A 19th-century scientist and suffragette was the first person to discover carbon dioxide could warm the Earth but her work was lost to history.

Eunice Foote devised a series of ingenious experiments that involved isolating the component gases that make up the atmosphere into glass cylinders and leaving them in sunlight. She discovered the cylinder filled with carbon dioxide trapped the most heat and “was many times as long in cooling”.

“An atmosphere of that gas would give to our Earth a high temperature,” she wrote in her 1856 paper Circumstances Affecting the Heat of the Sun’s Rays.


Foote’s paper was presented at the 1856 annual meeting of the American Association for the Advancement of Science (AAAS) by Professor Joseph Henry, who was founding director of The Smithsonian Institution. It is not clear why Foote did not present it herself – she did present a paper on a different topic at the event the following year.

Had it not been lost to history, her work would have formed the basis of modern climate science.

Three years later, the Irish scientist John Tyndall published his famous paper identifying the gases responsible for the greenhouse effect. He did not cite Foote’s earlier paper and, for more than 160 years, he has been credited with discovering the link between carbon dioxide and global warming.

“On the face of it, the significance of the paper passed everyone by who could have had a particular interest in it,” said scientist and historian Roland Jackson.

Some historians think Tyndall was simply unaware of Foote’s paper. Others say he must have been since it was published in the November 1856 issue of The American Journal of Science and Arts (page 382) and he had an article about colour blindness in the same issue (page 143) – although he would not be the first scholar to thumb straight to his own work.

Tyndall – with his rigorous training and state-of-the-art laboratory – conducted a more sophisticated experiment but Foote’s hypothesis that “long-term changes in atmospheric carbon dioxide levels could affect the temperature of the Earth was remarkably prescient,” said Katharine Hayhoe, a climate scientist at Texas Tech University. She "was the first person to say in print that if carbon dioxide levels were higher, the planet would be warmer".