How did we find out about climate change?

This is the story of the long and reasoned road to accepting the reality of climate science. How is it possible that some people, when the total human population was under a billion, understood the coming clash between Human needs and our planet’s finite resources?

Now that we are seven times more numerous, the threat feels (and is) very real. Some signs just can’t be missed. The disappearance of 75% of all terrestrial animals, coral bleaching or coastal dead zones are irrefutable proofs of changing conditions of life on our planet — not for the better.

The scarcity of early days

Concerns about the needs of a growing population and insufficient resources are nothing new. Scarcity was a harsh and hard reality for the vast majority of the population before the modern agricultural revolution. It is no surprise that some already considered the planet to be limited when there was so little to share.

On a local scale, many very different cultures had understood the integration of mankind with a greater web of life. Amazon Shuar tribes never killed animals unfairly, and the Maori have a word “Kaitiakitanga” for the bond of trust and guardianship between Men, the ocean, the sky and the land. The Maori considered themselves protectors, rather than predators of natural resources.

The insolvable population bomb problem

Fast-forward to the XVIII century in England. The very dawn of the industrial revolution. The transition from a pre-industrial rural system to the advent of factories and trains in less than 50 years did shake certainties about the global capacity of Humans to impact the environment. Suddenly, masses of Men from all regions flowed into demographic centres who had an ever growing appetite for resources and infrastructures.

Thomas Robert Malthus said in his 1798 book 'An Essay on the Principles of Population' (still a bestseller) that if the food production grew linearly, the population growth was exponential. Eventually, the Human population being limited only by religion, war and scarcity, would decrease because of dwindling resources. The famous “Malthusian catastrophe” in the making. The question was — and remains — will we reach this tipping point, and if yes, when?

Proving the human-induced part of climate change

Not a hundred years later, Swedish scientist, and man that looks like you broke his ancient Chinese flower vase, Svante Arrhenius proved that human activity induced large enough changes in CO₂ concentration to have an impact on global climate.

But these had only been debates reserved to the high spheres of paleo-climatologists and mathematicians. If scientists had reached the general consensus that human activity did induce modifications to the climate, they did not agree however on how it modified it.

The great acceleration

In the meantime, humanity had invented fertilisers, inaugurated the Persian oil fields, and been through two world wars. The era of cheap goods and consumption products was well underway, and nothing seemed to be about to stop it, especially not the harbinger predictions of obscure shifts in climate.

Sure enough, carbon emissions had not been the only thing released into the atmosphere.

Aerosols (like smog), who have a strong cooling power, were a much bigger public health issue at the time.

By the 70s, all the evidence had been gathered, and studies that still hold true today were already being published in universities and think tanks.

“The increase of 25% CO₂ expected by the end of the century therefore corresponds to an increase of 0.6°C in the world temperature — an amount somewhat greater than the climatic variation of recent centuries.”

— John Sawyer, 1972, in his meta study Man-made Carbon Dioxide and the “Greenhouse” Effect.

Plant the future

2016 was the hottest year on record, beating 2015, which had beat 2014 in those books. In fact, all ten hottest years happened since 1998. Human-induced planetary change is not a debate but a reality now.

Today, climate skeptics have had to renounce to some arguments. The last of these Mohicans are in the White House. But History -and reasonable, yet determined people – will brush them aside.

Snow is no proof, scientific research is. Scientists have done their job of discovering, doubting, weighting and proving the reality that is now ours. They are only the messengers.

What about the future? It is being written every day by each and everyone of us simultaneously. As we buy products, make choices based on environmental criteria, and engage in action that contribute to heal our planet, we change the direction of our society. Harbingering is as old as the world itself, but you know what is too? The creativity of Humans to save the day.