Eunice Foote: The first to measure the impact of carbon dioxide on the climate!

We often think of climate science as something that has only recently begun. The truth is, like most fields of science, it started a long time ago. Scientific progress is often a slow and tedious process, and climate science is no exception. From the discovery of carbon dioxide to the most sophisticated climate models, it took us a long time to get where we are today.

Unfortunately, many of the scientists who play a key role in this climate journey do not get the recognition they deserve. Take Eunice Newton Foote as an example.

Eunice Newton Foote.

Foote was born in 1819 in Connecticut, USA. She spent her childhood in New York and later attended classes in Troy Women's Seminary, a women-only institution of higher education. She married Elish Foote in 1841, and the couple were active in the suffering and abolitionist movements. They joined the 'Convention on the Rights of Women' and signed the 'Declaration of Sentiments' in 1848.

Eunice was also an inventor and an 'amateur' scientist, a brave endeavor in a time when women were rarely allowed to participate in science. However, one of her discoveries became instrumental in the field of climate science.

In 1856, Eunice conducted an experiment to explain why the air at low altitudes was warmer than in the mountains. At the time, scientists weren't sure about the issue, so she decided to test it out. She published her results in the American Journal of Arts and Sciences.

Foote placed two cylinders under the Sun and then placed them in the shade, each with a thermometer. She made sure that the experiment would start with both flasks at the same temperature. After three minutes, she took the temperature in both situations.

She found that thin air doesn't heat up as much as dense air, which explains the temperature difference between mountain peaks and valleys. She then compared the effects of humidity with the same device. To make sure the other cylinder was dry enough, she added calcium chloride. The result is a much warmer cylinder with moist air, as opposed to a dry cylinder. This is the first step to explaining processes in the atmosphere, water vapor is one of the greenhouse gases that sustain life on Earth.

But that's not all. Foote went further and studied the effects of carbon dioxide. The gas has a high heating effect. At this point, Eunice doesn't notice it, but with her measurements, the warming effect of the steam makes the temperature 6% higher, while the carbon dioxide container is 9% higher.

Surprisingly, Eunice's concluding paragraphs come with a simple inference about how the atmosphere will respond to an increase in CO2. She predicts that adding more gas will lead to an increase in temperature - which we know to be true. In addition, she also talks about the influence of carbon dioxide in the geological past, as scientists have discovered evidence that Earth's climate varied from time to time at that time.

We now know that during different geologic periods of the Earth, the climate was significantly warmer or colder. In fact, between the Permian and Triassic periods, CO2 concentrations were nearly 5 times higher than they are today, causing a 6ºC (10.8ºF) increase in temperatures.

Eunice Foote's discovery was taken to Scientific American in 1856, where it was presented by Joseph Henry at the Eighth Annual Meeting of the American Association for the Advancement of Science (AAAS).

Her research was mentioned in two reports in Europe, yet her name was largely ignored for over 100 years - until official scientific recognition for her observations in 2011. .

Credit for this discovery was once given to Dr. John Tyndall, an Irish physicist. He published his findings in 1861 explaining how radiation is absorbed (heat) and what radiation it is - infrared.

Dr. Tyndall was part of the editorial team of the journal that republished Foote's work. Maybe he didn't actually read the article, or just ignored it because it was an American scientist (a common practice among European scientists at the time), and or because of her gender. But it's possible he drew some inspiration from it, too - without quoting it.

It must be said that Tyndall's work is more advanced and precise. He has much better resources and uses the latest discoveries in physics that can support his hypothesis.

It's unfortunate that researchers like Foote don't get the recognition they deserve, but it's encouraging that the scientific community is finally starting to recognize some of these pioneers. There's still a lot of work to be done.