Who discovered the 'greenhouse effect'?
We’ve wrote a lot about inspirational people in this blog – people who have inspired us, people who we’ve celebrated in our shirt designs, technology that we’ve woven into the fabric, creating ‘smart shirts’ with CashCuff and much more.
This month our inspiration is a scientist who we all owe a great debt to, Svante Arrhenius, probably not a name you’ve heard mentioned too much unless you're a climate scientist? Well let’s change that, without the amazing work of Svante we’d be facing much greater environmental threat then we are currently, here’s why...
Who is Svante Arrhenius?
Arrhenius was a Swedish scientist who originally studied as a physicist, though he’s often referred to as a chemist as well (you’ll soon see why). Arrhenius was one of the founders of what’s called the science of physical chemistry.
This is the study of macroscopic and particulate phenomena within chemical systems. Physical chemistry uses terms and many of the principles, practices and concepts of physics such as motion, energy, force, time, thermodynamics, quantum chemistry, statistical mechanics, analytical dynamics and chemical equilibria. It sounds extremely complex even by modern standards, but what we want to share with you goes back a long way, it was over 130 years ago, when Arrhenius was studying and expressing theories about the world.
He was celebrated and recognised within his field and continues to be over time, he received the Nobel Prize for Chemistry in 1903, going on to become the first Swedish Nobel laureate.
Arrhenius was the first person to use the principles of ‘physical chemistry’ to estimate the extent to which increases in atmospheric CO2 were responsible for the Earth’s increasing surface temperature.
Arrhenius was born on 19th February 1859 near Uppsala, Kingdom of Sweden, United Kingdoms of Sweden and Norway. He was the only son of Svante Gustav and Carolina Thunberg Arrhenius.
It is recorded that the young Arrhenius was a fantastic observer, at the age of three Arrhenius taught himself to read, learning purely by observing his parents at work without any tuition. These observational skills expanded further, when watching his father, working on the numbers within his account books, Arrhenius developed a strong interest in maths, which in turn led to him becoming an arithmetical prodigy. This was a passion for Arrhenius, mathematical concepts, data analysis and their relationships/laws remained a major part of his entire life.
Arrhenius originally studied at the University of Uppsala, but he was disappointed with the lecturers, principally the head of physics and the only faculty member who could have supervised him in chemistry. So he left to study at the Physical Institute of the Swedish Academy of Sciences in Stockholm under the physicist Erik Edlund in 1881.
His university work focused on the conductivity of electrolytes. Clearly Arrhenius had a natural ability for science and maths, but he didn’t go through university without a few ghosts coming back to haunt him from his early days in Uppsala.
In 1884 he submitted a 150-page dissertation on electrolytic conductivity to Uppsala University towards his doctorate. His work didn’t impress the professors, one of whom he had previously shunned when he moved courses. The result was a below average mark, his paper was awarded a 4th-class degree.
Here we start to see some of Arrhenius’s drive and determination coming through, as his paper is awarded a low grade, he challenges the classification, a process which bares fruit, for his paper was later reclassified as 3rd-class. Probably not what he wanted, but a step in the right direction. But it doesn’t end there, several years later, extensions of his work would earn him the 1903 Nobel Prize in Chemistry. Which is astounding and goes to prove that sometimes it takes a little time for the rest of the world to catch up and recognise these innovations for what they are.
The 1884 thesis
Arrhenius put forward 56 theses in his 1884 dissertation, most of which would still be accepted today, over 130 years later, unchanged or with very minor modifications. The most important idea in the dissertation was his explanation of the fact that solid crystalline salts disassociate into paired charged particles when dissolved – the concept for which he won the 1903 Nobel Prize in Chemistry.
Geeky science bit
Arrhenius’s explanation was that in forming a solution, the salt disassociates into charged particles, to which Michael Faraday had given the name ions - many years earlier. Faraday’s belief had been that ions were produced in the process of electrolysis - an external direct current source of electricity was necessary to form ions.
Arrhenius proposed that, even in the absence of an electric current, aqueous solutions of salts contained ions. Thus proposed that chemical reactions in solution were reactions between ions.
His dissertation met with the same response from the professors at Uppsala -when he left their institution he had made some serious enemies who would seek revenge at every opportunity in his professional career.
So Arrhenius sent the work to a number of scientists in Europe who were developing the new science of physical chemistry, people such as Rudolf Clausius, Wilhelm Ostwald, and Jacobus van‘t Hoff. This group of scientists were impressed by Arrhenius’s work, particularly Wilhelm Ostwald who made the journey to Uppsala, as he wanted Arrhenius to join his research team.
But Arrhenius preferred to stay local, working in Uppsala, where he could also care for his father, who was old and frail. Whilst here he worked on an extension of his ionic theory, proposing definitions for acids and bases in 1884. He believed that acids were substances that produce hydrogen ions in solution and that bases were substances that produce hydroxide ions in solution.
In 1885, Arrhenius received a travel grant from the Swedish Academy of Sciences, which enabled him to study with several prominent scientists of the time - Ostwald in Latvia, Friedrich Kohlrausch in Würzburg, Germany, Ludwig Boltzmann in Graz, Austria and with Jacobus van‘t Hoff in Amsterdam.
By 1889, Arrhenius had demonstrated the fact that most reactions require added heat energy to proceed, formulating the concept of activation energy. This is the idea that there is an energy barrier that must be overcome before two molecules will react. Unsuprisingly this is called the Arrhenius equation, it gives the quantitative basis of the relationship between the activation energy and the rate at which a reaction proceeds.
As an innovative thinker, a pusher of boundaries, it feels like Arrhenius was a natural to become involved with, and set up the Nobel Institutes and the Nobel Prizes. His passion for science and innovation made him a great fit and the Nobel Institute became a significant part of his life.
He joined the Nobel Committee on Physics and became a de facto member of the Nobel Committee on Chemistry. He used these positions to arrange prizes for his friends (Jacobus van ‘t Hoff, Wilhelm Ostwald, Theodore Richards) and of course, he attempted to deny them to his enemies.
In 1901 Arrhenius was elected to the Swedish Academy of Sciences, against strong opposition – more battles with previous lecturers and professors, whom he never did make peace with.
Two years later, in 1903, he became the first Swede to be awarded the Nobel Prize in Chemistry and in 1905, upon the founding of the Nobel Institute for Physical Research at Stockholm, he was appointed rector of the institute, the position where he remained until retirement in 1927.
Laser focussed and driven
I think it’s fair to say that Arrhenius didn’t suffer fools. He was passionate about his work, when he felt that those around him didn’t understand or support where his work was taking him, he wasn’t afraid to look elsewhere and find people who did. People who shared his passion, who had a vision for the future.
That’s the background to the man who discovered the ‘Greenhouse effect’, now we’ll dive into the concept itself and how Arrhenius theorised it.
The greenhouse effect
While developing a theory to explain ice ages and inter-glacials in 1896, Arrhenius was the first to use basic principles of physical chemistry to calculate estimates of the extent to which increases in atmospheric carbon dioxide (CO2) would increase the Earth’s surface temperature through the greenhouse effect.
These calculations led him to conclude that human-created CO2 emissions from the use of fossil-fuels and other combustion processes, are large enough to cause global warming. This conclusion has been extensively tested, winning a place at the core of modern climate science.
Arrhenius built upon the existing work of other famous scientists, including Joseph Fourier, John Tyndall and Claude Pouillet. Arrhenius wanted to determine whether greenhouse gases could contribute to the explanation of the temperature variation between glacial and inter-glacial periods.
Arrhenius used infrared observations of the moon – by Frank Washington Very and Samuel Pierpont Langley at the Allegheny Observatory in Pittsburgh – to calculate how much infrared radiation (heat) is captured by CO2 and water (H2O) vapour in Earth’s atmosphere.
Using ‘Stefan’s law’ (better known as the Stefan–Boltzmann law), he formulated what he referred to as a ‘rule’. In its original form, Arrhenius’s rule reads as follows:
"If the quantity of carbonic acid increases in geometric progression, the augmentation of the temperature will increase nearly in arithmetic progression".
Based on information from his colleague Arvid Högbom, Arrhenius was the first person to predict that emissions of carbon dioxide from the burning of fossil fuels and other combustion processes were large enough to cause the effect we now know as global warming.
In his calculations Arrhenius included the feedback from changes in water vapor as well as latitudinal effects, but he omitted several influencial aspects such as clouds, convection of heat upward in the atmosphere and other essential factors. Despite these omissions, his work is now seen as the first demonstration that increases in atmospheric CO2 will cause global warming.
Challenging his thinking
Arrhenius’s absorption values for CO2 and his conclusions met with a lot of criticism, foremost of the critics was Knut Ångström in 1900, who published the first modern infrared absorption spectrum of CO2 with two absorption bands. These experimental results seemed to show that absorption of infrared radiation by the gas in the atmosphere was already “saturated” so that adding more would make no difference.
Arrhenius strongly disagreed and in 1901 he dismissed the critique altogether. There are not a lot of references to it, but he did touch on the subject briefly in a technical book titled ‘Lehrbuch der kosmischen Physik’ (1903), where he suggested that the human emissions of CO2 would be strong enough to prevent the world from entering a new ice age and that a warmer earth would be needed to feed the rapidly increasing population.
“To a certain extent the temperature of the earth’s surface, as we shall presently see, is conditioned by the properties of the atmosphere surrounding it, and particularly by the permeability of the latter for the rays of heat.”
That the atmospheric envelopes limit the heat losses from the planets had been suggested about 100 years earlier in 1800 by the great French physicist Fourier, whose ideas were further developed afterwards by Pouillet and Tyndall. Their theory has been called the ‘hot-house theory’, because they thought that the atmosphere acted in the same manner as the glass panes of hot-houses.
“If the quantity of carbonic acid (CO2 + H2O → H2CO3 (carbonic acid)) in the air should sink to one-half its present percentage, the temperature would fall by about 4°. Further reductions to one-quarter would reduce the temperature by 8°. The flip side of this was that any doubling of the percentage of carbon dioxide in the air would raise the temperature of the earth’s surface by 4°, and if the carbon dioxide were increased fourfold, the temperature would rise by 8°.”
“Although the sea, by absorbing carbonic acid, acts as a regulator of huge capacity, which takes up about five-sixths of the produced carbonic acid, we recognise that the slight percentage of carbonic acid in the atmosphere may, by the advances of industry, be changed to a noticeable degree in the course of a few centuries.”
“Since, now, warm ages have alternated with glacial periods, even after man appeared on the earth, we have to ask ourselves: Is it probable that we shall in the coming geological ages be visited by a new ice period that will drive us from our temperate countries into the hotter climates of Africa? There does not appear to be much ground for such an apprehension. The enormous combustion of coal by our industrial establishments suffices to increase the percentage of carbon dioxide in the air to a perceptible degree.”
“We often hear lamentations that the coal stored up in the earth is wasted by the present (C.1900) generation without any thought of the future, and we are terrified by the awful destruction of life and property which has followed the volcanic eruptions of our days. We may find a kind of consolation in the consideration that here, as in every other case, there is good mixed with the evil. By the influence of the increasing percentage of carbonic acid in the atmosphere, we may hope to enjoy ages with more equable and better climates, especially as regards the colder regions of the earth, ages when the earth will bring forth much more abundant crops than at present, for the benefit of rapidly propagating mankind.”
These remarks are fascinating, the effects of CO2 in the earth’s atmosphere were yet to be realised, Arrhenius thought it might bring with it more crops and that this could be beneficial! As we now know, the effect is much stronger and more pronounced than Arrhenius could have ever imagined, more pronounced than many of us could have imagined even just a few years ago, with the escalation in extreme climatic events that we have seen over the past 30 years it’s clear that the ‘green house effect’ is the biggest threat to our ways of life and our planet.
Let’s go back to the early twentieth century, at the time of Arrhenius writing his thesis the accepted consensus was that, historically, orbital forcing had set the timing for ice ages, with CO2 acting as an essential amplifying feedback element. However, CO2 releases into the atmosphere since the industrial revolution have increased to a level not found for over 10, maybe 15 million years, when the global average surface temperature was up to 11°F (6°C) warmer than what we know today and almost all glacial ice had melted, raising world sea-levels by about 100ft!
Arrhenius estimated based on the CO2 levels at his time, that reducing these levels by 0.62–0.55 would decrease temperatures by 4-5 °C and an increase of 2.5 to 3 times of CO2 would cause a temperature rise of 8-9°C in the Arctic region.
130 years later
We now know the reality of these assumptions, we are living through climate change.
The world now faces unprecedented environmental change, the objections that Arrhenius faced when he first theorised his concept have not gone away.
Thankfully there have been marked improvements in how we produce our energy as the reality of Climate Change is very much part of modern life. Unfortunately people continue to produce vast amounts of CO2 but there is hope, backed by science and innovation.
Game changing moment
In 1987 world leaders signed up to the Montreal protocol, this banned the use of CFC gases that had created a hole in the upper atmosphere, the Ozone layer. 34 years later and scientists who study these delicate areas of the planet have reported significant improvements to the damaged areas. Don’t get me wrong, it’s not fixed – that would be some type of miracle, this is a planet that we are talking about, the size, volume and time involved in everything planetary is HUGE, but we can see improvement, and that brings hope that if we change our behaviour we can impact the future, help the generations to come, protecting our planet.
The Ozone hole is receding, this is clear and demonstrable proof that when we work together - globally - we can achieve great things. I’d like to finish this post with a ‘Thank you to Arrhenius’, without his perseverance and dedication, our knowledge of the green house or hot house effect might not be what it is today.
I am in no doubt that he has played a pivotal role in our understanding of the impact that the consumption of fossil fuels has on the planet and it’s people and I thank him for not giving up, finding like-minded people, his tribe and pursuing his passion.
Why are we sharing this story?
It shares the environmental data from the past 800,000 years (Another big number). This story is about all of us, where we’ve been and the direction we will travel into the future. There’s never been a more important time to ‘show your stripes’, find out more about it here.