Definitive Evidence for Global Cooling Consensus in the 1970s (1)

A series of blogs analizing Thomas C. Peterson, William M. Connolley, and John Fleck’s (PCF) largely mistitled “The Myth of the 1970s Global Cooling Scientific Consensus” (Bulletin of the American Meteorological Society Volume 89, Issue 9, September 2008, pp 1325-1337). Previous considerations about a global cooling consensus in the 1960’s can be read here and here.


In an act of supreme irony, incontrovertible evidence for a “global cooling scientific consensus in the 1970s” is spelled out loud and clear in Thomas C. Peterson, William M. Connolley, and John Fleck’s (PCF) The Myth of the 1970s Global Cooling Scientific Consensus.

How did they manage then to show “global cooling scientific consensus in the 1970s” to be a “myth”?

By carefully adopting their own particular definitions for common words; by using the very “selective misreading of the texts” they accuse others to be guilty of (page 1326); and by using quite uneven criteria, strict regarding “cooling” and “consensus”, and loose on the “warming” side.

In the process, they have ended up discarding or having to liberally interpret most of the available literature. Furthermore, for an article dealing with a particular time period, PCF’s comments do appear temporally jumbled up. And they have created their own myths: the isolation of different types of climate research before the 1970’s, and the sudden appearance of CO2 as a factor affecting climate.



What is “global cooling”? At least at the beginning, PCF take it as synonym of “imminent ice age”:

PCF: “There was no scientific consensus in the 1970s that the Earth was headed into an imminent ice age. Indeed, the possibility of anthropogenic warming dominated the peer-reviewed literature even then.

Isn’t that a tad too catastrophist, too “2008”, to say the least?

Couldn’t there have been people in the 1970s convinced of, and worried about global cooling, without necessarily expecting “an imminent ice age”? It’s like trying to look at the past with our thoughts firmly anchored to the present, catastrophiliac era.

And what is a “scientific consensus”? Here’s PCF’s definition:

PCF: “[A global cooling scientific consensus] would be easily shown by both the presence of many articles describing global cooling projections and the absence of articles projecting global warming

So they would be satisfied of a “global cooling scientific consensus” only by “the absence of [scientific] articles projecting global warming”.

But that is an almost impossible feat. Even now in 2008, still there are peer-reviewed articles that do not agree with what is incessantly referred to as the “global warming consensus”.

A more open-minded approach would be to define as “scientific consensus” what most people would consider a “consensus”: having a large majority of scientists thinking global cooling was underway (just as a large majority of scientists think global warming is underway right now).

And that is exactly what PCF describe (referring to the 1972/1974 period):

PCF: “Meanwhile, newly created global temperature series showed cooling since the 1940s.[…] By the early 1970s, when Mitchell updated his work (Mitchell 1972), the notion of a global cooling trend was widely accepted, albeit poorly understood

“Widely accepted”: check. “Global cooling”: check.

So according to PCF, a lowering of global temperatures was indeed the mainstream view in 1972. And up to sometimes in the 1970s at least, the available scientific evidence pointed towards global cooling being a reality.

On the basis of what PCF have written, a “global cooling scientific consensus” did exist in the 1970s, if only for a few years.



One could still wonder, if there was indeed a “global cooling scientific consensus” in the 1970s, why didn’t PCF find more articles supporting it? That’s the subject of next blog in the series.