You can’t say I wasn’t warned. When I was in the sixth grade (that’s in 1950), we got the Saturday Evening Post in the mail once a week—and so I probably read their article, "Is the World Getting Warmer?"

About the time I started high school in 1953, both Time magazine and Popular Mechanics were running warnings by the infra-red heat expert Gilbert Plass. I probably read them too.

Then I likely forgot all about the problem, since the Cold War and bomb testing seemed much more scary than any drip-drip-drip scenario—one even slower than dry rot from an unrepaired roof leak.

But five years later, when I was a physics major at Northwestern University, there was a weekly film series in the engineering auditorium and one cold Friday night, among the short subjects preceding the main feature, I saw a short documentary on global warming directed by Frank Capra. (You can view it on YouTube’s archive and marvel at the old "straight man" attempts to provide comic relief; the diagnosis and prognosis were, however, right on.) Then in my third year of college, I read Plass’ 1959 article in Scientific American, "Carbon Dioxide and Climate."