"Doomsayers were worried about something they called the "greenhouse effect." They said if we didn't reduce our carbon emissions soon, the world would heat up and we would have an ecological catastrophe."<p>Ice age was the preferred senario of the Doomday crowd back then.<p><a href="http://sweetness-light.com/archive/newsweeks-1975-article-about-the-coming-ice-age" rel="nofollow">http://sweetness-light.com/archive/newsweeks-1975-article-ab...</a><p>My grandfather subscribed to Reader's Digest and kept every one of them, in a tall neat stack that reached to the ceiling next to the toilet. There were more from as far back as the 50's in a little cubby hole between the toilet and bathtub. We lived with him for a year in the 80's, and I read a huge number of those; I was convinced the return of the ice caps was imminent, and quite excited about the prospect.<p>I read quite a bit about the nuclear winter debate, and nothing in the popular press about warming until the 90s. I know from what I have read that papers on warming were published as early as the 40s, but in the popular immagination, cooling was expected, and any human effects would be catastrophic cooling from a nuclear exchange.