Sixty six years ago, on this day, July 1st, 1959, Canadian physicist Gilbert Plass has an article in Scientific American about … carbon dioxide build-up.
During the past century a new geological force has begun to exert its effect upon the carbon dioxide equilibrium of the earth]. By burning fossil fuels man dumps approximately six billion tons of carbon dioxide into the atmosphere each year [as of 2025 it’s about 40 billion tons]. His agricultural activities release two billion tons more. Grain fields and pastures store much smaller quantities of carbon dioxide than the forests they replace, and the cultivation of the soil permits the vast quantities of carbon dioxide produced by bacteria to escape into the air.
And
We shall be able to test the carbon dioxide theory against other theories of climatic change quite conclusively during the next half-century. Since we now can measure the sun’s energy output independent of the distorting influence of the atmosphere, we shall see whether the earth’s temperature trend correlates with measured fluctuations in solar radiation. If volcanic dust is the more important factor, then we may observe the earth’s temperature following fluctuations in the number of large volcanic eruptions. But if carbon dioxide is the most important factor, long-term temperature records will rise continuously as long as man consumes the earth’s reserves of fossil fuels.
The amount of carbon dioxide in the air was 315ppm. As of 2025, when this post was published, it is 430ppm. This matters because the more carbon dioxide in the air, the more heat gets trapped. The more heat, the more extreme weather events. You can make it more complicated than that if you want, but really, it’s not. Fwiw, I have a tattoo of the Keeling Curve on my left forearm.
The broader context was that the idea that carbon dioxide build-up would heat the earth can be dated back to the 1890s (it’s slightly more complex than that, but this will do for now), from work by Svante Arrhenius, the Swedish scientist who later won a Nobel Prize (for other work).
But Arrhenius’ proposal had been shot down, thanks to arrogance about knowing how carbon dioxide operates in the stratosphere, and Guy Callendar’s 1938 lecture to the Royal Meteorological Society hadn’t changed that.
The specific context was that Plass had been banging on about carbon dioxide build-up since May 1953, and had had various articles published in specialist journals and also in more “Popular” ones like American Scientist and Scientific American.
What I think we can learn from this is that UK elites will have been well-informed. Scientific American was advertised and sold in the UK…
What happened next – Plass was present at a couple more meetings – e.g. New York in January 1961 and again in March 1963, but wasn’t particularly “into” climate – it wasn’t his thing.
And the carbon dioxide kept accumulating, obvs.
