This article is a preview from the Spring 2020 edition of New Humanist
There is a lab on the north slope of the Mauna Loa volcano in Hawaii which measures carbon dioxide in the atmosphere. It has been doing this, almost without a pause, since 1958. Plot the data from this lab over time and you get one of the most iconic graphs in climate change: the Keeling Curve. It is named after the scientist who first established the research, David Keeling, and his curve is, unsurprisingly, going up. When the project began, the team found 315 parts of carbon dioxide for every million parts of atmosphere (ppm, or parts per million). Last May, it hit over 415ppm.
As citizens of the 21st century, carbon dioxide haunts our lives. Footprints, emissions, offsets, budgets, fights over whether we need to give up meat or flying (spoiler: you probably do), and a gripping fear about what it means for the future. We learn from an early age that humans breathe in oxygen and breathe out carbon dioxide – two carbon atoms nestled with one of oxygen. We know other animals do the same, and plants do things the other way around. It is part of how we understand the world around us.
But until the middle of the 18th century, no one realised that carbon dioxide existed at all. For our ancestors, air was just air. It might be damp, smelly or noxious, and perhaps the air up near the gods – “aether” – was special in some way. But there wasn’t an understanding that air is made up of a variety of changeable gases.
In 1754 Joseph Black, a medical student at the University of Edinburgh, was investigating treatments for kidney stones when he identified what he called “fixed air” – a gas which put out a piece of burning paper almost as if it had been submerged in water. Roll on a decade or so and dissident theologian and chemist Joseph Priestley found himself in temporary lodgings next to a brewery in Leeds. With giant vats of fermenting liquid next door, he discovered he could suffuse water with this fixed air, giving it a pleasant fizz similar to mineral waters found in spa towns.
Not long after, Priestley identified another gas, which he’d call “dephlogisticated air” (we now know it as oxygen), and put it to work exploring how and why things breathe and burn. Manchester-based physician Thomas Henry joked it might become “as fashionable as French wine at the fashionable taverns”, with people sipping this new air instead of claret. He clearly saw something in these new gases, because in a few years he had a factory manufacturing carbonated waters. Another physician, John Mervyn Nooth, presented a device for producing a carbon dioxide-rich water at the Royal Society in 1774. This sold in large numbers and was the basis for the first artificially carbonated waters produced in the US, when chemistry professor Benjamin Silliman first started selling soda waters to hungover students at Yale. Priestley convinced the Navy that fizzing water might be a useful weapon in the fight against scurvy. The association with health continued into the 19th century, when carbonated water merchants like Johann Schweppe added herbal syrups, picked for their apparent medicinal qualities.
The new chemistry research of the time wasn’t just exploding the old alchemical concept of air, but that of fire too. Black moved on to a post at the University of Glasgow and, after the whisky industry asked his advice on cost-cutting, started investigating how liquids changed state – water to steam, or ice to water – leading him to develop the idea of latent heat. This in turn helped the university’s
scientific instrument maker, James Watt, to improve a model steam engine in their collection, kick-starting a process of technological change that would soon send atmospheric carbon dioxide levels soaring.
Before Watt, steam engines were rather lumbering bits of kit, only really useful for pumping water out of mines. After a few decades of tinkering (not to mention some canny games with patent law) Watt had machines which weren’t just more efficient but rotated, as well as moving up and down, making them applicable to a broad range of industries, from iron, cotton and brewing to the Royal Mint. In 1786, Watt and his business partner Matthew Boulton opened the world’s first steam-powered flour mill, in central London (near where the Tate Modern is today). Plagued with technical problems behind the scenes, it notoriously burnt down in 1791, amidst rumours of arson; the blackened ruin was a likely inspiration for Blake’s “dark satanic mills”. Still, some of the PR sparkle had stuck, and soon Boulton and Watt were selling their wares around the world.
Before long, cities from Manchester to Pittsburgh were coating themselves in soot not only via coal-powered factories, but coal-gas lighting, coal-powered trains and even coal-based electricity. The modern oil and gas industry was close behind, building on the infrastructure that coal had established. The rest is history – and a couple of hundred ppm extra CO2.
This new interest in airs and fires also gave us the means to discover global warming, even if it wasn’t until the last few decades of the 20th century that anyone would worry about it much. In 1827, French physicist Joseph Fourier gave us an idea of the Earth wrapped in an insulating atmosphere of gases which functioned like a jacket, keeping us warm. He described it as working a bit like a solar oven, but subsequent generations of scientists dubbed it “the greenhouse effect”.
It was Eunice Newton Foote, an American scientist and women’s rights campaigner living in New York state, who first identified the link between carbon dioxide and global warming. Experimenting with a couple of cylinders of gas she left by a window one sunny winter morning in 1856, she noticed carbon dioxide held the heat of the sun especially well. Writing up her experiment on the warming impact of carbon dioxide, she concluded, almost in passing: “An atmosphere of that gas would give to our Earth a high temperature.” Despite its being presented at a meeting of the American Association for the Advancement of Science and mentioned in a Scientific American write-up of the event, no one really paid any attention. A clue as to why might be found in the heading the Scientific American gave the article: “Scientific ladies”.
Luckily for Victorian science, a man came along soon afterwards and said exactly the same thing, so people listened. John Tyndall presented his work at a Royal Institution event chaired by Prince Albert, and his subsequent book Heat: A Mode of Motion was a bestseller. Climate change was mainstream science, even then; but it was largely theory for the Victorians. People didn’t see it as an immediate problem – and wouldn’t for another hundred years.
We were already on our way to warming the planet at that point, though no one at the time could spot it. With the benefits of modern science, we now know the Arctic started warming as early as the 1830s. In fact, we humans were messing with the carbon cycle well before Watt started playing with steam engines. As Mark Maslin and Simon Lewis note in their 2018 book The Human Planet, there was a noticeable dip in atmospheric carbon back in 1610. They ascribe this to the deaths of tens of millions of indigenous people in the Americas following colonisation by Europeans. The dead don’t farm, so the land started to turn into forests, breathing in carbon dioxide. Until the new European settlers felled the trees (not to mention discovering fossil fuels and laying down oil and gas pipelines) it gave a brief reprieve for carbon dioxide levels.
As the 19th century came to a close, the work of Fourier and Tyndall was picked up by Swedish scientist Svante Arrhenius. His friends at the Stockholm Physics Society had been fighting over the causes of Ice Ages, and Arrhenius picked up Fourier’s work on terrestrial heat to see if that would give him something new to present to the society. He was also going through a difficult divorce, and apparently found temperature calculations soothing. For months, he scribbled away, eventually calculating that doubling carbon dioxide emissions could raise the Earth’s temperature by five or even six degrees Celsius. Still, Arrhenius wasn’t too worried. He both under- and over-estimated humans, thinking we probably wouldn’t ever emit that much carbon, and even if we did, we’d find a way to solve the problem. (For trivia fans, Arrhenius is also a relative of Greta Thunberg.)
In 1938, an English steam engineer named Guy Callendar looked at the question again. Climate science was a hobby for Callendar, when he wasn’t busy in his day job in a secret defence lab in Sussex. Crunching the slightly better data available by then, he showed that as we’d been pumping out carbon dioxide, global temperatures had risen about a third of a degree Celsius. He presented this work to the Royal Meteorological Society, but they largely dismissed him. Like Arrhenius, Callendar wasn’t too concerned. The following year, the Second World War broke out. Callendar specialised in petroleum warfare and shared a patent for something called FIDO, which would burn thousands of gallons of petrol at a time to help aircraft land in fog.
After the war, a new generation of scientists were armed with better equipment, techniques and funding, much of it off the back of the Manhattan Project and the Cold War. As time had crept on, so had carbon emissions and global temperature. Foote’s idea that an atmosphere filling up with carbon dioxide would increase global temperatures was now much plainer to see. International Geophysical Year in 1957 was a worldwide programme of research with a side-portion of Cold War politics, kicking off with the launch of Sputnik. It provided a particular opportunity, and it was through this that Keeling’s Mauna Loa lab got its first wave of funding.
Climate change was raised periodically in the 1960s and 1970s. Congressional testimony from Nasa scientist James Hansen in 1988, and a UN speech from Margaret Thatcher in 1989, helped push it up the global agenda. The Intergovernmental Panel on Climate Change was established around the same time, publishing its first report in 1990, laying the ground for the 1992 Rio Earth Summit and establishment of the United Nations Framework Convention on Climate Change. Since 1995 it has convened international climate talks, the three most famous being 1997 in Kyoto, 2009 in Copenhagen and 2015 in Paris.
This new political interest in climate action worried those keen to maintain our addiction to fossil fuels. As Erik M. Conway and Naomi Oreskes outline in their 2010 book Merchants of Doubt, a PR playbook that was developed to seed doubt about links between tobacco and cancer was now applied to carbon dioxide and climate change; weaponising the uncertainty and critique which is part and parcel of robust modern science.
When it comes to the future of our relationship with carbon dioxide, the only thing that’s certain is that emissions are still going up, and the impacts is already hurting people.
There are companies developing ever more ingenious ways to suck carbon dioxide from the air and turn it into marketable products. In California, scientists are working to develop trees with roots especially good at absorbing carbon dioxide. Initiatives like these may well be part of the picture, but they won’t save us alone. On a cultural and political level, more and more people are reducing high-carbon behaviours like meat-eating, flying and car-owning, and demanding greater action from their politicians. But there is still a long way to go.
In all of this, it’s vital to remember the differentials of carbon pollution. Oxfam reckons the average Brit emitted more carbon in the first two weeks of 2020 than the citizens of seven African nations emit in a year, and even within these “average Brit” numbers, 70 per cent of flights are taken by just 15 per cent of the population. On top of this, globally poorer people are most likely to suffer the negative impacts of both climate change and the extraction of fossil fuels, whilst the rich reap the advantages. The politics of carbon dioxide are increasingly obvious in global inequality. Some campaigners even talk of “CO2lonialism”.
The 2015 climate talks in Paris saw belatedly agreement to try to curtail emissions enough to keep to a temperature rise of 1.5°C, after years of acting as if 2°C was somehow safe. For context, we’re currently at around 1°C. For many people around the world that’s already catastrophic.
A major round of UN climate talks will take place in the UK this November. Here, countries – particularly the richer ones – will be asked to ramp up ambition, and drastically cut carbon emissions. Totting up the 2015 Paris pledges, the UN has warned that we’re still on course for temperature rises of over 3°C. It is questionable whether we’ll even come close to meeting those pledges. If we do not rise to that challenge, the increasing carbon count at Mauna Loa will not be the only consequence.
