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Global Warming Science And The Wars: Guy Callendar

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Guy Callendar, 1934.

Image courtesy Wikipedia.

Image courtesy Wikipedia.

Nearly everybody likes to be right, and scientists perhaps more so than the rest of us. Their professional lives, after all, are dedicated to uncovering the truth, which they do in part by quantifying and minimizing error. The interesting thing, though, is that in science there is more than one way to be right.

Consider the case of Guy Stewart Callendar. He should be famous. Scholar James Fleming writes flatly that “Callendar established the CO2 theory of climate change in its recognizably modern form.” It was Callendar who first used meteorological data to construct a global temperature time series; who first established the background concentration level of atmospheric CO2 and identified an anthropogenic increase; and who was instrumental in bringing thirty years of advances in spectroscopy to bear on climate studies. All of these types of studies are crucial to the modern understanding of CO2 and climate.

So why is Callender not better known today? Partly because he worked, not as an academic, but as a defense researcher. He not only lacked the “bully pulpit” of a professorial chair, but was expected to maintain discreet silence about his job-related research. Perhaps worse, he was—in terms of employment, though not of technical skill—an “amateur.” (In the auctorial heading of his 1938 paper on CO2-induced warming he is “G.S. Callendar, steam technologist.”) And partly it is because he did not anticipate the temperature declines experienced in the 1950s and 1960s. Thus, at the end of his life, he was wrong about the most central of his conclusions: that he had actually detected the human fingerprint on Earth’s climate.



One of the first surprises about Callendar is that this quintessentially English man was born, not in London or some leafy corner of Sussex, but in Montreal. His father, Hugh Longbourne Callendar, had since 1893 held a chair in Physics at McGill University. Among his many accomplishments there, he had in 1896 created the first Canadian x-ray images, and had helped to pioneer their use in clinical medical diagnosis. But after Guy Callendar’s birth on February 9, 1898, Professor Callendar accepted the Quain Chair of Physics, University College, London. He would be succeeded at McGill by no less than Ernest Rutherford, who wrote:

Callendar here was considered a universal genius and I gain a sort of reflected glory by carrying on with things Callendar alone was able to do. The trouble is that Callendar left such a reputation behind him that I have to keep rather in the background at present.

Redpath Museum, McGill University.  Image courtesy Gene Arboit & Wikimedia Commons.

Redpath Museum, McGill University. Image courtesy Gene Arboit & Wikimedia Commons.

James McGill Statue, McGill University.  Image courtesy Gene Arboit & Wikimedia Commons.

James McGill Statue, McGill University. Image courtesy Gene Arboit & Wikimedia Commons.

McGill University at play in 1884.

McGill University at play in 1884.

The elder Callendar’s career advanced again with a move to the Royal College of Science (later part of Imperial College) in 1902, and in 1905 the Callendar family—now including a fourth child, with Guy’s younger brother Max—was able to move into a fine home in the London suburb of Ealing. 49 Grange Road had 22 rooms, and—in addition to the greenhouse, tennis lawn, and putting green—boasted two garages equipped with “pit, crane, lathe and all tools” necessary to maintain the family car. The household was supported by a staff of four to six servants, plus a chauffeur and a gardener.