Global warming—the essential argument

The other day I had a conversation (argument) about global warming with my neighbour across the hall. He is adamant that we are not causing it. The science doesn't impress him. That climatologists are unanimous on the issue is, in his view, nothing but reason to be suspicious.

This denial of science is in the grand old tradition of denying that the Earth rotates around the sun or that evolution explains life on the planet. The difference is that it never really mattered how many people rejected those ideas whereas with global warming it matters very much. If not enough people recognize this reality and push their politicians to deal with it, humanity has a grim future indeed. And unfortunately there are powerful forces arrayed against the truth. The Trump administration continues to ramp up its attack on climate science; elements in Brazil's new government insist the global warming issue is a Marxist plot; the European far right, worried about the success of the Greens in the recent EU elections, doubles down on climate change denial; and right here in our heartland of Alberta, the new government busily dismantles one of the country's better climate change programs.

Trying to convince all these people that we should act on the best scientific advice is futile. The only approach that might work is to strip the issue down to its essence, down to the bare bones. Believe in anthropogenic global warming or don't. It doesn't matter. Flip a coin. Just recognize the essential truth. If we act on the warnings of the climatologists and they're wrong, there's little or no downside. We just wind up with a cleaner, greener planet. But if we don't act, and they are right, the downside is a cascade of catastrophes that could bring modern civilization down around our ears. Even the most zealous denier cannot sensibly ignore that logic.