Why is it so easy to deny anthropogenic global warming?

Psychological Aspects of Climate Science Acceptance

In this blog post, physicist Arkadiy (Arky) Matsekh answers why some people deny global warming, while talking about the physics - and cups of tea.


Why is it so easy to deny anthropogenic global warming? In my opinion, it is in part because it’s very difficult for humans to understand complicated concepts. Most of us don’t have such inborn feature, we’re inborn hunters-gatherers, so we mostly hunt on and gather what the modern urban environments have to offer, without thinking too much about how exactly “the curl of the field, like a divergence, graduates itself along the spin” *.

For example (a very important one), it’s difficult to believe that a gas, present in the atmosphere in almost trace amounts, is a key green-house gas, and the increase of its concentration by, say 17%, is a very significant (if not catastrophic) effect. Because first of all, the units of concentration ppmv — parts per million by volume (in dry air) intuitively seem so miniscule, that it is simply hard to convince oneself of its significant influence on the atmosphere.



For example, we had 355 parts per million 30 years ago, and now we have what? 415 ppm, the increase of a tiny 60 ppm, what’s the fuss? It’s still just 0.0415% afterall. How come such a huge atmosphere, consisting of 99% di-atomic nitrogen and oxygen, and a little less than 1% of atomic argon not create much of a warming effect? Meanwhile carbon dioxide, nearly non-existent in quantity in our breathing mix, can have the determining effect on the atmosphere?

However, let's start with the fact that few people who do not understand the essence of the greenhouse effect know that the atmosphere is mostly nitrogen (and will also barely think about properties of various molecules, and their different electrodynamic and quantum properties).

So, let’s have a look at our air composition:

N₂ — 78.08%;

O₂ — 20.95%;

Ar — 0.934%;

CO₂ — 0.0415% (and growing catastrophically in real time by ~1 ppm in 3-4 months).

Plus, exceptionally small quantities of other gasses, including highly-potent greenhouse gasses, such as methane and nitrous oxide, or freons – generally molecules containing combinations of various atoms. Large ones usually being highly potent.

The total of all concentrations above might be slightly different from 100%, due to uncertainties and differences in the concentration of each individual component by few to several orders of magnitude. This is normal.

Naturally, water is also a key greenhouse gas and the second product of burning hydrocarbons and coal, but it doesn’t live in the atmosphere for too long. We’re lucky, when it comes to water, the atmosphere can self-regulate itself and stabilises the content of gaseous water. Therefore, it’s nearly impossible to systematically accumulate large excesses of water in the air, unlike the case for long living components like carbon dioxide, nitrous oxide or methane. However, increase in other greenhouse gases and resulting heating up of the atmosphere, causes the increase of water vapour concentration, which amplifies the effect of heating the atmosphere, allowing even more water to be held by the air and in turn cause more heating. This is an example of a “feedback loop”.


Greenhouse gases are not necessarily pure evil: if we didn’t have them in the atmosphere (or there was no atmosphere at all), the mean temperature of the Earth’s surface would be about -15°C.

In reality the average Earth’s temperature is about +15°C (and I hope this number stays constant for as long as possible). Greenhouse gases make life possible, but we all know that it’s the dose that makes a poison. And as for greenhouse gases, carbon dioxide in particular, has an annoyingly narrow margin of safety (the difference in dosage between efficacy and lethality when this term is applied to drugs).

Now, going back to being in denial.

One of the factors fuelling climate science denial is a certain level of ideology. Say, for example, free-market ideology has been shown to be a good predictor of anthropogenic climate change denial. So, if we are talking about people, whose ideology sees climate change and, more importantly, climate action as unfavourable, the ideology doesn’t allow them to accept the fact that burning fossil fuels is bad; and they also can’t understand the physics intuitively, even the basics. Because almost always, advanced physics is nothing but intuitive.

In order to accept the fact that one doesn’t have enough knowledge to understand the essence of the matter is absolutely impossible, because our self-belief is very strong. This is simply what we are as thinking species. It’s very hard to subdue your own ego, especially because the importance and equal significance of personal “opinions” has been invariably promoted by our Western political systems. It’s not that freedom of speech and thought is bad, not at all — it’s an amazing achievement that should be by all means cherished; it promotes free thinking and ultimately science; but the ugly side-effect of it which has never been addressed properly — overestimation of one’s competences, overinflated egos and unjustified sense of self-importance.

When somebody believes very strongly in their own ideas, accepting the expertise of scientists means accepting the authority of scientific experts and following their advice. And this is especially the case when the scientific community’s findings and collective knowledge contradicts with deeply-held pre-existing beliefs, even worse — vested interests.


But what about studying physics? Well, first of all, it’s difficult, much more difficult than most people can imagine, plus social and economic aspects of our lives are generally not too education-friendly; second – any inflow of new information conflicts with pre-existing beliefs. And third: the idea of the great “conspiracy of scientists”: scientists and teachers (a.k.a. “lefties” and “greenies”) pushing their “agenda”, their research papers and textbooks, makes learning more about the situation difficult. Normally, ideology doesn’t even allow denialists to take a bit of interest and read the materials written by the “evil-minded” people of science and education (I hope you hear me saying this with my tongue in the cheek). Are they afraid that reading these texts can undermine their faith? Well, our psychology is rather odd, so it is quite possible…

Yet another important aspect worth mentioning — inaccessibility (low affordability) of quality education in many economically-significant countries.

And although everyday experience seems to suggest that if in a drink, such as tea, the particles that define its colour, smell and taste are present in boiling water in similar (if not smaller) quantities than carbon dioxide in the atmosphere - we can perfectly distinguish tea from plain hot water. And if, for example, we double the content of such particles, we again can easily spot the difference: the tea has become stronger and darker. But due to still, a very small “insignificant” content of “tea particles”.



Water in this case is the same inert carrier of seemingly insignificant admixture, which entirely defines the properties of teas as a drink; similarly, the atmosphere is an inert carrier of greenhouse gasses, who almost entirely define it’s heating (infrared radiation trapping) properties. The effect that we see from molecules of nitrogen and oxygen is only Rayleigh's scattering — blue colour of the sky and orange sunsets instead of black emptiness of space with the bright disk of the Sun. Not much for trapping heat here. But all the business with trapping and re-radiation of infrared radiation is done by greenhouse gasses.

Or another example — somebody had an episode of flatulence in an elevator. Colloquially, such an event is known as farting. The amount of gas released is about 50 ml for 8-10 meters cubed of the volume of the lift. Of those 50 ml of gas, the stinky component (mostly hydrogen sulphate) is only 1%, so for the total volume of the lift, this is a miniscule amount, apparently less than carbon dioxide in the atmosphere. Yet, in 10-15 seconds in all the parts of the lift it becomes perfectly clear that the air has been spoiled. Very small concentration of hydrogen sulphate defines the quality of the air in the lift and, if it increases critically, it starts to stink. Is it intuitive? Yes. Can it be derived from everyday experience? — also yes!

Now we transfer the same seemingly intuitive reasoning to the planet’s atmosphere and suddenly logic is lost. It’s hard for me to tell why, because it’s a direct analogy. We (humans), by our consumption (in this case by consumption of energy in the very broad sense) emit relatively small amounts of resulting products in comparison to the volume of the atmosphere. Well, “farting in the lift” and spoiling our common air.


And the logic kind of suggests that we should try to “fart in the lift” as little as possible: switch to energy sources that do not produce greenhouse gases, so as not to spoil the common air. Reduce the dependence of food production and supply systems on livestock. Walk away from wasteful production and consumption practices. But here we have a sharp denial of the relationship. Paradox! Paradox?!

By the way, carbon-free (low-carbon in general) energy sources and appropriate business practices exist and have been around for a long time. They are reliable and efficient; obstacles in transitioning to them are mainly political and social. Including, of course, denial. And if you don’t believe me, stay tuned for another post — time to dispel the myth of renewable energy inefficiency! Those myths downplaying the capacity of renewables are the new climate change denial.

P.S. Just in case. All volcanoes on the planet emit on average ≈280 megatons of equivalent carbon dioxide per year, while human civilization - more than 40 gigatons (140-150 times more). To a large extent, this is a result of burning fossil fuels. Humans have been the dominant source of excess greenhouse gases in the atmosphere for well over a century and in the past few decades this effect has reached a catastrophic, ever accelerating rate.

*Strugatsky Brothers — “Monday Begins on Saturday”, “Tale of the Troika”

Tale of the Troika - Wikipedia

Monday Begins on Saturday - Wikipedia