With a hat tip to John Hodgman, who has pretty well cornered the market on ridiculous solutions to serious problems, I think I've got the answer to climate change: a cap-and-trade program for babies.

As related by the Washington Post, two recent studies have pointed out that the real culprit for global warming isn't cars or coal plants, it's us. There are too many humans on planet Earth, emitting too much carbon. The cheapest cure is contraception, according to a study released last week by the London School of Economics, which points out that each $7 spent on family planning over the next four decades would reduce carbon-dioxide emissions by more than a ton. Achieving the same result with low-carbon technologies would cost at least $32. What's more, a study from Oregon State University concluded that having children (especially American ones, because Americans use vast amounts of energy compared to people from other countries) is the most environmentally damaging decision you can make.

I can see the answer now: You place a cap of one child on every couple, but set up a market to trade child-bearing credits so low-income couples can sell them to those with the means to support big families. It's eugenic-tastic!

OK, maybe not. But the notion is only a little sillier than the solution being promoted by the London School and its study's sponsor, the British-based Optimum Population Trust. Their model for fighting climate change by promoting birth control in the Third World ignores the fact that such programs almost never work.

There are many reasons for the population explosion, but most of them come down to one factor: poverty. Women in poor countries have little education and almost no power over reproductive decisions, so they go from one pregnancy to the next. In places where infant mortality is high, women have a lot of children because some are expected to die. Agrarian societies need children to work the farm. Programs to promote condoms aren't going to change any of this; if you want to lower birth rates, as Jeffrey Sachs and other scholars have pointed out, you have to reduce poverty. That means investing in development for poor countries.

Of course, with development and industrialization come higher greenhouse gas emissions. There's a solution for that, too: Make sure these societies "grow green." To do that, the U.S. and other rich countries have to develop clean-energy technologies, and mass produce them until solar panels and windmills are cheaper for industrializing nations to install than coal-burning power plants.

As Hodgman would say, "Global warming, solved. You're Welcome."

-- Dan Turner

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