Different dimensions of urbanization in East African cities and towns

Cities across the world are developing rapidly. Many studies have analysed this development in a one-dimensional way, mostly focussing on demographics or land cover. Yet, urbanization is in fact a multi-dimensional process, also characterized by economic transitions, changes in lifestyles, and increased connectivity. Consequently, the relationships between these dimensions remain unclear. This study presents the first systematic quantification of urban development in different dimensions for a large number of settlements. Specifically, we quantified urbanization in five dimensions for all settlements with over 10,000 inhabitants in Kenya, Tanzania, and Uganda, using population, built-up land, and points-of-interest data on economic, social, and connectivity amenities. Our findings reveal medium to strong positive correlations (r = 0.54 to r = 0.76) between social, economic, and connectivity dimensions (all expressed per person), while others showed weak or no correlation. This suggests that different dimensions do not develop simultaneously, leading to varied urban profiles. Using K-means clustering, we identified six settlement types: a small cluster of metropoles, one type of medium-sized cities and four types of towns, which differ strongly in their physical, economic, social, and connectivity characteristics. These findings indicate that urban settlements develop in diverse ways with a high variation between the dimensions in smaller settlements. This highlights that threats and opportunities for sustainable urban development differ across settlements and require context-specific strategies while also drawing lessons from comparable settlements.