Simple population model
Contents
Here is an exercise for GSCE/A level Geography students developed for RIS (Researchers in Schools)
I like it because it speaks directly to the students' futures.
The UK is overpopulated in the sense that its current ecological footprint is significantly larger than its capacity. This means that its popultion is consuming more environmental resources than are actually available to it.
So are we all doomed? Let's find out.
Have a look at the data
The UK's current population represents a sort of high water mark, and is due to go into decline as its rapidly ageing population dies off leaving smaller numbers of younger people with low birth rates in its wake. This is something that happens all over the world as countries go through urbanisation and industrialisation. Coupled with this reduction in natural population growth is a pretty rapid reduction in environmental impact per unit of GDP production that’s been going on since the 1960's in the developed world.
Model
Students construct a simple iterative forecast model of the UK's population, GDP and ecological footprint on a spreadsheet, where people are born, have babies 30 years later and die when they are 80. Birth rates vary with GDP per capita, modified by the GINI coefficient. In the model, immigration is of people in their 20′s, about 10% of whom settle permanently and have children too, roughly what the UK has been doing over the last 20 years. All assumptions can be changed to investigate their impact.
Results & Conclusions
Provided there is
- some imminent reduction in income disparity (down to current Scandinavian levels) to boost GDP and birth rates
- the rapid convergence on today’s environmental state-of-the-art (also Scandinavian) continues
the trends suggest something like this:
=> By about 2100, the UK will end up with a sustainable population at roughly 40 million pretty well off people.
What an exciting time to be starting out!
