Background Biases against crediting women scientists for their work led to a lack of documentation about her contributions and scientific achievements, and Foote fell into obscurity. Scientists and journalists generally agree that happened because she was a woman and an amateur scientist, and American scientists were then less respected than were Europeans. Her failure to name the specific works of the scientists that had influenced her marked Foote as an amateur. American researchers were recognized in her era for
natural history, but physics was still a developing field, and few American physicists had an international reputation. Tyndall became the person most often credited with the discovery of the greenhouse effect. Some writers credit the greenhouse effect to
Svante Arrhenius, the Swedish
Nobel laureate in chemistry, who used
physical chemistry to calculate how increases in the amount of atmospheric carbon dioxide can cause the Earth to warm and proved that human interaction with the environment was a direct cause of climate change. In 1902,
Susan B. Anthony made a speech calling on younger feminists to take up the reins from founders of the movement like "Elizabeth Cady Stanton,
Lucretia Mott, Eunice Newton Foote,
Mary Livermore, and
Isabella Beecher Hooker." Institutionalized neglect of women's history and distortion of the historical record by historians who did not analyze or include women's experiences led to little being known about early feminists. Before 1960 only thirteen texts published in the United States dealt with women's history. Of those, five focused on colonial women, and three focused on
Antebellum Southern women.
Women's liberation activists began making demands for the increased representation of women in academia in the late 1960s. They wanted research into women's history to be expanded and for groups such as
people of color and other marginalized communities to be part of the historic record. In 1969, those activists formed the
Coordinating Committee on Women in the Historical Profession as an affiliate of the
American Historical Association, hoping to address historical omissions and eliminate discrimination and recruiting problems in the profession of historians. The push for the inclusion of women as both historical subjects and a field of study for academics resulted in the first university
women's studies program being launched in the United States in 1970. The first texts specifically written about
first-wave feminists were written after 1975.
Recovery Women scholars began recovering Foote's role as a nineteenth-century scientist in the 1970s. In 1976, historian
Sally Gregory Kohlstedt noted Foote's participation as the only woman at the 1857 meeting of the AAAS in her history of that organization. Kohlstedt also noted both Elisha's membership in the AAAS from 1856 to 1860, and Eunice's presentation of papers as a non-member. Deborah Jean Warner mentioned Foote's articles, and her participation in the 1856 and 1857 AAAS conferences, in her article "Science Education for Women in Antebellum America" published in 1978 in the History of Science Society's international journal
Isis. Lois Barber Arnold, who taught in the Science Education Department of the
Teachers College, Columbia University, described Foote's experiments and participation in the AAAS conferences in detail in 1984, but noted that biographical data on her was lacking.
Elizabeth Wagner Reed, a
geneticist and scholar who studied biases against women in science, included a chapter "Eunice Newton Foote: 1819–1888" in her 1992 book
American Women in Science Before the Civil War. After the advent of the Internet and digitization, renewed interest in Foote was sparked by an article published by retired
petroleum geologist Ray Sorenson, in January 2011, in the
American Association of Petroleum Geologists' on-line journal
Search and Discovery.
Katharine Hayhoe, director of the Climate Science Center at
Texas Tech University, came across Foote's work when trying to answer a question by a colleague, Patricia Solís, about the lack of women in early climate research. She published an article "John v Eunice — A Fascinating Tale of Early Climate Science, Women's Rights and Accidental Poisoning" on Facebook in 2016. Leila McNeill, joint editor-in-chief of the magazine
Lady Science, published an article in the
Smithsonian magazine in December of that year, after discussing Foote with Sorenson. Around the same time, the physicist
John Perlin, who according to Nick Welsh, the executive editor of the
Santa Barbara Independent, is an author of two definitive histories on
solar energy, took note of Foote and began to research her history. By 2019, and because it was the 200th anniversary of Foote's birth, both academics and journalists from many parts of the globe had begun to regularly write about Foote and the
sexism and biases in the scientific community, which caused women, and particularly women scientists, to go unrecognized.
Evaluating Foote's experiments Roland Jackson, a
visiting scholar at the London-based
Royal Institution, set out in 2019 to analyze the questions of priority of Foote's work, as had Hayhoe in 2016. According to Jackson and Hayhoe, Foote's simple apparatus could not distinguish between the effects of
energy emitted from the sun and
infrared energy radiated by the Earth. Because Tyndall had more sophisticated equipment, Hayhoe noted that he was able to make these distinctions and conclusively measure the "heat-trapping properties" of several gases, by differentiating their infrared energy and the ability of molecules to absorb or emit radiation. Jackson acknowledged that it was possible that Foote did not "recognize, the distinction between solar radiation and radiated heat from the earth".
Ralph Lorenz evaluated Foote's work in a modern planetary climate context and noted that the
near-infrared (0.8 to 3
μm) radiation absorption reported by Foote is effectively an
antigreenhouse effect because it primarily involves solar radiation absorption rather than absorption and re-radiation of terrestrial longwave ('thermal') infrared radiation. An analysis of both of Foote's papers was published online in 2020 by
Joseph D. Ortiz, a geology professor at
Kent State University, and Jackson. Their printed findings in 2022 contain a description of Foote's methodology. They pointed out that although she did not cite specific works by other scientists, she referenced de Saussure,
Alexander von Humboldt, and
Edward Sabine. (Reed had previously noted that Foote had also referenced
Henri Becquerel,
Jean-Baptiste Biot, and
Joseph Louis Gay-Lussac.) They also noted that Foote "did not measure the natural greenhouse effect of the earth's atmosphere", but rather studied the heating of gases inside glass vessels. The walls of these vessels would have blocked longwave infrared radiation from either entering or leaving, while allowing some heat to escape via
conduction. Accordingly, her results did not directly indicate how the greenhouse effect operates in a natural atmosphere, but they did provide quantitative information about how gases, including greenhouse gases, absorb and radiate heat. Ortiz and Jackson's analysis traced the derivation of Foote's ideas and explored how she constructed, carried out, and interpreted her experiments. They found that she conducted her experiments using a control and a test vessel, which were made as similarly as possible. Her experimental design repeated pairing so that she could measure changes between full sun and shadow, vacuumed and condensed air, damp and dry air, and ambient atmosphere and for each vessel. Although she did not attempt to answer how or why heating occurred, her results confirmed the questions she sought to answer: "Does the concentration of gas in the atmosphere affect its warming response to the Sun's rays?; Does the composition of the gas in the atmosphere affect its warming response to the Sun's rays?; and Can the effect of different gases on the warming response of the Sun's rays be ranked?"
Analysis of Foote's pioneering role in climate science Reed's chapter gave biographical details on Eunice and her family and presented a detailed analysis of her scientific work. She recognized that Foote's experiments confirmed that when subjected to sunlight, carbon dioxide became warmer than air "thereby demonstrating what we call the greenhouse effect today". In 2010, when Sorenson came across a summary of Foote's work in an 1857 volume of
The Annual of Scientific Discovery, he was unaware that the full paper had been published. He also did not know how much of what publisher
David Ames Wells wrote in the summary was "attributable to [Foote]". Sorenson recognized that Foote's work had preceded Tyndall's in making the connection between carbon dioxide and climate change, but believed her lack of recognition for the discovery was that her work had merely been an oral presentation. He published an update to his initial findings on Foote in 2018, and reported "an examination of the
American Journal of Science and Arts (AJS) was conducted, and the original paper [by Foote] was found in the November 1856 issue" ... "The published AJS paper clearly shows that the idea of climate warming due to rising levels of atmospheric originated with Eunice Foote." Jackson's work in 2019 confirmed that Foote's experiments showing that water vapor and absorb heat occurred three years before Tyndall made a similar claim. He also validated that her observation that differences in atmospheric levels of water vapor and would result in climate change preceded Tyndall's claim by five years. Lorenz reported in 2019 in his work
Exploring Planetary Climate that Foote had made her discoveries proving that moist air produced more warming than dry air, and that variances in air density impacted warming, prior to Tyndall. Perlin concurred, describing Foote as "the
Rosa Parks of science, ... the first woman to have a paper read at a major scientific meeting ... first woman to have a paper published in the proceedings of a major scientific meeting ... [and] the only woman to be published in serious physics journals until
Madame Curie". Ortiz and Jackson concluded that Foote was the first to demonstrate absorption of heat by carbon dioxide and water vapor, but she did not isolate or detect the absorption and emission of
radiant energy within the thermal infrared range, which causes the greenhouse effect.
Debate on whether Tyndall knew of Foote's work The rediscovery of Foote also sparked academic debate on whether Tyndall knew of her work. Hayhoe's position in 2018 was that there was inadequate information to make a determination. Perlin strongly believed that Tyndall did know, because one of his papers was published in the 1856
American Journal of Science along with Foote's. Jackson, who also wrote a biography of Tyndall, believes that Tyndall probably never knew of Foote. He acknowledges the possibility that Tyndall could have known, as he was one of the editors of the
Philosophical Magazine and could have been involved in the selection of the articles it chose to publish. Jackson also notes that many European scientists, including
George Stokes and
William Thomson, were unaware of Foote's work since her name is not mentioned in any of the "correspondence, journals, or published papers of the critical physicists" of her era. Perlin countered Jackson's view because, in an earlier incident, Tyndall had not credited precedent work by Henry and Tyndall was known to have little regard for women's intellectual capacity. Jeff Hecht, a science and technology writer, acknowledged that the reasons why Tyndall did not credit Foote remain unknown but that he "…might have ignored a discovery claimed by a woman". Like Perlin, Hecht pointed out that Tyndall "…failed to credit discoveries by men like
Colladon, and quarreled over priority with some other prominent scientists of his time". Jackson rebutted that Tyndall had only limited interest in climate and after 1861, never published again on the subject as his interest was in studying the effect of radiation upon molecules. Jackson stated that it was scientists who gave Tyndall the title of "founder of climate science" and not a title that Tyndall had claimed for himself. ==Legacy and recognition==