The scientific understanding of how increased carbon dioxide in the atmosphere resulted in warmer temperatures is not a modern discovery. 163 years ago, Eunice Newton Foote documented the results of her experiment in a paper presented by Prof. John Henry of the Smithsonian Institution at the American Association for the Advancement of Science conference in 1856. Entitled, “Circumstances affecting the heat of the sun’s rays,” the paper was the first research linking increased carbon dioxide with warmer air. Foote demonstrated this by testing the rise in temperature in glass cylinders containing a either CO2, common air, or hydrogen. Noting that the cylinder containing CO2 had the highest temperature reading, Foote then theorized:
“An atmosphere of that gas would give to our earth a high temperature; and if, as some suppose, at one period of its history, the air had mixed with it a larger proportion than at present, an increased temperature from its own action, as well as from increased weight, must have necessarily resulted.”
Foote was the first scientist to identify the root cause of the greenhouse effect, tying and increase in carbon dioxide in the air to warmer global temperatures. For a long time, her contribution to this area of climate science went unacknowledged, with Irish scientist John Tyndall work produced three years later more commonly being cited as the earliest research linking CO2 emissions with global warming.
The two-page paper published by Foote is available in the public domain:
Foote, E. (1856). ART. XXXI.–Circumstances affecting the Heat of the Sun’s Rays. American Journal of Science and Arts (1820-1879), 22(66), 382.