This is either an amazing coincidence or very strong evidence that the late 20th century global warming was just part of a natural climate cycle.
I downloaded the HadCRUT3 unadjusted global mean temperature data from Wood For Trees…
This temperature graph certainly indicates a significant secular warming trend from 1850-2010. Although it sure appears that the rate and magnitude of warming in the early 20th century was very similar to that of the late 20th century. So I plotted two time periods on the same chart: 1911-1944 and 1977-2010. Both series consist of monthly temperature anomalies, smoothed with a 13-month running average.
The similarity is amazing. The two time periods are statistically identical: Slope = 0.0013 R-squared = 0.76 to 0.78. A cross-plot of the temperature anomalies also yields an amazing correlation…
It appears that the only “anomaly” in the temperature anomaly trend occurred in the mid-20th century…
The mid-20th century cooling was far less pronounced than the late 19th century cooling… At least it was less pronounced according to HadCRUT3 and the other commonly used surface temperature series. Which is really odd. HadCRUT3 shows no cooling trend over the mid-20th century… But… The mid-century cooling trend was very real back in the 1970’s…
Global Cooling: 1954-1976
The ice age is coming, the sun’s zooming in
Engines stop running, the wheat is growing thin
A nuclear era, but I have no fear
’Cause London is drowning, and I live by the river
— The Clash
released in 1979
The first Earth Day was celebrated on April 22, 1970, amidst hysteria about the dangers of a new ice age. The media had been spreading warnings of a cooling period since the 1950s, but those alarms grew louder in the 1970s.
Three months before, on January 11, The Washington Post told readers to “get a good grip on your long johns, cold weather haters – the worst may be yet to come,” in an article titled “Colder Winters Held Dawn of New Ice Age.” The article quoted climatologist Reid Bryson, who said “there’s no relief in sight” about the cooling trend.
Journalists took the threat of another ice age seriously. Fortune magazine actually won a “Science Writing Award” from the American Institute of Physics for its own analysis of the danger. “As for the present cooling trend a number of leading climatologists have concluded that it is very bad news indeed,” Fortune announced in February 1974.
“It is the root cause of a lot of that unpleasant weather around the world and they warn that it carries the potential for human disasters of unprecedented magnitude,” the article continued.
That article also emphasized Bryson’s extreme doomsday predictions. “There is very important climatic change going on right now, and it’s not merely something of academic interest.”
Bryson warned, “It is something that, if it continues, will affect the whole human occupation of the earth – like a billion people starving. The effects are already showing up in a rather drastic way.” However, the world population increased by 2.5 billion since that warning.
Fortune had been emphasizing the cooling trend for 20 years. In 1954, it picked up on the idea of a frozen earth and ran an article titled “Climate – the Heat May Be Off.”
The story debunked the notion that “despite all you may have read, heard, or imagined, it’s been growing cooler – not warmer – since the Thirties.”
The claims of global catastrophe were remarkably similar to what the media deliver now about global warming.
“The cooling has already killed hundreds of thousands of people in poor nations,” wrote Lowell Ponte in his 1976 book “The Cooling.”
If the proper measures weren’t taken, he cautioned, then the cooling would lead to “world famine, world chaos, and probably world war, and this could all come by the year 2000.”
There were more warnings. The Nov. 15, 1969, “Science News” quoted meteorologist Dr. J. Murray Mitchell Jr. about global cooling worries. “How long the current cooling trend continues is one of the most important problems of our civilization,” he said.
If the cooling continued for 200 to 300 years, the earth could be plunged into an ice age, Mitchell continued.
Six years later, the periodical reported “the cooling since 1940 has been large enough and consistent enough that it will not soon be reversed.”
A city in a snow globe illustrated that March 1, 1975, article, while the cover showed an ice age obliterating an unfortunate city.
In 1975, cooling went from “one of the most important problems” to a first-place tie for “death and misery.” “The threat of a new ice age must now stand alongside nuclear war as a likely source of wholesale death and misery for mankind,” said Nigel Calder, a former editor of “New Scientist.”
He claimed it was not his disposition to be a “doomsday man.” His analysis came from “the facts [that] have emerged” about past ice ages, according to the July/August International Wildlife Magazine.
The idea of a worldwide deep freeze snowballed.
Naturally, science fiction authors embraced the topic. Writer John Christopher delivered a book on the coming ice age in 1962 called “The World in Winter.”
In Christopher’s novel, England and other “rich countries of the north” broke down under the icy onslaught.
“The machines stopped, the land was dead and the people went south,” he explained.
James Follett took a slightly different tack. His book “Ice” was about “a rogue Antarctic iceberg” that “becomes a major world menace.” Follett in his book conceived “the teeth chattering possibility of how Nature can punish those who foolishly believe they have mastered her.”
Energy and Climate: Studies in Geophysics was a 1977 National Academies publication. It featured the following temperature chart, which clearly shows a mid-20th century cooling trend…
The current instrumental temperature data show no mid-20th century cooling trend… The late 1970’s instrumental temperature data clearly showed a mid-20th century cooling trend. The mid-20th century trend depicted in Budyko (1969) looks a lot like the HadCRUT3 cooling trend from 1878-1911…
If I substitute the 1878-1911 cooling trend for the 1944-1977 flat trend, HadCRUT3 would have very little in the way of a secular trend…
Why did the mid-20th century cooling vanish sometime between 1977 and 2010?