Unravelling a Vicious Cycle: Extreme Weather Events, Urban Expansion, and Deforestation

We statistically analyse the link between extreme weather events, urban expansion, and tree cover loss in a data set of regions in 163 countries from 2001 to 2018. While previous research has focused on these phenomena individually, we provide quantitative evidence on the chain of events in a whole cycle. A simultaneous equation model allows us to capture the interrelations and to quantify their strength. We show how droughts and floods can drive urban expansion, triggering deforestation, which in turn increases vulnerability to disasters. In a heterogeneity analysis across continents and levels of development, we uncover differences in the strength of the cycle and the statistical significance of its links. These findings emphasize the need for targeted, region-specific adaptation policies. We stress the importance of multilevel governance and land use planning to balance urban growth, environmental sustainability, and disaster impact reduction.