Chapter 3 - Spaceship Earth

Chapter Summary

If you were living in a small community on a spaceship and one astronaut started to use up all the supplies for themselves, it would jeopardise the mission. Things would be even worse if another shuttle arrived with more astronauts, but they turned up with no extra food, water, or other supplies.

This is a thought experiment.  The Earth is much larger than a spaceship, but it is just like a spaceship. It also has finite resources. It is a “Closed Mass System”.

Sustainability is rooted in the fact that our planet is finite, and it is not exempt from the laws of Physics. The Second Law of Thermodynamics is in play on our planet just like it is everywhere else in the universe. This means that, although the Earth was gifted with a fantastic array of raw materials, at some point, the usable level of these resources will run out. We inherited tonnes of precious metals and minerals from the guts of a supernova billions of years ago, but as we mine and manufacture our way into the future, we will eventually exhaust them.

So, supplies are limited, but the human population has been growing exponentially for centuries.

In 2020, 81 million people were added to the planet (a number roughly equal to the population of Germany). This growth rate of 1.3% annually would result in a population density of one person per square meter on the dry land surface of the Earth in 790 years. This is clearly an impossible situation. But well before even reaching this extreme, resources would be stretched and eventually reach a breaking point.

We do not need to wait hundreds of years to see the stress marks on the planet. Our spaceship is already under a lot of pressure. This chapter has some of the key details.