Satellite data reveals 'urban pulse' in six global cities

The study, published in the journal Proceedings of the National Academy of Sciences, found that urbanization is not a smooth, steady process but rather occurs in "spiky," cyclical, or asynchronous bursts. This "urban pulse" concept, inspired by human vital signs, can detect early signs of economic stress or stagnation before they escalate into crises.

Each city exhibited a unique pulse pattern. Shenzhen, a megacity that grew from a fishing village, displayed the highest magnitude of growth with massive, clustered spikes reflecting rapid, state-led development. Dubai showed significant growth driven by speculative, capital-intensive megaprojects. Lagos, Nigeria's largest city, had a fragmented pulse characterized by long inactive periods punctuated by brief surges. Seattle demonstrated a market-driven pulse of redevelopment and densification.

Mumbai and Mexico City proved to be more resilient, showing less disruption during global shocks like the COVID-19 pandemic. The researchers observed that the pandemic triggered a synchronized "cardiac arrest" in development worldwide, but the recovery varied significantly by city. Shenzhen rebounded rapidly after a sharp dip, while Lagos saw incremental changes, and Mumbai and Mexico City experienced minimal impact.

The researchers believe their method can serve as a diagnostic tool for urban planners and policymakers, enabling them to identify slowing development in specific neighborhoods and intervene early to prevent infrastructure collapse or economic decay, as well as to avoid overheating labor and material markets.