We Were Wrong About Global Cooling, but We're Right About Global Warming

Back in the 70's the hot threat in the world of climate science was global cooling, and of course, we were all going to die. But then a few years later, everybody forgot global cooling and the hot climate worry became global warming. So how did everybody get it so wrong and what's makes us believe they're right now?

Got me, but Newsweek wants us all to believe that despite their past errors, they've got it under control now and we should all be worried about global warming:

How did NEWSWEEK—or for that matter, Time magazine, which also ran a story on the subject (global cooling) in the mid-1970s—get things so wrong? In fact, the story wasn't "wrong" in the journalistic sense of "inaccurate." Some scientists indeed thought the Earth might be cooling in the 1970s, and some laymen—even one as sophisticated and well-educated as Isaac Asimov—saw potentially dire implications for climate and food production. After all, Ice Ages were common in Earth's history; if anything, the warm "interglacial" period in which human civilization evolved, and still exists, is the exception. The cause of these periodic climatic shifts is still being studied and debated, but many scientists believe they are influenced by small changes in the Earth's orbit around the Sun (including its "eccentricity," or the extent to which it deviates from a perfect circle) and the tilt of its rotation. As calculated by the mathematician Milutin Milankovitch in the 1920s, these factors vary on interlocking cycles of around 20,000, 40,000 and 100,000 years, and if nothing else changed they would be certain to bring on a new Ice Age at some time. In the 1970s, there were scientists who thought this shift might be imminent; more recent data, according to William Connolley, a climate scientist at the British Antarctic Survey who has made a hobby of studying Ice Age predictions, suggest that it might be much farther off.

Blah, blah, blah. Bottom line, they fell for the absolute worst case scenerio in 1975 and they're probably repeating their mistake today. Those scientists who believe that it's the changes in Earth's orbit and the relative power output of the sun that affects our temperatures are much more likely to be right, but that puts them on the wrong side of the argument because that takes out the evil human element, and that's what keeps funding their grants.

Newsweek is feeling a little sensitive about their 1975 report because it keeps getting thrown back in their face as evidence that the "experts" really don't know what's going on or how to stop it. Hearing a U.S. Senator quote their old report on the Senate floor last week triggered this latest face-saving article. Why should we believe them now?

My guess is that in 20 or 30 years there will be another Newsweek article which basically says "yeah, we screwed that one up too".