing and that we should probably do something about it. Now, though, I will buck the trend and dismiss the mainstream solutions as atmospheric alchemy. Arbitrarily reducing carbon-dioxide emissions over the short term will have a very small effect on global temperatures and will be prohibitively expensive.
Rather than spending hundreds of billions or even trillions of dollars for minimal benefit, why not spend only tens of billions on mitigation efforts and on general economic development? As Bjørn Lomborg has cogently argued, focusing on these goals would have a much greater positive effect at only a fraction of the cost. (Dr. Lomborg is also rightly critical of proposed cap-and-trade schemes, which are ripe for corruption.) Yeah, that’s just wishful thinking.
So let’s spend a bunch of money on prevention, but let’s use science instead of alchemy. That brings me back to the sun, since controlling insolation would be the most cost-effective method of regulating global temperatures. Several “geoengineering” schemes have been proposed to accomplish this goal, but one stands above the rest.
A constellation of solar reflectors in orbit could shade the Earth and reduce global temperatures in a dynamic and very controllable manner. Such a system could probably be developed and deployed for the price of a low-budget manned Mars landing (around $50 billion). Ongoing maintenance of the infrastructure should cost significantly less than that. This would keep us within Dr. Lomborg’s suggestion of cost-effective solutions without the more politically difficult challenge of defeating the institutionalized corruption that stands in the way of his more noble goals.
An orbital sunshade may sound like science fiction, but it makes a lot more sense than mucking about blindly with complex atmospheric chemistry. Insolation could be decreased or increased as needed, allowing for long-term climatic regulation (and other potential benefits). Combined with ongoing pollution controls, a soletta program would provide an elegant and permanent solution to the problem of global warming.
So the debate is over. If you want to control the climate, control the amount of sunlight that reaches the planet’s surface. Doing so would cost a fraction of other less effective solutions.