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What were climate scientists predicting in the 1970s?

What the science says...

Select a level... Basic Intermediate

The vast majority of climate papers in the 1970s predicted warming.

Climate Myth...

Ice age predicted in the 70s

"If you go back to Time Magazine, they actually were proclaiming the next ice age is coming, now it's become global warming… How do you believe the same people that were predicting just a couple decades ago that the new ice age is coming?" (Sean Hannity)

At a glance

If you are aged 60 or over, you may remember this particular myth first-hand. For a brief time in the early to mid-1970s, certain sections of the popular media ran articles describing how we were heading for a renewed ice-age. Such silliness endures to the present day, just with a different gloss: as an example, for the UK tabloid the Daily Express, October just wouldn't be October without it publishing at least one made-up account of the impending 100-day snow-apocalypse.

There were even books written on the subject, such as Nigel Calder's mischievously-entitled The Weather Machine, published in 1974 by the BBC and accompanying a “documentary” of the same name, which was nothing of the sort. A shame, because the same author's previous effort, The Restless Earth, about plate tectonics, was very good indeed.

Thomas Peterson and colleagues did a very neat job of obliterating all of this nonsense. In a 2008 paper titled The myth of the 1970s global cooling scientific consensus, they dared do what the popular press dared not to. They had a look at what was actually going on. Obtaining copies of the peer-reviewed papers on climate, archived in the collections of Nature, JSTOR and the American Meteorological Society and published between 1965 and 1979, they examined and rated them. Would there be a consensus on global cooling? Alas! - no.

Results showed that despite the media claims, just ten per cent of papers predicted a cooling trend. On the other hand, 62% predicted global warming and 28% made no comment either way. The take-home from this one? It's the old media adage, “Never let the truth get in the way of a good story”

Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!

Further details

In the thirty years leading up to the 1970s, available temperature recordings, with a poor global coverage compared to today, implied at times there might be an ongoing cooling trend. At the same time, research was continuing into the building levels of carbon dioxide and their effects on future climate, but the science world of that time was somewhat disconnected, compared to the modern age of instant communication, Zoom and so on.

There were also some notably cold winters scattered through that time, such as the UK one of 1962-63. As a result of these various goings-on, some scientists suggested that the current interglacial period could rapidly draw to a close, which might result in the Earth plunging into a new ice age over the next few centuries.

We now know that the smog that climatologists call ‘aerosols’ – emitted by human activities into the atmosphere – caused localised cooling closest to the areas where most of it originated. Smogs constitute a deadly health hazard and governments acted quickly to clean up that type of pollution: highly visible (unlike CO2), it was hard to ignore. Once largely removed, its effects no longer influenced Northern Hemisphere temperatures, that have steadily climbed since around 1970.

In fact, as temperature recording has improved in coverage, it’s become clear that the cooling trend was indeed localised – it was most pronounced in northern land areas. Other places around the world revealed a different story. Furthermore, at the same time as some scientists were suggesting we might be facing another ice age, a significantly greater number - approximately six times more - published papers indicating the opposite - that we were warming. Their papers showed that the growing amount of greenhouse gases that humans were putting into the atmosphere would cause much greater warming – warming that would exert a much stronger influence on global temperature than any possible natural or human-caused cooling effects.

By 1980, with northern hemisphere smogs a distant memory, the predictions about ice ages had ceased, at least among those working on the science, due to the overwhelming evidence for warming presented in the scientific literature (Peterson et al. 2008). Unfortunately though, the small number of predictions of an ice age were far more 'sticky' than those of global warming, so it was those sensational 'Ice Age' stories in the 1970s popular press that so many people tend to remember. Sticky themes sell papers. Today of course, with 40+years more data, far better coverage and a far bigger research community, we've reached a clear scientific consensus: 97% of working climate scientists agree with the view that human beings are causing global warming.

Last updated on 8 March 2024 by John Mason. View Archives

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Further reading

Denial101x video

Related video from DENIAL101x - Climate science in the 1970s


Fact brief

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Comments 1 to 25 out of 145:

  1. But the idea that we will go into another glaciation is far sounder science than is this new and basically baseless stuff. We always have in the past. This planet is currently hard-wired with a one way catastrophic cooling bias. The case that we will have another glaciation is basically cut and dried. We have the capacity to cool the earth. We have no such capacity to warm the earth. In order to avoid another glaciation we ought to be looking at ways to hose down volcanic aerosols or something. Certainly we need to build up our nuclear energy production capacity. And our hydrocarbons as well.
  2. Ice ages cannot be explained without the GHG feedback. The same science that tells us this, tells us we are heating up the planet.
  3. The claim by Peterson that there were only 7 papers in the 1970s predicting cooling is just ridiculous. Anyone can check this with a quick look at Google scholar. Here are two examples they have missed, but there are many more. Return of the ice age and drought in peninsular Florida? Joseph M. Moran, Geology 3 (12): 695-696 (1975) Convection in the Antarctic Ice Sheet Leading to a Surge of the Ice Sheet and Possibly to a New Ice Age T. Hughes, Science Vol. 170. no. 3958, pp. 630 - 633 (1970) What is strange is why people attempt to re-write recent history in this way, when their claims can so easily be disproven. Where did all the stories in the papers, TV and magazines come from? Were they all just fabricated? No of course not, they came from scientists who made suggestions (like the above 'possibly to a new ice age') which were then hyped and exaggerated by the media. Much the same thing is happening now with the global warming scare.
  4. Um, for one thing Moran was writing about _Florida_ cooling, not _global_ cooling. I guess you'll need to relax your search criterion for "global cooling" a whole lot to prove that scientists did predict cooling... "they came from scientists who made suggestions (like the above 'possibly to a new ice age') which were then hyped and exaggerated by the media. Much the same thing is happening now with the global warming scare." Yeah, "much of the same thing" in the sense that the "media" is artificially inflating the voice of the global warming "skeptics".
  5. frankbi Read the media articles, they are almost always alarmist. Those that have comment sections often disappear after someone disproves the article. I have seen this on CBS, ABC and LiveScience quite a few times. Then there is the BBC.
  6. PaulM, You bemoan people attempting to [quote]‘re-write recent history’. However, reporting the facts does not amount to ‘rewriting history’! The people actually responsible for the rewriting of history are not AGW fanatics, but people politically or ideologically aligned to industry and typically funded directly or indirectly by the fossil fuel funded denial industry. Peterson et al. 2008 have merely attempted to establish the facts and set the record straight. The fact that you may have identified two additional relevant papers and claimed there are ‘many more’, which may or may not support your pet theory, does not invalidate their research. It seems probable that any additional papers fitting the various search criteria will be distributed in much the same way as the papers already listed, unless there is a very good reason why they should not be included.
  7. Quietman You are repeating the deceitful alarmist allegations made repeatedly by skeptics From Scientists add to heat over global warming by S. Fred Singer Washington Times, May 5, 1998 “But this exaggerated concern about global warming contrasts sharply with an earlier NAS/NRC report, "Understanding Climate Change: A Program for Action." There, in 1975, the NAS "experts" exhibited the same hysterical fears—-this time, however, asserting a "finite possibility that a serious worldwide cooling could befall the Earth within the next 100 years." The 1975 NAS panel claimed to have good reason for their fears: Global temperatures had been in steady decline since the 1940s. They considered the preceding period of warming, between 1860 and 1940, as "unusual," following as it did the "Little Ice Age," which had lasted from 1430 to 1850.” You will note that the terms ‘exaggerated’, ‘hysterical fears’ and ‘fears’ are used. There are a number of other changes too that render the use of quotes highly questionable. 1975 US National Academy of Sciences/National Research Council Report UNDERSTANDING CLIMATE CHANGE: A program for action Strangely, From the foreword (by V E Suomi, Chair of the US Committee for GARP): "..,we do not have a good quantitative understanding of our climate machine and what determines its course. Without the fundamental understanding, it does not seem possible to predict climate..,". From the introduction "Climatic change has been a subject of intellectual interest for many years. However, there are now more compelling reasons for its study: the growing awareness that our economic and social stability is profoundly influenced by climate and that man's activities themselves may be capable of influencing the climate in possibly undesirable ways. The climates of the earth have always been changing, and they will doubtless continue to do so in the future. How large these future changes will be, and where and how rapidly they will occur, we do not know". Not much evidence of hysteria! It would seem that the allegations of exaggeration and hysteria were complete fabrications introduced by Singer. The measured and cautious language of the National Academy of Sciences has been entirely born out.
  8. Re: "You are repeating the deceitful alarmist allegations made repeatedly by skeptics" No, I am not repeating anything. My statement is purely from personal experience. I tried again this morining, after reading your reply, to go back and see if some of the alarmist articles were still there. Most were gone. I checked back through January - gone. What few skeptical articles I had read are still there. I may be ignorant about many subjects but I am not stupid. Those articles were intentionally pulled when proven incorrect. Here are the few that have not been deleted: The rhetoric of climate and slavery Climate change 2007 - a year in review Trees absorbing less CO2 as world warms, study finds Acidic seas may kill 98% of world's reefs by 2050 Deniers of global warming harm us Global warming to trigger volcanic eruptions
  9. These articles all present a case for either natural warming or non-CO2 forced AGW, or simply that the alarmist claims don't quite cut it. Water Vapor Feedback Is Rapidly Warming Europe About the coral reefs: Coral Reefs May Be More Resilient Than Expected "The deniers' fallback position is to argue that what is happening is due not to human intervention but some sort of natural cycle." During the last centuries human methane emissions artificially increased CH4 concentrations to approximately 1750 ppbv: Current Spike In Atmospheric Methane Mirrors Early Climate Change Events NASA Studies How Airborne Particles Affect Climate Change "Tropical deforestation currently accounts for roughly one-fifth of the global emissions of carbon dioxide, the most important human-derived greenhouse gas, Gurney said." Researchers Propose Way To Incorporate Deforestation Into Climate Change Treaty "Whilst rising air temperatures are believed to be the primary cause of recent dramatic disintegration of ice shelves like Larsen B, the new study suggests that the ocean may play a more significant role in destroying them than previously thought." Antarctic Ice Shelf Retreats Happened Before Antarctic Deep Sea Gets Colder My point being that healthy skepticism leads to better understanding of the big picture.
    Response: I'll leave this comment up as there are few links there I wasn't previously aware of. But from now on, I'm taking a zero tolerance policy on comments that post a bunch of links not related to the topic. I know its a bit more work but please post any links on the relevant page.
  10. Sorry John I was replying to ScaredAmoeba "You are repeating the deceitful alarmist allegations made repeatedly by skeptics" Attempting to show that not all skeptical arguments are denials or harmful. If you prefer to delete it thats OK by me, it's your blog.
    Response: Nah, I'll leave it up. One of my pet peeves when having online discussion about global warming is when someone just posts a whole bunch of diverse links to a wide range of topics - it essentially shuts down the discussion because it's not practical to post a reply addressing each link. More constructive debate keeps to the topic at hand. I don't think you were necessarily trying to do this but for future reference, those links would be more effective posted on the appropriate page. Plus from my point of view as webmaster, I like the comments section to be relevant and useful to readers.
  11. The side argument over deceit aside, I would like to point out that the scientist who started the cooling fright in the 70s actually has not changed his position. Reading his work indicates that there should be an upcoming glacation regardless of any warming but the timing was and still is unknown. The panic was caused by the media reading timing as immediate into his work.
  12. Re #3: It's easy to be misled by the titles of papers. The examples you've asserted as supporting a 1970's perspective of global cooling don't actually do so. Your second article sounds like it does: Convection in the Antarctic Ice Sheet Leading to a Surge of the Ice Sheet and Possibly to a New Ice Age T. Hughes, Science Vol. 170. no. 3958, pp. 630 - 633 (1970) But it's just a potentially misleadingly worded title. If you read the paper it's got zero relevance to a possibility of a "new ice age" in the near (i.e. "near" from a 1970 perspective). It's about the GENERAL nature of ice Antarctic ice sheet advance that might (within a particular "surge" theory) be linked to the glacial cycles within the Pleistocene. So it's about how glacial periods might in general occur. That's very clear from reading the paper. It's also evident just from reading the abstract: abstract: "The Antarctic surge theory of Pleistocene glaciation is reexamined in the context of thermal convection theory applied to the Antarctic ice sheet. The ice sheet surges when a water layer at the base of the ice sheet reaches the edge of the ice sheet over broad fronts and has a thickness sufficient to drown the projections from the bed that most strongly hinder basal ice flow. Frictional heat from convection flow promotes basal melting, and, as the ice sheet grows to the continental shelf of Antarctica, a surge of the ice sheet appears likely." So it's a theoretical study of a mechanism for ice sheet advance during glacial cycles. It doesn't address the possibility of any such event during the current Holocene, and has nothing to do with 1970's scientific perception of global warming or cooling or any such thing. Likewise it's understandable why Peterson et al. didn't include your other paper as a "cooling"/Ice Age" one: Return of the ice age and drought in peninsular Florida? Joseph M. Moran, Geology 3 (12): 695-696 (1975) Although the title (and the rather odd abstract) might suggest that the paper is about the "return of the ice age", the question mark highlights the fact that the author is rather equivocal over such a conclusion. Here's how he ends his (very brief) note: "While there is an interesting parallel between recent and late-glacial events in the tropics, no clear cause-effect relation has been established between the current hemispheric cooling trend and precipitation trend in peninsular Florida. Also, even if a linkage were established, there is no certainty that the hemispheric cooling trend will not reverse itself in a few years. Rather than portraying a bleak future for Florida’s water supply, therefore, the observations presented here should serve as stimuli for further monitoring and research to promote understanding of the controlling atmospheric phenomena." In other words, the paper relates to precipitation trends with potential implications for water supply in Florida, and the author indicates that there isn't any necessary relation between cooling and precipitation trends and indicates anyway that the cooling trend might reverse itself. So neither of your suggestions - absolutely not the first one which is totally irrelevant to 1970's perspective on cooling/warming or otherwise, - nor the second one can be taken to support the notion of any 1970's scientific perception of global cooling (by the criterion that Paterson et al. set of a paper with a clear projection of climate change or discussing an aspect of climate forcing relevant to time scales of decades or centuries). Morgan's short note doesn't come to any conclusion - the "cooling" "...might reverse itself in a few years".
  13. I was struck by this week's skeptic article (by David Deming in "The American Thinker"), [] finding it both laughable and inspiring, and it drew me back to here. One thing that surprised me a bit was Deming's claim that we don't know what causes ice ages. I thought it was Milankovitch cycles mostly (Deming says Ike Winograd disproved that). With the google I only found a Wunsch abstract [] that says orbital changes only explain 20% of the variance in climate records studies. Anyway, I'm curious to learn more about our understanding of ice ages.
  14. GMG #1: You SAY it is 'sounder science', but you ignore all the evidence to the contrary presented in this article and many others on this site. No, belief in impending glaciation is NOT 'sounder science'. Nor is it "sounder science" to argue as you do, that it has always happened that way. On the contrary: the SOUND science recognizes that things are no longer going to happen "as they always have happened". Now we really have made a large enough change to break the age-old pattern -- for the worse.
  15. This Basic Version is one of the better ones written so far. It has much better flow as we read it. One idea logically follows after the other, leading naturally to a sound conclusion. Well and good: but you knew there was a 'but' coming, didn't you;)? That 'but' is: "but the sentences are too long for our target audience". To remedy this, I suggest some strategic application of metonymy, synecdoche and ellipsis to tighten things up. So, for example, we can do much better than "As a result some scientists suggested that the current inter-glacial period could rapidly draw to a close, which might result in the Earth plunging into a new ice age over the next few centuries." We can instead, say "So some scientists suggested that the current inter-glacial could draw to a rapid close, starting a new ice age over the next few centuries". (we really don't need to specify that it is the Earth we are talking about). Similarly, "This idea could have been reinforced by the knowledge that the smog that climatologists call ‘aerosols’ – emitted by human activities into the atmosphere – also caused cooling." can also be improved by replacing with: "About the same time, climatologist learned that 'aerosols' (small particles resulting from human activities) can cause cooling. This may have have encouraged the idea that a new ice age was coming". One final note: here in the States at least, we use "it's" as a contraction for "it is". We never use it for "it has". I don't know about the state of the language Down Under, but if the target audience is here in the US, the use of "it's" to mean "it has" will sound strange to too many in your target audience.
  16. If you want to read the Shackleton paper yourself, instead of taking what William Connelly says at face value, you can read the abstract here: "Science. 1976 Dec 10;194(4270):1121-32. Variations in the Earth's Orbit: Pacemaker of the Ice Ages. Hays JD, Imbrie J, Shackleton NJ. Abstract 1) Three indices of global climate have been monitored in the record of the past 450,000 years in Southern Hemisphere ocean-floor sediments. 2) Over the frequency range 10(-4) to 10(-5) cycle per year, climatic variance of these records is concentrated in three discrete spectral peaks at periods of 23,000, 42,000, and approximately 100,000 years. These peaks correspond to the dominant periods of the earth's solar orbit, and contain respectively about 10, 25, and 50 percent of the climatic variance. 3) The 42,000-year climatic component has the same period as variations in the obliquity of the earth's axis and retains a constant phase relationship with it. 4) The 23,000-year portion of the variance displays the same periods (about 23,000 and 19,000 years) as the quasi-periodic precession index. 5) The dominant, 100,000-year climatic [See table in the PDF file] component has an average period close to, and is in phase with, orbital eccentricity. Unlike the correlations between climate and the higher-frequency orbital variations (which can be explained on the assumption that the climate system responds linearly to orbital forcing), an explanation of the correlation between climate and eccentricity probably requires an assumption of nonlinearity. 6) It is concluded that changes in the earth's orbital geometry are the fundamental cause of the succession of Quaternary ice ages. 7) A model of future climate based on the observed orbital-climate relationships, but ignoring anthropogenic effects, predicts that the long-term trend over the next sevem thousand years is toward extensive Northern Hemisphere glaciation. PMID: 17790893 [PubMed] LinkOut - more resources "
  17. cjshaker, number 7 in your list states : A model of future climate based on the observed orbital-climate relationships, but ignoring anthropogenic effects, predicts that the long-term trend over the next sevem thousand years is toward extensive Northern Hemisphere glaciation. Does William Connelly interpret this paper a different way ?
  18. Did scientists predict an impending ice age in the 1970s? It was most certainly communicated they did.
  19. By whom? Popular daily newspapers & weeky magazines, e.g. Newsweek, are not reliable communicators of the accumulated scientific knowledge.
  20. "In Search Of"? Seriously? (-chuckles aloud-) BP, you missed your calling in life. (Guilty pleasures admission: the episodes on Mars dying from climate change [Season 1, Episode 9] and on the search for Atlantis [Season 1, Episode 10] are my favorites) For all you Leonard Nimoy fans (and you know who you are): Thanks for the chuckle, The Yooper
  21. I guess this is the correct thread to post my anecdotal evidence. I am really shocked by the display of revisionist history in the "What the science says" section. I have a BS in meteorology, 1979-1982. Some of the classes included physical meteorology, planetary atmospheres, air pollution, taught by both American (one at NASA) and European professors. We were taught that the Earth was in the last phase of an inter-glacial period and through a process called instantaneous glaciation, we could plunge into another ice-age within a few hundred years. We were taught that the runaway greenhouse effect occurred on Venus because the atmosphere never reached saturation vapor pressure and eventually all of the water boiled off into space. Here on Earth we were lucky, water condensed out to form the oceans, stabilizing the climate. Nothing about Anthropogenic Global Warming (AGW) being a threat, sorry, I wasn't taught that. I asked a colleague this morning what he was taught in the 70's and he said the same thing, global cooling. In 1981 I had chance to take a summer class with Dr. James Hansen in planetary atmospheres but didn’t get in, made first alternate. Maybe Dr. Hansen would have introduced me to the concept of AGW but since I could not attend I can’t tell you what he taught in that summer class.
  22. @thepoodlebites #21 In order it to be complete anecdotal evidence, could you tell the name of the institution you did study at? name of some professors and/or heads of department? name of a couple of books you may have used in the subjects you named, and still keep in your bookshelves? and succinctly what did you do with your degree in meteorology (professionally speaking)? If you want, I can explain why is this very important. Thanks in advance.
  23. #21: "Nothing about Anthropogenic Global Warming (AGW) being a threat, sorry, I wasn't taught that." Perhaps your university, like many, suffered from a conservative bias among faculty. Some university geology departments taught 'continental foundering' for years as evidence for plate tectonics piled up. That doesn't prove anything about the current state of the science. But the signs were there: Hansen published a paper on warming in 1981; the predictions reflected the early nature of the science, but they were substantially correct. See also this article with links to earlier publications and a link to a video from 1989.
  24. @21 thepoolbites: You've introduced a term I had never heard of before, "instantaneous glaciation", which seemed odd. If you search Google for it there are only 179 matches - two of which are actually links to your usage here. If you search Google Scholar you find only 15 matches, if you search Google Ngrams, it doesn't appear at all. The term is, for all practical intents and purposes, not used. I suspect you are mis-remembering a 30 year old class. Next, the assertion made in this article is that the majority of predictions in the 1970s were for warming, not cooling. That is not a question that an anecdote can answer. The writer demonstrated his thesis - the vast majority of papers in the field from the mid-1960s through the 1970s predicted that warming, not cooling, was in our future. Three to four decades later, it is clear they were absolutely correct.
  25. Maybe first we could wait until thepoodlebites #21 provides more information. By the way, thepoodlebites, were your colleague taught in the same institution? the same grade? can you ask him/her? Not that I think that muoncounter's and snowhare's comments are nothing but excellent, but I think that the first comment would be better once thepoodlebites provide basic information, and the second one is excellent once no information is provided. We have to consider that the success of -10% more visitors each month- is going to drive more people of every kind and with that in mind it would be not advisable to engage in debates when incomplete information is provided without first ask the commenter to provide whatever in good faith he or she may have considered unnecessary.

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