Guy Stewart Callendar, pictured in 1934

University of East Anglia ArchiveGuy Stewart Callendar, who predicted climate change in 1938.

Carbon dioxide emissions have been altering the climate since the Industrial Revolution, some 200 years ago, though it took us a while to figure that out. NASA scientist James Hansen first warned Congress about the dangers of greenhouse gases in 1988.

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But an earlier climate warning came five decades previous, way back in 1938. That’s when Guy Stewart Callendar, an engineer specializing in steam and power generation, published a paper that theorized that carbon dioxide emissions from industrial activity could have a greenhouse effect. His prescient paper appeared in the quarterly journal of the Royal Meteorological Society.

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Some scientists this month are commemorating Callendar’s little-noticed discovery. From the BBC:

Prof Phil Jones, from the University of East Anglia in Norwich, … said the steam engineer’s work was “groundbreaking”.

Callendar, born in Montreal, Canada in 1898, made all his calculations by hand in his spare time, decades before the effects of global warming became widely debated.

The son of English physicist Hugh Longbourne Callendar, who studied thermodynamics, Callendar worked from his home in West Sussex. …

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“He collected world temperature measurements and suggested that this warming was related to carbon dioxide emissions.”

This became known for a time as the “Callendar Effect”.

Memo to congressional Republicans: It’s the Callendar Effect, stupids, and we’ve known about it since before you were born. Well, before some of you were born.