The 1970s Global Cooling Scare (and how the warming scare could not have happened without it)

Guest essay by Bernie Lewin

This is the second post drawing on themes raised in the book Searching for the Catastrophe Signal. See a previous post on WUWT here.

Forty-five years ago today, two geologists penned a letter to the president of the United States warning that the rocky decent into the next ice age might have already begun.

The year 1972 remains infamous in the annals of meteorology for extreme weather events all around the globe. Towards the end of that year, in a letter dated 3 December 1972, two geologists George Kukla and Robert Matthews warned President Nixon that…

…a global deterioration of climate, by order of magnitude larger than any hitherto experienced by civilized mankind is a very real possibility and indeed may be due very soon.

When geologists say ‘very soon’ it is wise to hesitate, but Kukla and Matthews were quick to remove any suggestion that they might be talking only in terms of millennia-metered geological time. ‘The present cooling now underway in the Northern Hemisphere’, they went on to explain, ‘could be the start of this expected shift’. In other words, it looked every bit like the stable mild climate of recent millennia has already ended.

It is hard to find a single document more instrumental in the history of post-War climate anxieties than this letter. It would trigger a series of events that resulted in the first coordinated program of climate research in the United States and then at the United Nations. It also set the stage upon which the global warming scare would subsequently be launched with demands for a global response.

Today, as the 1970s global cooling scare starts to pass beyond living memory, it is widely misunderstood. This is especially in its relationship with the subsequent scare over global warming. Warming skeptics will often talk up the scare, emphasizing how meteorologists have flipped from cooling alarm to warming alarm. In fact, few meteorologists were involved in the cooling scare, while there were very few scientists of any variety who raised alarm over cooling and then switching to alarm over warming.

On the other side of the current debate, warming alarmists often play down the cooling scare as little more than a press beat up (e.g., see here). This is also wrong. In fact the cooling scare was promoted by scientists on scientific evidence. Sure, the press did their usual job of playing up fears, but there was often a measure of circumspection thrown in. From the scientific point of view, the main problem with the press coverage was that meteorological speculation on the return of the Little Ice Age was confused with geologists’ warnings about a return of the bigone.

The time has come to clear up the confusion and give the cooling scare its proper place in history. The summary that follows starts with thematic introductions to the context in which the cooling scare arose. It finishes by showing how the cooling scare set the stage for an easy transition to a warming scare. For a fuller account, complete with references, see the early chapters of Searching for the Catastrophe Signal.

Meteorologists warned of a return to the Little Ice Age.

By 1961 there was general agreement among historical climatologists that the 20th century warming trend across northern mid-latitudes had ended around 1940. A series of severe winters in the early 1960s raised concerns that a cooling trend was again settling in across Europe. This led some to warn that Europe may be returning to the prevailing weather patterns of the Little Ice Age, which had had a variable impact across Europe during the previous four centuries.

The weather extremes of 1972-3

In 1972 climate change broke into the public discourse as it never had before. On top of evidence for a cooling trend came not only a strong El Niño but also other weather extremes that are not directly associated with that phenomenon. The extremes were as much to do with precipitation as temperature. Some regions experiencing extraordinary flooding rains while the effects of a third year of drought south of the Sahara was soon broadcast with all its horror into living rooms across the wealthy north. There had always been talk that forest clearing and over-grazing caused or exacerbated local droughts, but, during the 1970s, droughts and all sorts of other weather extremes would be linked to the speculation about a natural global climate shift in the direction of cooling.

Little interest in the human influence

From the late 1960s, the geology-trained US climatologist Reid Bryson was warning of the cooling effect of dust continually thrown up into the troposphere by human industry, especially agriculture. This and other mechanisms of human influence on global cooling did garner some interest, but throughout the 1970s the overwhelming concern with global climatic changes remained with changes that were entirely natural.

Population explosion, resource depletion and the US energy crisis

From the late 1960s, concerns about the post-War population explosion involved concerns about the ability to produce enough food to feed everyone. The associated exponential increases in demand for non-renewable natural resources led to concerns about the absolute depletion of these resources, especially energy resources. In 1973, the Arab oil embargo targeted the USA and some of its allies, triggering the US ‘energy crisis’, which continued through to the end of the 1970s as a mostly socially constructed phenomenon, but real all the same. Meanwhile, a series of extreme winters in North America saw concerns over climatic change reinforce energy supply anxieties, especially when heating oil was in short supply. All these factors contributed to a prevailing public anxiety over food and energy security that was seen to be exacerbated by a cooling trend in the climate.

We should note here that the US energy crisis peaked in 1979 before a subsequent crash. This is important because it coincided with a transition from cooling to warming alarm. The year 1979 brought the Iranian Revolution, which caused the oil price to quadruple again. It also brought the Three Mile Island nuclear accident which presented a turning point for the nuclear power industry. It is true that the 1960s expansion of nuclear electricity production had already started to falter around the time of the oil embargo due to cost blowouts and construction delays. However,  an overwhelming response to the 1979 reactor emergency in Pennsylvania brought public safety concerns to such heights that the anti-nukes movement started to look like it was winning. And still in 1979 we find climatologists continued to report a cooling trend evident in the record. But then it was all over. Energy-climate anxiety rapidly dissipated after Jimmy Carter failed to win a second term, after the oil prices fell and after the climate started to show signs that four decades of cooling might be over.

A revolution in Quaternary Geology

The one great scientific advance that contributed to the 1970s cooling scare was a revolution in Quaternary geology. Until the late 1960s, it was generally agreed that there had been four recent glaciations, however their timing was largely unknown due to inadequate dating techniques. As the new dating technology was brought into play, it revealed that since the last geometric reversal, around 700,000 years ago, there had been no less than 8 cool/warm cycles. It also showed that cool was the norm. Indeed, the whole Quaternary period (i.e., the last 2.5 million years) is best described as an ice age punctuated by brief ‘interglacial’ warm ‘epochs’. These interglacials appeared like clockwork on a 100,000 cycle, and the record clearly showed that this cycle was about to switch phases. That is to say, the current epoch—the ‘Holocene’, the 10,000 years of warm stable climatic upon which agriculture-based civilization had been built—was about to end.

Quaternary Geologists promote a cooling scare

The realization that we are at the end of a warm period was not itself alarming, as rapid climate change on a geological scale might be 1^o C per millennia. Such a gradual trend would hardly be recognizable with all the local and global fluctuations known to occur across centuries and decades. If the decline out of past warm periods were associated with wider fluctuations on these time scales then this would remain unknown because the proxies indicators for temperature did not have the necessary resolution to pick them up. However, soon some geologists were claiming resolution down to a century or two which revealed evidence of climatic instability as previous interglacial epochs ‘broke down’. According to the Danish geologist, Willi Dansgaard, if the deep past is anything to go by, then ‘the conditions for a catastrophic event are present today’. This quote comes from the conclusion of a paperpresented to a conference at Brown University early in 1972 that was called in light of the new evidence to answer a question of singular pertinence:

The present interglacial, how and when will it end?

After the conference, its 46 attending and non-attending participants agreed on a statement that included a warning about an imminent energy/food/climate crisis:

In man’s quest to utilize global resources, and to produce an adequate supply of food, global climatic change constitutes a first order environmental hazard which must be thoroughly understood well in advance of the first global indications of deteriorating climate.

Later in the year this statement was published in Science, and then the organizers of the conference Kukla and Matthews sent their letter to the White House.

Leverage the cooling scare for climate research funding: A United States Climate Program

During the 1960s, in the USA and internationally, atmospheric scientists had been lobbying for funding for coordinated climatic research. In the late 1960s the Global Atmospheric Research Program (GARP) was established to coordinate atmospheric research using new technologies especially satellites. While its mandate included climatic research, in fact the emphasis was placed much more on understanding and predicting weather, and so science administrators continued to lobby for a research program specifically targeting climate. One of these was the founding director of NOAA Robert White, who chaired the panel on ‘The Present Interglacial’ that was established ad hoc in response to the geologists’ letter to the president.

This panel’s report was released in 1974 as no less than a proposal for a National Climate Program. From this time we can see a general push for general geo-physical research (atmospheric and oceanic) leveraging the concerns abroad about the food/energy/climate future. By 1979 this push had achieve significant success after a National Climate Act passed late in 1978. Although the funding remained modest, important bureaucratic infrastructure was put in place, including a National Climate Program Office (under NOAA) and an inter-agency National Climate Program Policy Board. Not long after it was established, the prevailing concern at the Policy Board switched from cooling to warming. It was at this Board in 1986 that another fateful letter, this time from the Executive Director of the UN Environment Programme, would be addressed. Mustafa Tolba’s letter (to Secretary of State Schultz) was attached to the report of the 1985 Villach Carbon Dioxide Conference, which had achieved a ‘scientific consensus’ declaring that it was time to move towards developing a policy response to the warming threat. Following debate at this climate policy board (and elsewhere in the US government) it was eventually decided that a further assessment was required by an intergovernmental panel, that is, by what would be the Intergovernmental Panel on Climate Change (IPCC).

Leverage the cooling scare for climate research funding: A United Nations Climate Program

At the same time that steps were taken to implement their own national climatic program, the US also lobbied the United Nations and its World Meteorological Organization (WMO) for a world climate program. The formal origins of this lobbying can be found in a speech by Henry Kissinger to the UN General Assembly in April 1974.

In that speech, Kissinger called on the world community to come together to solve common problems. He specifically mentioned that science should be used to solve problems that science helped to create. To his list of examples he added one threat that was not cause by science but that was entirely ‘natural’. This was the threat of climatic changes and it had implications for global food and population policy. Through Kissinger’s speech the USA proposed that the WMO (and the ICSU) ‘urgently investigate this problem and offer guidelines for immediate international action’.

In the 1970s Robert White was also the head of the US delegation to the WMO. This meant that during 1974 not only was he coordinating efforts to get going a National Climate Program in the USA, but at the same time he was following up on Kissinger’s request at the WMO in Geneva.

When White formally approached the WMO with the US proposal, the WMO was all but ignoring the global cooling scare. However, in response to the USA request it acted quickly to establish an Expert Panel on Climatic Change. Thus began a series of events that led to the WMO headlining the climate issue. What follows is a brief outline.

From cool to warming at the WMO

In 1976 the WMO Expert Panel on Climatic Change released an ‘authoritative statement’ that downplayed concerns about a long-term trend towards cooling to instead emphasize short term fluctuations, including those that might be due to manmade effects. This panel then set about organizing the first World Climate Conference to launch the World Climate Program. At the 1979 World Climate Conference, much concern was raised about the carbon dioxide warming threat and the conference statement included an appeal to all nations that they ‘foresee and prevent’ manmade climate change. However, those in charge of the research component of the World Climate Program refused to address directly the carbon dioxide issue. The WMO Executive Council supported this position each time it was brought to their attention. The WMO’s reluctance to directly address the issue led Tolba at UN Environment Programme to take matters into his own hands. In 1983 he commissioned the first international study specifically addressing the issue (SCOPE 29). At its completion he called the famous meeting at Villach in 1985, where the climate treaty push began. The promotion of the ‘scientific consensus’ achieved at Villach, by Tolba and others, generated much discussion internationally. Importantly, it was taken seriously by the US Climate Policy Board and the US Department of State, where there was much debate about how to respond. When the matter was raised at the 1987 World Meteorological Congress, the US position was to call for another assessment of the problem by an intergovernmental panel. There was broad agreement with this view and so the IPCC was born.

Thus it can be seen that the cooling scare—linked as it was with the food and energy crisis—provided the impetus behind the launch of the warming scare, and it also provided the institutional platforms upon which the launch of that scare would take place.