Urban Growth Over Time and Planning Choices
GeographyPopulation & SettlementAges 12–13
Use it with your class: students open it from a link or a QR code, with no account needed.
Next in Population & Settlement
A city seen from above: a historic core at the center, with built-up rings spreading outward along transport routes. Click Run to grow the population year by year and watch built-up area, city radius, congestion and pollution change with it. Change the population growth rate and pick a planning direction (unplanned sprawl, a protected greenbelt, transit-first, or satellite towns), then compare: with the same population, a planned city moves more smoothly, pollutes less, and keeps more green space. Click the map to inspect each ring.
Lesson: Urbanization: the process of urban growth and its resulting issues
What it shows
Urbanisation is the rise in the share of people living in towns and cities, together with the spread of built-up land into the surrounding countryside. In this model, a city's built-up area equals its population divided by an average density that depends on the planning choice, so compact planning keeps the radius smaller. Congestion and air pollution grow with population but fall when more trips are made by public transport, and a protected green ring lowers pollution further. The rings from the historic core to the fringe show how land use changes with distance from the centre.
How to use
Keep the Planning direction on Let it grow unplanned, press Run and watch the bars for built-up area, congestion and air pollution over several decades. Press Reset, choose another planning direction with the same Starting urban population and Urban population growth rate, and run again for the same number of years. Compare the city radius and the congestion level. Finally, raise the growth rate to see how quickly the problems build up.
Parameters you can change
- Starting urban population 0.3–10 million people
- Urban population growth rate 0.5–6 %/year
- Planning direction Let it grow unplanned, Keep a greenbelt around the city, Prioritize public transit, Develop satellite towns
- Simulation speed 0.5–10 years/s
Questions to explore
- With the same population, which Planning direction gives the lowest congestion level, and why?
- Why does the unplanned city cover a larger area than a transit-first city with the same population?
- How does a higher Urban population growth rate change the number of years before air pollution becomes severe?
