How we discovered the climate problem

How we discovered the climate problem

By connecting climate change to its material impact on the world, scientists have transformed an observation into a policy problem. The history of this discussion demonstrates the power of changing that narrative,  writes Will Grant from the Australian National Centre for the Public Awareness of Science.

In the 1820s Joseph Fourier – French mathematician, physicist, moderate revolutionary, and cravat-wearer – proposed an intellectual problem. The Earth, he declared, should be considerably colder. The solar radiation from the Sun, according to his calculations, was just not enough to keep the planet as warm as it was.

His solution? Amongst other things, he argued the Earth was kept warm by having an atmosphere. This was, though he never used the term, the first articulation of the concept of the greenhouse effect.

Jump forward a few years to 1837.

Louis Agassiz – Swiss-American biologist, geologist, comb-over-sporting, and noted racistin scientist’s clothing – observed something odd about our landscape. Contrary to dominant Biblical doctrine at the time, geological evidence pointed to the existence of ancient glaciers stretching across Europe and North America. In other words, the climate had been very different in the past.

Fast-forward again to 1859.

John Tyndall – Irish physicist, Fellow of the Royal Society, and spectacular Victorian-era beard-with-no-moustache kind of guy – added detail to Fourier’s concept of the warming atmosphere.

In particular, he found evidence showing that it was water vapour and carbon dioxide that trapped heat in the atmosphere.

 

At the end of the century, it was Svante Arrhenius – Swedish physicist, chemist, and Nobel Prize winner, who put the story together.

He argued that if quantities of carbonic acid – or CO2 for our purposes – in the atmosphere were to drop by half the current amount, then the Earth’s surface temperature would drop by 4 degrees. Conversely, if the concentration were to double, then it would warm by four degrees.

Arrhenius went on to suggest that human-caused emissions of CO2 from burning fossil fuels would raise the global temperature.

This is the skeleton of the key fact of climate change: that our planet is kept warm by greenhouse gases, and more of these gases makes the planet warmer. This took the best part of a century to uncover.

Let’s put some meat on that skeleton.

In 1938, Guy Stewart Callendar did just that when he compiled temperature measurements from the late 19th century onwards to show that, over the preceding 50 years, global land temperatures had increased. The globe, he showed, was warming.

Charles David Keeling continued the job. In 1961, he published data showing carbon dioxide levels were steadily rising. Dr Frankenstein’s climate monster was born – or so we thought.

In a graph, Google’s Ngram Viewer shows how often the terms ‘climate change’, ‘global warming’, and ‘greenhouse effect’ appeared in English language books between 1900 and 2008.

However imperfect, it’s basically a chart of how much people were talking about these terms, and by extension, how much they cared.

Conversely, it also shows that for a long time, humankind didn’t.

Indeed, those who first discussed climate change suggested it was probably a benign or beneficial phenomenon. Arrhenius, for example, suggested that the situation might improve for future generations.

Callendar, even though he had seen evidence of the warming, proposed it was good and that it would prevent a return of ‘deadly glaciers’ and would boost crop yields at higher latitudes.

Our first breakthroughs were very early. Arrhenius presented a first expression of the theory of global warming in 1896 and Callendar showed actual warming in 1938.

Yet the world barely registered. Barely anyone cared.

It was only in the 1970s that the world saw an uptick in the discussion, but it wasn’t until the late 1980s that the world really started to pay attention.

When we tell the history of the discovery of climate change, we tend to tell the story of factual, scientific discoveries: the story of Fourier, Arrhenius, and Callendar, as briefly described above. This story is important, but it’s inadequate.

It’s inadequate because the discovery of any problem requires more than just facts. A fact – even one as big and hairy as climate change – only becomes a problem when it is connected with values.

This process of connecting fact with value was crucial in the history of climate change, and it is crucial in the emergence of any problem.

For climate change, many argue that this connection happened in 1988 – the uptick in the Ngrams graph. That year, James Hansen, director of NASA’s Goddard Institute for Space Studies testified before the US Congress.

 

Speaking on a very hot summer day in the Capitol, Hansen declared he was ‘99 per cent’ certain global warming was happening, and that the situation was dire enough to affect the likelihood of extreme weather events.

Hansen played a key role in the final emergence of climate change as a problem, rather than simply a fact, and he did so by connecting it to its value. Yet like so many scientists bringing values into their communication, he saw criticism from his scientific colleagues.

When the world was listening, Hansen told a story of how climate change facts threatened things we value. His testimony made front-page news around the world and kicked off a public relations fight that continues today.

Perhaps we weren’t ready to care about climate change before this, perhaps other problems were more pressing. But James Hansen and others working at the time made more people care about the issue that day by connecting the facts to their value, and the real threat they pose.

So often, researchers focus on facts alone. But facts aren’t enough. If there truly is a problem, then it’s part of the job to make people care. Weave values and facts, tell the story – only then will people listen.

 

This piece was first published at Policy Forum, Asia and the Pacific’s platform for public policy analysis and opinion. Read the original here: https://www.policyforum.net/how-we-discovered-the-climate-problem/

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