Modern climate change: Missing a woman, missing out on a discipline

Science has no national boundaries and no gender distinction. The world of women is not only beautiful and practical, but also contains truth.

Science was of no country and of no sex. The sphere of woman embraces not only the beautiful and the useful, but the true.

Written by | Veronica

Raymond P. Sorenson, a retired American petroleum geologist, is obsessed with technical books before the American Civil War. One day in 2010, while flipping through the 1857 Annual of Scientific Discovery, a paper caught his attention. As early as 1856, the author had foresightedly linked the heat-absorbing ability of carbon dioxide to climate change. Three years later, Irish physicist John Tyndall (1820-1893) discovered that different gases absorb different amounts of heat under longwave infrared radiation, which was considered to confirm the connection between the carbon dioxide content in the atmosphere and what later generations called the greenhouse effect.

While Tyndall is regarded as a pioneer of modern climate science, the unknown author of the paper, Eunice Newton Foote (1819-1888), has been lost in the dust of history.

Sorensen soon realized that his accidental discovery would rewrite the history of a discipline. In January 2011, Sorensen published an article[1] describing his discovery, confirming Foote’s academic priority on the issue of carbon dioxide and climate change.

At this point, Eunice Foote and her groundbreaking research, which had been silent for more than a century, finally surfaced.

Figure 1. Annals of Scientific Discovery is a series of books compiled by American economist David Ames Wells (1828-1898), which includes many important scientific research documents and covers a wide range of fields. Eunice's paper was included in the 1857 volume. | Source: Biodiversity Heritage Library

Pioneers, like shooting stars, passed by in the early morning of August 23, 1856. Hundreds of important researchers in the American scientific community gathered in Albany, New York, to attend the 8th annual meeting of the American Association for the Advancement of Science (AAAS) to exchange their research results and research interests.

At the conference, Joseph Henry (1797-1878), a highly respected physicist at the time, presented a scientific paper written by a woman. This physicist, who left his name with the unit of inductance "Henry (H)", is considered one of the greatest American scientists after Benjamin Franklin (1706-1790).

Before reading his paper, Henry added an opening statement: "Science was of no country and of no sex. The sphere of woman embraces not only the beautiful and the useful, but the true."[2] This statement only survives in the handwritten notes of the conference stenographer and was later restored.

Figure 2. In the short film Eunice released in 2018, Eunice (right) sat in the audience and watched Henry read out her research on the stage. | Source: Youtube

This was the first time that Eunice's paper was publicly presented. Titled "Circumstances affecting the heat of the sun's rays"[3], it was only two pages long and concise. Without any professional experimental equipment, Eunice only used an air pump that was "quite effective", four mercury thermometers, and two glass cylinders with a diameter of about 10 cm and a length of about 76 cm to build her scientific world.

Eunice used an air pump to extract the gas from one glass cylinder and then pumped it into another glass cylinder, making the gas in one cylinder thinner and the gas in the other cylinder denser. A thermometer was placed in each of the two cylinders. After the two glass cylinders were placed in a cool place and reached the same temperature, they were moved to the sun and the temperature was observed every 2 to 3 minutes. Eunice repeated this temperature measurement process using dry air dehydrated with calcium chloride (CaCl2), saturated humid air, ordinary air, hydrogen (H2), oxygen (O2) and carbon dioxide (CO2).

From the observed data, Eunice came to three conclusions:

① As the density increases, the gas's ability to absorb the sun's heat increases, and vice versa;

② Compared with dry air, moist air has a stronger ability to absorb the heat from the sun

③ Gases containing carbon dioxide heat up most significantly under sunlight, and take the longest time to cool down after being moved to a cool place.

Figure 4. The data recorded in Eunice's 1856 paper is presented in a modern chart. The composer performed a logarithmic fit on the gas heating process recorded by Eunice, and used the difference (in degrees Celsius) between the temperature values ​​at the 4th, 5th and 6th time points of the gas heating fitting function and the temperature values ​​at the corresponding time points of the ordinary air heating fitting function as the vertical axis to calculate this figure. | Source: The Royal Society Notes and Records[4]

Eunice's experimental design was ingenious and her conclusions were solid, but more importantly, in the mid-19th century when the public had not yet begun to pay attention to the issue of climate change, Eunice had the advanced awareness to link the heat-absorbing characteristics of carbon dioxide she observed with global climate change. At the end of her paper, she inferred that if the proportion of carbon dioxide in the earth's atmosphere increased during a certain period, the global temperature would also rise. (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.)

However, this paper was not included in the AAAS annual proceedings, which is how all papers presented at the annual meeting should be included. Its full version was published in the American Journal of Science and Arts in 1856, under the name “Eunice Foote” (Figure 3). Subsequently, many magazines, including Scientific American [5] (1856) and the New York Daily Tribune [6] (1856), published abstracts of Eunice’s research. The only two European abstracts omitted her direct conclusions about the impact of carbon dioxide on the climate, and the abstract in the Edinburgh New Philosophical Magazine even only marked the author as Mrs. Elisha Foote (Eunice’s husband).

Even Henry, who was most likely to help her, did not fully appreciate the significance of the article due to the limitations of his research field (mainly electromagnetism). Henry acknowledged that Eunice’s research was valuable, but at the time he believed that “it was very difficult to deeply analyze the significance of these experimental results.” (Although the experiments were interesting and valuable, there were many difficulties encompassing any attempt to interpret their significance. By Joseph Henry) [7]

Figure 3. Eunice's paper "Environmental conditions affecting the thermal energy of solar rays". | Source:
https://archive.org/details/mobot31753002152491/page/381/mode/2up?view=theater

Eunice Foote’s research was like a shooting star, which disappeared from people’s sight after a moment of brilliance. Fortunately, she published a complete paper, making it possible for future generations to trace and explore her research. With “pure luck,” Sorensen finally brought this legendary woman back into the public eye and into the history of science[8].

The father of modern climate science in the eyes of later generations

When we look back at the scientific history of the greenhouse effect, Irish physicist John Tyndall is a key figure that cannot be avoided.

Unlike Eunice, who was an amateur science enthusiast, Tyndall, who obtained his doctorate from the University of Marburg in Germany, had close contacts with the most outstanding experimental physicists of the time and used extremely sophisticated experimental instruments. His most famous contribution was the discovery in 1869 that light would be scattered by dispersed particles when passing through colloids, which he named the "Tyndall effect."

By the 1850s, Tyndall had become famous for his work on diamagnetism[9] and the structure and motion of glaciers[10]. After reading Macedonio Melloni's work on thermal radiation[11], Tyndall decided to test the absorption of radiation by gases instead of liquids and solids. He firmly believed that matter was made up of molecules and atoms, and that the chemical composition (molecular structure) of matter would also affect the radiation-absorption process.

Tyndall first measured the temperature rise of “simple gases” (now known as single gases) such as hydrogen, oxygen and nitrogen under long-wave infrared radiation, but the results were not ideal. Only when he measured more complex gas molecules such as water vapor, carbon dioxide and methane did he observe a significant temperature rise. Tyndall realized that the results of this experiment were of great significance, and quickly reported his research in the form of an outline to the Royal Society of London that year (1859), and formally published the paper in the Proceedings of the Royal Society in 1861 [12]. This discovery became the theoretical basis of the greenhouse effect, and Tyndall himself was later hailed as the “father of modern climate science”.

Figure 5. Schematic diagram of Tyndall's thermal radiation experimental device. | Source: Royal Institution of the Great Britain

There are two main differences between Tyndall’s and Eunice’s experimental designs[13]: First, Eunice used full-spectrum solar radiation to heat the gas, while Tyndall’s heating source was a Leslie cube filled with boiling water, which produces long-wave infrared radiation. Second, Tyndall used a differential spectrometer of his own invention, which could sensitively and accurately measure differences in heat absorption, while Eunice’s experimental device was relatively simple and primitive. But it is worth noting that, unlike Eunice, Tyndall himself had no interest in climate change, and in his 1859 paper he never mentioned the possible impact of his discovery on global climate change.

Figure 6. Physicist John Leslie invented the Leslie cube (left) in 1804. The cube has four perpendicular surfaces, three of which are plated with a layer of gold, silver and copper, and the other is covered with a varnish of isinglass. When the cube is filled with boiling water, the temperature detector (right) detects significantly stronger heat emission from the muscovite surface than from the other three surfaces. | Image source: Wikipedia

Did Tyndall know about Eunice's research before the experiment? This has become a historical mystery. There are many controversies related to this, and the truth is unknown. Some scholars question that Tyndall's paper on color blindness research was published in the same journal as Eunice's research, so he is very likely to have read her paper [8]. Tyndall's biographer Roland Jackson said that Tyndall himself may have sexism and believed that female scientists did not have the same imagination and exploration ability as men. But at the same time, Jackson also believed that with Tyndall's personality and character, it would be impossible for him to commit academic misconduct; not to mention that in the mid-19th century, international exchanges were scarce, and intercontinental exchanges were even scarcer. If academic achievements wanted to spread to the other side of the ocean, they could only rely on personal social relationships [13]. For female amateur science enthusiasts like Eunice who had limited connections, this seemed impossible.

Eunice was unique, precious, and a flower that could have blossomed even more brilliantly. As the September issue of Scientific American commented, Eunice’s research “fully demonstrated that women have the creativity and rigor to study any subject.”[14]

The columns of the Scientific American have often times graced with articles on scientific subjects, by ladies, which would do honor to men of the highest scientific reputation; and the experiments of Mrs. Foot afford abundant evidence of the ability of woman to investigate any subject with originality and precision.

It is particularly regrettable that Eunice was unable to continue her research and further expand her thinking on climate change. The sparks of thought that women contributed to the opening of modern climate science were extinguished because of the environment's contempt and indifference to women and the unfavorable conditions for women's scientific research. Today, while reflecting on the unfair treatment that female researchers have suffered, how to provide support and help to the female researchers around us may be a more worthy question to think about. After all, the past cannot be changed, but the future is still full of possibilities.

What kind of soil gave birth to the "flower of greenhouse effect"? In the early 19th century, Western women began to have the opportunity to receive higher education, which was previously monopolized by men. However, it was not until the end of the 19th century that women's higher education was developed on a large scale (see "Coeducation, a century of struggle | Where have the women scientists gone?"). Throughout the 19th century, only 3,400 papers were written by female scientific researchers, less than 1% of the total number of papers published. Among these 3,400 papers, 1,400 were written by American female scientists, most of which were in the fields of botany, zoology and other life sciences, and only 16 papers were in the field of physics. Among these 16 papers, only two were published before 1889, both of which were written by Eunice Foote[15].

What kind of growing environment created such a shining woman?

The story begins on a farm in Connecticut, USA. Born in 1819, Eunice's original name was Eunice Newton. Her father was a distant relative of the famous Isaac Newton (1643-1727). But without this halo, they were just an ordinary farmer's family.

At the age of 17, Eunice entered Troy Female Seminary, New York. This college was called "Mecca for women" (Mecca is Mecca, the holy place in Islam). It was founded by feminist Emma Willard in 1824 and was the first preparatory school for girls in the United States. Troy Female Seminary shared teaching facilities with the neighboring Rensselaer Polytechnic Institute and had the only two chemical laboratories in the world designed for teaching at that time. It was here that Eunice mastered experimental skills and learned how to conceive and execute experimental topics.

It is worth mentioning Amos Eaton (1776-1842), the founder of Rensselaer Polytechnic Institute. Eaton was a lawyer, but he loved nature since he was a child. While practicing law, he also engaged in botanical research. He was sentenced to life imprisonment for participating in land speculation and suspected fraud, but fortunately he was pardoned in the fifth year of his sentence. After being released from prison, he continued to study botany, geology, and chemistry, compiled a botanical dictionary, gave lectures, and co-founded a school... He became a legendary figure who promoted modern teaching reforms[16]. He believed that men and women should have equal rights to receive scientific research education, and for this purpose he carefully guided a teacher at the Troy Women's Seminary. The teacher designed a complete set of all-encompassing scientific research courses for female students, and Eunice was one of the beneficiaries.

Figure 7. Wesleyan Chapel in Seneca Falls. The first women's rights convention in the United States was held here from July 19 to 20, 1848. | Source: Getty images

In addition, one of Eunice’s neighbors also had a profound influence on her—she was the famous Elizabeth Cady Stanton (1815-1902), one of the pioneers of the American feminist movement. In 1848, the first women’s rights conference led by Stanton was held in Seneca Falls, New York, and Eunice was one of the participants. The conference adopted the Declaration of Sentiments, calling for women to enjoy equal rights with men in higher education, work environment, and marriage life. Eunice, who was deeply touched, also participated in the publication of the conference minutes [17].

Figure 8. The signature page of the Declaration of Sentiments. Eunice Foote's name is in the first column, line 5, and her husband Elisha Foote's name is in the men's section in the first column, line 4. | Source: Library of Congress, National American Woman Suffrage Association Collection

When people look back at the Declaration of Sentiments, they find that in addition to Eunice herself, her husband Elisha Foote also signed it. Elisha was a judge, inventor, and mathematician, as well as a supporter of the women's rights movement. He was one of the few male participants who eventually signed the Declaration of Sentiments. As a husband, Elisha became one of the most important supporters of Eunice's subsequent scientific research. He regarded her as an equal individual and encouraged Eunice to do the scientific research she loved; he introduced Joseph Henry to her, and as a member of AAAS, he secured an opportunity for his wife's research to be presented at the conference [8]. It can be imagined how much strength Elisha's firm support brought to Eunice.

Figure 9. Photo of Eunice's husband Elisha Foote. Eunice herself did not leave any public images. From the written records, we know that she was petite, with an oval face, dark brown hair and gray-blue eyes. | Source: Wikipedia

Liz Foote, a doctoral student in environmental science and behavioral science, is a distant relative of Elisha Foote. At the AAAS meeting in 2018, Liz learned about Eunice by chance and participated in a research project on Eunice. Liz said:

"But as a woman in the 1800s her professional options were nevertheless limited. To accomplish what she did, despite the realities of her time, is very impressive and should inspire anyone."[18]

Would the world be different today if…?

In 1856, Eunice's research on the absorption of sunlight by different gases received little response, and her predictions about climate change were ignored. The following year, Eunice published a paper on the relationship between atmospheric pressure fluctuations and changes in electric charge.[19] According to the Royal Society's Catalogue of Scientific Papers (1800-1900), this was the last physics paper published by Eunice.

If the scientific community had taken this research seriously, and had received sufficient resources and encouragement from others, Eunice might have thought of using long-wave infrared radiation instead of simple and primitive sunlight heating. With the help of advanced instruments and standardized laboratories, Eunice's next experiment should be more scientifically and delicately designed, and the quantitative results more accurate, and her conjecture about climate change might be further confirmed.

When the United States missed out on Eunice, it also missed out on the opportunity to take the lead in developing modern climate science. In the late 1860s, the Second Industrial Revolution began, ushering in the “electrical age”. At that time, the United States was booming with various scientific and technological inventions, accelerating its catch-up with the old capitalist countries represented by Britain. However, compared with applied research, basic research was relatively neglected. In the mid-19th century when Eunice lived, the development of the American physics community was far behind that of Europe. Even in the 1870s, there were less than 75 people who called themselves “physicists” in the United States, and before that, only Benjamin Franklin and Joseph Henry were famous abroad[20]. As Americans opened up and explored their land, natural history research flourished, but natural science research struggled.

If Eunice's research had been taken seriously in the United States and Europe, it might have become an opportunity for the development of climate science in the United States. Just like Liu Xiang's influence on Chinese track and field, the best athletes always attract the attention of the nation to this field, and this attention will bring policy support and resource tilt. The 1850s are generally regarded by modern climate change researchers as the starting point of industrialization. In other words, human activities at this time had not yet had an impact on climate change. However, the growth of tree rings shows that in the 1860s, the temperature in the Northern Hemisphere rose significantly [17] (due to the large-scale burning of fossil fuels and deforestation). If the United States had seized the opportunity of the development of climate science at that time, humans might have been able to respond quickly to the climate change during this period.

Humanity’s understanding of the greenhouse effect began in 1827 when mathematician Joseph Fourier (1768-1830) proposed the idea that the Earth’s atmosphere has a heat-insulating effect. Fourier believed that if the atmosphere could not retain heat, the temperature of the Earth’s surface would be much lower than the actual value based on the volume of the Earth and the distance between the Earth and the Sun.[21] The research of Eunice and Tyndall specifically answered the question of “which atmospheric components cause this heat-insulating effect”. It should be noted that what they discovered was the absorption of thermal radiation by a small group of basically isothermal gas, which is not the same as the radiation-heating of the entire atmosphere as we know it today. To extend the results of this ideal experiment to the entire atmosphere, a lot of theoretical knowledge developed later is needed.

Specifically, with the development of electromagnetism, scientists gradually formed a basic understanding of radiation and established the theory of atmospheric radiation transmission. Physicists were able to extend simple radiation heating in a small range to the real atmosphere with a very complex temperature stratification. Only then was it confirmed that "the increase in atmospheric carbon dioxide concentration can lead to an increase in near-surface temperature." In the early 1960s, the measurement results of American meteorologist Charles David Keeling (1928-2005) showed that the atmospheric carbon dioxide concentration was rising rapidly [22]. When the conclusion that "the increase in atmospheric carbon dioxide concentration can lead to an increase in near-surface temperature" was linked to the facts of "the rapid increase in atmospheric carbon dioxide concentration" and "global warming", the greenhouse effect truly became a meaningful scientific issue. And Eunice's research was the starting point of the greenhouse effect argument chain. If humans could have predicted a few years earlier that human activities would affect the climate, perhaps the ecological environment of the earth today would have had more breathing space.

What is even more regrettable is that Eunice’s silence is only part of a larger narrative of women being deprived of equal rights in scientific research institutions. In 2018, the University of California, Santa Barbara held a seminar with the theme of “Science Knows No Gender” to commemorate Eunice Foote’s outstanding contributions.[23] Leila Carvalho, a professor of meteorology at the university, said: “I can’t help but wonder, how many more ‘Eunice Foote’ are there waiting for us to discover? How many scientific achievements have been buried in history because of social pressures caused by gender, ethnicity or race?”

Figure 10. In the short film Eunice released in 2018, Eunice, played by British actress Helen Jessica Liggat, wears a complicated Victorian dress and conducts experiments under simple conditions. | Source: Youtube

If women are shut out, science will lose half of its power. Eunice proved that women have the same potential as men in the field of scientific research, which is an inspiration to countless female researchers. Today, they are no longer restricted by the identity of "amateur science enthusiasts", and can get rid of complicated skirts and enter the hall of science in simple clothes. In Eunice's time, the concentration of carbon dioxide in the atmosphere was only 290ppm (parts per million). She may not have expected that in just over a century, this value would exceed 410ppm[24]. As stated in the 2019 Women's Connected Leadership Declaration on Climate Justice, in today's increasingly serious global warming and climate change crises, "To change everything, we need everyone."[25]

Figure 11. The Women’s Joint Leadership Declaration on Climate Justice is committed to supporting women around the world to speak out, take action and strive for leadership in the field of climate protection. | Source: womenleadclimate.org

Acknowledgements

I would like to express my sincere gratitude to Shi Wen, a graduate student in the Department of Earth System Science at Tsinghua University, for providing reference opinions on the professional knowledge involved in this article.

References

[1] Sorenson, RP (2011). Eunice Foote's pioneering research on CO2 and climate warming. Search and Discovery.

[2] https://publicdomainreview.org/collection/first-paper-to-link-co2-and-global-warming-by-eunice-foote-1856.

[3] Foote, Eunice (1856). Circumstances affecting the heat of the sun's rays. American Journal of Science and Arts, p.382-383.

[4] Ortiz, JD, & Jackson, R. (2020). Understanding Eunice Foote's 1856 experiments: heat absorption by atmospheric gases. Royal Society Notes and Records. doi: 10.1098/rsnr.2020.0031.

[5] 'Scientific ladies: experiments with condensed gases', Sci. Amer.12, 5 (13 September 1856).

[6] 'Section of physics and mathematics', New York Daily Trib., 26 August 1856, p. 7.

[7] Section of physics and mathematics, New York Daily Tribune, 26 August 1856, p.7.

[8] Mandel, Kyla (2018). This woman fundamentally changed climate science—and you've probably never heard of her. ThinkProgress. Center for American Progress Action Fund.

[9] Jackson, Roland (2015). John Tyndall and the early history of diamagnetism. Ann. Sci.72, 435–489.

[10] Jackson, Roland (2018). The ascent of John Tyndall. Oxford University Press, pp. 113–151, and 324–326.

[11] Melloni, Macedonio (1850). La Thermochrose, ou la Coloration Calorifique. Naples.

[12] Tyndall, John (1861). Note on the transmission of radiant heat through gaseous bodies. Proceedings of the Royal Society of London, 10, 37-39.

[13] Jackson, Roland (2019). Eunice Foote, John Tyndall and a question of priority. Royal Society Notes and Records. doi: 10.1098/rsnr.2018.0066.

[14] Scientific Ladies.—Experiments with Condensed Gases. (1856). Scientific American, 12(1), 5–5. http://www.jstor.org/stable/24947406

[15] MRS Creese and TM Creese (1998). Ladies in the laboratory? American and British women in science, 1800–1900: a study of their contribution to research. Scarecrow Press.

[16] Perlin, John (2019) A Foote-Note on the hidden history of climate science: why you have never heard of Eunice Foote. Resilience.

[17] Perkowitz, Sydney (2019). If Only 19th-Century America Had Listened to a Woman Scientist. Nautilus (78).

[18] Shapiro, Maura (2021). Eunice Newton Foote's nearly forgotten discovery. Physics Today. AIP Publishing LLC. doi:10.1063/PT.6.4.20210823a.

[19] Mrs Elisha Foote (1858). On a new source of electrical excitation, Philosophy Magazine(15, 239–240).

[20] DJ Kevles (2001). Physicists: the history of a scientific community in modern America. Harvard University Press, p. 7.

[21] Fleming, JR (1999). Joseph Fourier, the "greenhouse effect", and the quest for a universal theory of terrestrial temperatures. Endeavor. 23(2):72–75. doi:10.1016/s0160-9327(99)01210-7.

[22] Harris, DC (2010). Charles David Keeling and the story of atmospheric CO2 measurements. Analytical Chemistry. 82(19):7865-70. doi:10.1021/ac1001492.

[23] Mitchell, Jeff (2018). Science Knows No Gender: In Search of Eunice Foote Who 162 Years Ago Discovered the Principal Cause of Global Warming. The Current. University of California, Santa Barbara.

[24] https://www.noaa.gov

[25] https://womenleadclimate.org

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