Now that Al Gore's An Inconvenient Truth has won an Oscar and global warming has become a household concern, it's easy to forget that just 30 years ago, people were worried about the exact opposite happening. In 1975, Newsweek ran an article entitled "The Cooling World" [PDF] that foretold the decimation of agricultural productivity based on a dramatic decrease in the Earth's temperature.
"The only thing to worry about global warming is the damage that can be done by worrying. Why are some scientists worried? Perhaps because they feel that to stop worrying may mean to stop being paid."
Actually, it's not that easy to forget, as deniers of global warming continue to bring up the bogus "global cooling" threat as a reason we shouldn't worry about climate change in general. Just last year, James Inhofe, then the chairman of the Senate Committee on Environment and Public Works, used quotes from the Newsweek article in a speech from the Senate floor. He blamed the media for current concerns about climate change, stating that "Breaking the cycles of media hysteria will not be easy since hysteria sellsit's very profitable." (He also got in a dig at Al Gore's film, calling it "one of the slickest science propaganda films of all time.")
The article has been so politicized that in 2006, Newsweek felt it necessarymore than 30 years after the factto issue a quasi-correction for their story on global cooling, stating that "the tools scientists have at their disposal nowvastly more data, incomparably faster computers and infinitely more sophisticated mathematical modelsrender any forecasts from 1975 as inoperative as the predictions being made around the same time about the inevitable triumph of communism."
But what about those scientists who were quoted making predictions about a coming ice age? Do they disavow their research? Most of the scientists quoted in the Newsweek article have died, but Gelf was able to get in touch with one who's still analyzing the data. George Kukla, 77, is a special research scientist for the Earth Institute at Columbia University. His research was referenced in the Newsweek piece, which stated that "satellite photos indicated a sudden, large increase in Northern Hemisphere snow cover in the winter of 1971-72." In a New York Times piece [PDF] later that year titled "Scientists ask why world is changing; Major cooling may be ahead," Kukla is paraphrased as stating that the trend towards cooling will continue for the next 4,000 years.
Gelf caught up with Kukla over email to discuss the Newsweek article, how the recent warming trend fits into his theory, and the politicization of the weather. The following interview has been edited for clarity. Even 30 years after the Newsweek article, Kukla still sees an ice age coming.
Gelf Magazine: Did you hear about the 1975 Newsweek article "The Cooling World" when it came out? Did you know your research was being referenced in it? How do you feel about that?
George Kukla: No, I didn't know about the article, so the first three of your questions are irrelevant.
GM: What do you think about the article now?
GK: Well, that the basic observation about the cooling in the Northern Hemisphere between 1945 and the mid-seventies was correct. However, the projection of the cooling into the immediate future was mistaken. Note that none of us expected uninterrupted continuation of the trend. The knowledgeable climate students know that the global climate works in cycles. The relatively short cycles happen to be about 60 to 80 years long, out of which one half goes up and the other half down. Right now the Northern Hemisphere appears to be at the turning point of the warming branch. Just wait!
GK: Well, I think that neither the "bad boys" nor the "good guys" know what is going on, and even worse, would be able to comprehend it. (This is not to claim that I am absolutely sure about it).
However, this is how I see it:
Yes, the globe is warming, so we do have "global warming" indeed! It proceeds in up and down cycles, but the general trend is up, no doubt about it.
What is happening is very similar to the time 115,000 years ago, when the last glaciation started. It is difficult to comprehend, but it is really so: The last glacial was accompanied by the increase of a really averaged global mean surface temperature, alias global warming.
What happened then was that the shifting sun warmed the tropics and cooled the Arctic and Antarctic. Because the tropics are so much larger than the poles, the area-weighted global mean temperature was increasing. But also increasing was the temperature difference between the oceans and the poles, the basic condition of polar ice growth. Believe it or not, the last glacial started with "global warming"!
The shifts of solar orbit today are about two to three times weaker than in the last glacial, or by the way, in the last 400,000 years. So, on that basis, we have little to worry. However, to expect today a possible complete melting of the Antarctic and Greenland ice sheets is entirely out of place.
So my advice: wait and see what happens! In no more than 50 years we'll see who's right.
GM: You said that "neither the "bad boys" nor the "good guys" know what is going on, and even worse, would be able to comprehend it." Does that mean we shouldn't worry about it? Why are all of these other scientists worried?
GK: The only thing to worry about is the damage that can be done by worrying. Why are some scientists worried? Perhaps because they feel that to stop worrying may mean to stop being paid.
GM: I'm afraid to ask this question: What do you think of the way the media has covered both "global cooling" and "global warming"?
GK: I just think that they need to make money and they seem to know best how to do it. You can't blame them for that.
GM: In most cases, it seems like global warming and global cooling are separated by political lines. Are you surprised that the issue is so politicized?
GK: Am I surprised that global warming and cooling are separated by political lines? NOT at all. Especially if media seem to be helping a lot.
GM: What effects do carbon-dioxide emissions have on the cooling and warming cycles? Could they throw it out of balance, and what would that look like?
GK: Good question! The CO2 certainly has an influence. For instance, it appears that already now, with still relatively low concentrations, it may have a significant warming impact on the night [temperature] minima. And because the usual way to determine the daily mean is as the average of the daily minimum and maximum, here we go! But it is difficult to be sure: more clouds can do the same.
GM: In 2000, you told the Columbia University News that you believed that global warming was merely a blip before a coming ice age. Do you still agree with that?
GK: That article is principally still OK. Only then I didn't know that the glacials, all glacials by the way, started by global warming. (Understood as area-weighted average global mean temperature, that is.) So the title of that Columbia article today would have been: "Evidence of approaching ice age is in accelerated global warming." [Editor's note: The current subtitle of the piece reads, "Sees Evidence of Approaching Ice Age Despite Global Warming"] Also, I didn't stress the exceptional weakness of currently ongoing astronomic changes as compared to the last three glacial cycles. No doubt that we have about 10,000 or even possibly 20,000 years still ahead before the major ice advance can start. What we should watch now is the El Niño and La Niña. They can tell.
GM: There's a general consensus among scientists (or at least scientific representation in the media) that man is responsible for global warming. What do you think about that? Do you agree?
GK: What I think is this: Man is responsible for a PART of global warming. MOST of it is still natural.