The forgotten woman who discovered the greenhouse effect

From The Marginalian

On an anonymous desk in a spartan classroom of the pioneering Troy Female Seminary, a teenage girl with blue-grey eyes and an oceanic mind is bent over an astronomy book, preparing to revolutionize our understanding of the planet.

The year is 1836.

No university anywhere in the world would admit her.

No scientific society would grant her membership.

Still, Eunice Newton Foote (July 17, 1819–September 30, 1888) would go on to become the first scientist to link atmospheric carbon dioxide levels to rising planetary temperature.

One August day half a lifetime after graduating from Troy and throwing her energies at the suffrage movement — Susan B. Anthony would celebrate her as one of its founders — Eunice folded her hands into her lap in an auditorium full of distinguished scientists and their dressed up wives as she waited to watch someone else present her own work. A decade earlier, astronomer Maria Mitchell had become the first woman admitted into America’s scientific pantheon, the American Association for the Advancement of Science — but on the default certificate of admission, the word Fellow had been crossed out in pencil and Honorary Member handwritten over it. Women were still in the shadows of science. Like Beatrix Potter’s revelatory research into the reproduction of algae, Eunice Foote’s paper was read on her behalf by a man: the secretary of the Smithsonian Institution.

That paper — Circumstances Affecting the Heat of the Sun’s Rays, published in 1856 — would remain the only physics paper published by an American woman for three decades, until a year after Eunice’s death.

In it, she detailed her simple, ingenious experiments demonstrating the heat-absorbing properties of water vapor and carbon dioxide:

Using four thermometers, an air pump, and two glass cylinders — one filled with carbon dioxide (or “carbonic acid gas,” as it was then known) and the other with ordinary air — she found that when placed in direct sunlight, the CO2 cylinder trapped more heat and maintained it longer than the other.

She concluded that “an atmosphere of that gas would give to our earth a high temperature” and that if carbon dioxide levels in our current atmosphere were to rise, so would the planet’s temperature.

Here was the first human being to whisper the threat of global warming. And here was an era that silenced half its voices. The very man who presented her paper commented that while her experiments were “interesting and valuable,” they were of dubious significance. For more than a century, our cultural mythos would celebrate the Irish physicist John Tyndall — an ardent opponent of women’s suffrage — as the discoverer of what we now call the greenhouse effect. In 1859, he linked carbon dioxide and global warming in 1859. Three years earlier, he had contributed to the same issue of The American Journal of Arts and Sciences in which Eunice Foote’s paper was published; it was customary for publishers to send copies to all contributors.

Today, Eunice Foote is honored with an eponymous medal awarded by the American Geophysical Union for groundbreaking scientific research.

Complement her story with that of the polymathic Scottish mathematician Mary Somerville, for whom the word scientist was coined and these visionary maps of time, space, and thought by Emma Willard — America’s first female cartographer and information designer, founder of the Troy Female Seminary where Eunice Foote first fell under the spell of science — then leap forward a century with Rachel Carson and the birth of the modern environmental movement.