70s Cooling Scare transcript
Global warming isn’t the first climate scare in modern times. Back in the 1970s the big thing was cooling.
Leonard Nimoy Clip:
What scientists are telling us now, is that the threat of an ice age is not as remote as they once thought. During the lifetime of our grandchildren, arctic cold and perpetual snow could turn most of the inhabitable portions of our planet into a polar desert.
When it comes to climate, there seems to be violent disagreement about everything from whether arctic ice is vanishing to whether the supposedly settled science around warming was saying the opposite 40 to 50 years ago.
So join me for a Climate Discussion Nexus “Crystal Ball video” on “The 1970s Cooling Scare: Fact or Fiction?”
Many people remember the headlines and pictures from the 1970s warning about a coming ice age, and often bring them up to cast doubt on present-day alarmism about warming.
Others respond yes, there were a few people who worried about it, and a few lurid TV specials like the one with Leonard Nimoy. But on the whole, they say, everybody knew about man-made warming even back then, and the level of agreement on warming today vastly exceeds that on cooling back then.
For example, a Canadian Green Party politician and formerly academic/activist scientist at the University of Victoria, Andrew Weaver, wrote in the Ottawa Citizen that
“Like many of you, I have heard it said that in the 1970s, scientists were saying the world was heading into a new ice age. This has always bothered me because in my 20 years as an active climate researcher, I have never come across a peer-reviewed scientific study that has actually made this claim.”
Weaver conceded that there was popular hype, but said it was just in the media, and never made it into scientific journals.
But global cooling wasn’t a fringe view. In a 1985 study of shifts in expert opinion, two scientists at the US National Center for Atmospheric Research described the 1970s as follows
“This was an interesting time in recent history of climate studies. One could effectively argue that in the early 1970s the prevailing view was that the earth was moving toward a new ice age. Many articles appeared in the scientific literature as well as in the popular press speculating about the impact on agriculture of a 1-2 oC cooling.”
As Alex Epstein notes in The Moral Case for Fossil Fuels,
“In 1975, Nature said, ‘A recent flurry of papers has provided further evidence for the belief that the Earth is cooling. There now seems little doubt that changes over the past few years are more than a minor statistical fluctuation.’”
A flurry of papers. So they were talking about the scientific literature, not just the popular press. Interestingly that same year, Epstein also says, the American Meteorological Society announced that this cooling would increase extreme weather.
Got that? Today the experts say warming will increase extreme weather, and back then they said cooling would increase extreme weather. There’s no winning with these people.
Even if a lot of the discussion was in the popular press, it happened so often and for so long that it must have been drawing on something, including scientific research and data. In his book Global Warning, Trials of an Unsettled Science, author David Solway presents numerous examples:
- In 1971, the Global Ecology network forecast the ‘continued rapid cooling of the earth,’
- In 1975 the New York Times brooded that the earth ‘may be headed for another ice age,’
- In the March 1975 issue of Science, we were informed that ‘the approach of a full-blown 10,000-year ice age [was] a real possibility,’
- And in the July 1975 issue of National Wildlife, C.C. Wallen of the World Meteorological Organization warned that ‘the cooling since 1940 has been large enough and consistent enough that it will not soon be reversed.’”
Kenneth Watt, an ecologist at UC David in California and a key leader of the early environmental movement, declared on Earth Day 1970,
“the world has been chilling sharply for about twenty years. If present trends continue, the world will be about four degrees colder for the global mean temperature in 1990, but eleven degrees colder in the year 2000. This is about twice what it would take to put us into an ice age.”
And popular books took both sides, from Nigel Calder’s The Weather Machine and the Threat of Ice (1974) to Howard A. Wilcox’s Hothouse Earth (1975) and Lowell Ponte’s The Cooling (1976).
One of the most prominent scientists who worried that the mid-20th-century downward trend might continue, even accelerate, with dangerous consequences for the planet was the late Dr. Reid Bryson, who founded the Center for Climatic Research at the University of Wisconsin-Madison in 1962.
Looking at the apparent downward trend in global temperature since the 1940s, Bryson concluded that the Earth was cooling. And he thought humans were affecting temperature in two ways. One was particulate matter pollution from human industrial activity, which causes cooling, and the other was CO2 emissions which cause warming. These two countervailing effects are still regarded as central by modern climate modelers. Bryson thought aerosols were more important, insisting then and throughout his life that CO2 emissions were not having a significant impact.
Another prominent cooling advocate in the early 1970s was the late Stephen Schneider, then a postdoctoral fellow at NASA’s Goddard Institute for Space Studies, and later a scientist at Stanford University. In a 1971 study he, like Bryson, said CO2 was causing warming while aerosols were causing cooling, and that since the impact of CO2 decreases as concentrations rise, aerosols were predominating. Indeed, he warned,
“An increase by only a factor of 4 in global aerosol background concentration may be sufficient to reduce the surface temperature by as much as 3.5 ° K. If sustained over a period of several years, such a temperature decrease over the whole globe is believed to be sufficient to trigger an ice age.”
But Schneider soon changed his mind, saying in 2006 “I was one of the ones who talked about global cooling. I was also the one who said what was wrong with that idea within three years.” And he explained, “Back then this science was so new, so theoretical, it was really hard to sort it out.”
All of which is fair enough. Except the tone of the papers back in 1971 didn’t sound like the science was new and far from being sorted out.
Which is one reason the media swooped in with insufficient caution. Back in 2013 Anthony Watts compiled a list of such newspaper stories in the 1970s. And while alarmists may object that the level of scientific literacy among journalists was appallingly low at the time, the same can surely be said of journalists peddling warming alarmism today.
It can also be said that journalists touting cooling in the 1970s were following scientists’ leads. Hence for instance the Washington Post article dated July 9, 1971 said “U.S. Scientist Sees New Ice Age Coming” and quoted Dr. S.I. Rasool of NASA as saying that,
“In the next 50 years, the fine dust man constantly puts into the atmosphere by fossil fuel-burning could screen out so much sunlight that the average temperature could drop by six degrees…which, if sustained for 5 to 10 years, could “be sufficient to trigger an ice age!”
That same article went on to quote Dr. Gordon MacDonald, a scientist and member of President Nixon’s Council on Environmental Quality, who said that these conclusions point up “one of the serious problems” the U.S. and other nations must soon address. He said the forecast of six degrees cooling “is consistent with estimates I and others have made.”
And around the same time, Dr. Earl Barrett of the National Oceanic and Atmospheric Administration published a study warning that increased particulate pollution “could give rise to a general cooling of serious magnitude.”
So it sure sounds like influential climate scientists were saying human fossil-fuel use was about to trigger a climate disaster unless international action was taken.
A big breakout moment came in December 1972 when scientists George Kukla of the Lamont-Doherty Geological Observatory and RK Matthews of Brown University sent a letter to President Nixon, discussing the result of a climate conference “attended by 42 top American and European investigators” which explicitly warned of cooling.
Specifically, it said “The present rate of the cooling seems fast enough to bring glacial temperatures in about a century, if continuing at the present pace.”
The fact that a whole assembly of top scientists not only reached an agreement on global cooling but proceeded to write a letter warning the US President about the consequences should put to rest once and for all the claim that the idea was never taken seriously.
Geologists have collected enough sea cores to form a detailed history of climate during the last million years.
Dr. James D. Hays in clip:
“Since this theory can precisely predict when ice ages occurred in the past, which can be tested against these deep sea cores, it also can predict when ice ages will occur in the future. From this theory we can say with confidence that we are currently heading toward another ice age.”
Climate scientists now say they never really bought the cooling story. A paper published in the Bulletin of the American Meteorological Society in 2008 by Peterson, Connolley and Fleck (known therefore among insiders as PCF-08) claimed that of 71 peer-reviewed studies from 1965-1979, 7 predicted cooling, 20 were neutral and 44 predicted warming. The study was seized on by warming alarmists as proof of a consensus on warming even in the 1970s.
But one is inclined to wonder about the methodology. After all, if there were only 71 studies over 14 years, just five a year, it seems that nobody had much of an opinion either way. Or maybe the authors just didn’t look very hard.
When researcher Angus McFarlane examined the study’s methodology he noticed that they looked for papers using a very narrow set of search terms. McFarlane looked more broadly and found nearly 200 papers between 1968 and 1976, and by his count 85% saw cooling and just 15% warming.
Despite that, the 1970s cooling scare seems to be going down the same memory hole as the Medieval Warm Period, at least among climate alarmists.
But the fact is that in the 1970s there was a climate panic focused on cooling. A panic that, just like now, got over-hyped by a few activist scientists and further amplified by credulous journalists, and that these groups joined forces to condemn western society, demand more government intervention and central planning, and dismiss any suggestion that humans going about their private business might simply find ingenious ways either to fix the problem or to cope with it.
Then one day the scare ended and all the hype and panic vanished.
Leonard Nimoy as Spock Clip:
Physical reality is consistent with universal laws. Where the lays do not operate, there is no reality. All of this is unreal.
And now the proponents of the same kind interventionist ideas based on the same disturbing linkage between activist scientists and crusading journalists want to forget that that episode ever took place.
But this historian is not going to let that happen.
For the Climate Discussion Nexus, I’m John Robson, and that’s our look into the crystal ball on the 1970s cooling scare.