Updated: Jun 23, 2021
By Alessandro Armanna
Might the future make our cities uninhabitable? It’s time to go underground… Maybe
Building new cities below the ground can be an exciting idea in many ways, especially from an ecological and ergonomic perspective, but several questions arise: how will people react to this new artificial environment? What will be the effects on social life, and how happy will underground citizens be? Let’s get to the heart of the issue, with all its advantages and possible risks.
The discussion on sustainable cities is getting increasingly topical due to our society’s tremendous industrial, ecological, and social problems. It’s clear that recent years have seen booms in everyday awareness (pollution, climate, and mandatory recycling) and technological standards, such as solar panels, wind turbines and LED lights; among the latter, the most exciting upcoming innovation could be the “ecological concrete” and “sustainable cement”, which are capable of a massive cut in global carbon emissions.
However, all this may still not be enough, especially considering the increasing number of climate catastrophes is making life on Earth difficult. The most innovative idea – and the most stimulating according to social sciences, as it may represent a real revolution – is undoubtedly the idea of Underground Cities that are already developing worldwide.
A world growing underground
Cities like Montreal, Helsinki, Hong Kong and, above all, Singapore, which has an incredibly high population density (the highest in the world), have launched ambitious and extensive (and probably indispensable) “underground” programmes, supported by many favourable aspects.
So, what are the advantages of these underground cities?
1. Underground is a place safe from the worsening surface warming.
2. Saving power: temperature underground is more stable; moreover, you can take advantage of geothermal energy.
3. No problem with space to further enhance the cities.
4. Water available at any time, since it is absorbed by the soil after rain, it can be used for growing and harvesting vegetables.
5. Wide range of sustainable energy resources, such as solar panels and wind turbines (both on the Earth surface), and above all, geothermal energy, generated and stored in the subsoil.
6. Reduced environmental impact.
Don’t worry, be happy… if you can
What about the drawbacks? The psychological effect of life underground is still to be studied in detail, but one thing is for sure: people need to be prepared psychologically in advance before shifting underground. Since any urbanisation’s ultimate goal should be to “let people be happier”, the real difficulty is convincing people that living underground can be comfortable.
Although underground cities can represent a suitable solution to many problems, they would undoubtedly raise new ones, particularly from a biological and social perspective.
A clock inside us
It’s well-known that a protracted absence of light or the offset of a typical day/night cycle can significantly affect the circadian rhythms and our biological clock, which regulate our metabolism and our mood. The same effect is felt when we have a jet-lag experience.
In countries close to the polar circle where there are six months of perennial day and six months of uninterrupted night, there are notable cases of depression, anxiety, irritability, sadness, concentrating difficulties, tiredness, sleep disorders and mental health problems leading to a high number of suicides and other crimes, alcoholism, drug abuse.
These phenomena are classified, in the light cases, as “winter blues” or, in the most severe occurrences, SAD (Seasonal Affective Disorder syndrome), an acronym that needs no further explanation.
The percentage of suicides in rich and happy Scandinavian countries – primarily Greenland – is the highest globally. This fact is considered a direct negative consequence of the long-lasting polar nights’ stress.
Through evolutionary processes, our body has settled on a sleep/wake rhythm and therefore, a light/dark rhythm – that necessarily would cause imbalances when altered, both at the hormonal level (first of all modifying the rate of melatonin, a hormone produced by the pineal gland, and serotonin, the so-called “happy hormone”) and neurological level (all factors that affect mood, personality, and, ultimately, the entire social sphere of humans).
Master Clock: how the human circadian system works
When sunlight hits our retina, it induces a neuronal signal activating melanopsin production, a protein that operates on the part of the brain called the hypothalamus. This is where our “circadian clock” is located, or the so-called “master clock”.
The master clock comprises about 20,000 neurons, forming a structure called the suprachiasmatic nucleus, or SCN, which acts as a metronome.
The SCN receives direct inputs from the eyes, and from here, the hormonal messages regulate the rest of the body, such as glands and neurotransmitters.
Every organ in the body has a peripheral clock that is synchronised by the central signal. Even at the molecular level, the individual cells are equipped with an internal device, a "molecular clock" regulating genes' activity.
However, melanopsin is activated only by a specific frequency range of the light spectrum, particularly by sunlight; this is why, for example, artificial light (especially the incandescent bulbs) is not sufficient to stimulate the retinal photoreceptors properly.
United Citizens of the subsoil
What could be the psychological consequences of a life lived entirely underground, lit by artificial and not natural light, and independent of our “biological clock”? What could be the impact on mood, sociability, predisposition to contacts, and human relationships affecting the future “citizens of the subsoil”?
There are, of course, not enough scientific studies so far, but one thing is for sure: underground cities certainly offer advantages in perspective, but they may contain many question marks as well.