The Cartoon Introduction to Climate Change By Bryan Caplan

Stand-Up Economist Yoram Bauman is back with another non-fiction graphic novel, The Cartoon Introduction to Climate Change. As with his previous Cartoon Introductions to Economics (micro and macro), there is much to like. Bauman thoughtfully interweaves physical science and economics. I particularly liked his chapter on scientific uncertainty, and he provides good quick explanations of technological and incentive-based abatement schemes.

Still, this book feels like a missed opportunity. He spends so much time on the climate science that he has little time left for the economics. Perhaps as a result, Bauman neglects many economic insights that climate activists sorely need to hear. Especially:

1. We can use cost-benefit analysis to put climate change in perspective. Multiple leading economists have done cost-benefit analysis of climate change, and as far as I’ve heard even high estimates are a small percentage of global GDP. Maybe I’ve heard wrong, but why didn’t Bauman review the point estimates and confidence intervals of the main studies?

2. Cost-benefit analysis is sensitive to discount rates. The graphic format seems like a great way to teach this vital yet off-putting issue. I immediately picture multiple variants on the Wheat and Chessboard Problem. But the book avoids the topic.

3. Insurance is NOT a no-brainer. Yes, insurance sounds wonderful; that’s Social Desirability Bias for you. But economics tells us that the desirability of insurance depends on the coverage and the cost. That’s why most economists (including famed behavioral economist Matt Rabin) consider extended warranties the height of stupidity. Instead of exposing readers to these inconvenient truths – and possibly trying to surmount them – Bauman repeats the cliche that “It’s a good idea to buy insurance, just in case.” Then he adds, “It turns out that our best insurance policy is to reduce emissions of CO 2 and other greenhouse gases,” without any cost-benefit analysis to speak of. Not good.

4. Leading techno-fixes really do look vastly cheaper than abatement. (see here, here, and here for starters) Bauman has two pages on geoengineering, but hastily dismisses it as not “terribly realistic.” [UPDATE: In the comments, Bauman points out that the “not terribly realistic” claim applies to the idea that geoengineering is a “painless cure-all,” not geoengineering per se. My bad.] But why are eighteen-mile garden hoses less “realistic” than making a serious dent in the world’s expected 250% increase in fossil fuel consumption by 2100?

5. National emissions regulations can have perverse global effects. If relatively clean countries switch to clean energy (via command-and-control regulations, cap-and-trade, pollution taxes, or green norms), fossil fuels don’t vanish. Instead, their world price falls – encouraging further consumption in relatively dirty countries. The net effect? I was hoping Bauman would tell us, but he didn’t even raise the issue.

6. Expressive voting is a big deal. A lot of green activism is clearly expressive – focused on showing commitment rather than improving outcomes. When I was a kid, our family routinely drove to the recycling center to drop off a few bottles. Bauman really should have explained Brennan and Lomasky’s expressive voting model – not to dismiss reformism, but to alert readers to the danger of loudly sacrificing to “help the planet” without verifying the effectiveness of the sacrifice.

As usual, I genuinely liked this Cartoon Introduction. I was entertained and enlightened. But economics offer many lessons that environmentalists need to hear – and Bauman largely fails to teach them these vital lessons.