The share of the world population living in cities has increased over the last decade. While urbanization has plateaued in many higher-income countries, cities in lower-income countries are on track to keep growing substantially in the coming decades. A common hypothesis is that increasingly adverse climate conditions and weather shocks will induce urbanization through increased rural-to-urban migration. In my thesis chapter Droughts and the growth of cities, I study this hypothesis by empirically estimating the long-run relationship between droughts and city growth – measured using the footprint of cities – and find that local droughts lead to slower city growth. This suggests that on average, adverse weather shocks may not induce a reallocation of people towards cities.
In the chapter Rapid population growth and city shape, I explore the association between population growth and how a city grows. Using high-resolution data on the built environment within cities, I show that when cities experience periods of higher population growth, they grow in a different way compared to periods with lower population growth. Specifically, cities expand more in areas exposed to flood risk, tend to be lower built and are more informal.
These results suggest that there may be some scope to improve conditions for the growing urban populations to cope with environmental hazards, climate change and weather shocks, for example by preventative urban planning.