Dubai skyscrapers. Credit: Zsuzsanna Schreck

+ With global population growth slowing, I think that cities must plan for scenarios where populations shrink in the long term.

Current UN projections show that there will be 11 billion people living on Earth by the end of the 21st century. With the global population also urbanising, this is certainly something cities need to be preparing for. But should they also be looking further ahead?

It now seems that population growth may be slowing overall, and is not equally distributed across the globe. Faster-than-anticipated demographic transitions could lead to the world’s population stabilising and eventually decreasing. Increasing wealth and education appear to be reducing birth rates in many countries – leading to aging and, eventually, shrinking populations.

So what does this mean for cities? Well, shrinking cities are not new in the industrialised world. The North of England, the US Rust Belt and Eastern Germany have seen city populations shrink as people moved away from areas of industrial decline. 

However, what’s predicted is something very different. These new demographic trends will result in a wholesale decline in the population rather than local migration. And this will happen in places whose populations are currently booming. 

Cities in the Middle East, for example, have seen exploding native and migrant populations. These have been fuelled by oil and gas riches in the case of places like the United Arab Emirates (UAE) and Qatar, and improved public health and food production in countries such as Egypt. 

Between 1990 and 2010 the resident populations of the UAE and Qatar have grown by 315% and 271% respectively. To cope with this explosion, the capital cities of both countries have strategies in place that stretch to 2030. But what will these places be like in 2100? 

If the predictions are right, they could well experience falling population. So maybe these countries should be creating temporary cities to cope with current population booms – cities that could eventually be abandoned when their population starts to decline? 

Egypt is developing cities in the desert to accommodate its growing population and to prevent existing population centres sprawling over vital agricultural land in the fertile Nile Delta. Should some of the desert cities be designed to become obsolete in 100 years once Egypt’s population begins to decline? 

When we design and build new places elsewhere in the world, perhaps we should consider including a temporary element? Because I think that cities must plan for scenarios where populations shrink in the long term.