People often speak metaphorically of the heartbeat or pulse of a city, but according to the authors, a new paper According to the report published in the journal Proceedings of the National Academy of Sciences, cities indeed have an “urban pulse” — an indicator of a city’s “metabolic activity” that can in turn be measured to reveal explanatory patterns. And these examples can help inform future public policy on urban planning.
The exact definition of urbanization has changed over the centuries. Zhe Zhu of the University of Connecticut and his colleagues adopted an expanded version for their study. It reflects fundamental “parallel processes of change in at least six dimensions, including demography, economy, infrastructure, environment, governance, and culture,” they wrote. “Together, they lead to outcomes such as population growth, urban expansion, GDP growth, and innovation, measurable outcomes of the process.” Their chosen dimensions reflect this dynamic picture: Cities are not static networks but “living, adaptive ecosystems.”
“For decades, we’ve been capturing the result of urbanization—a house built or a road widened.” Zhu said. “But you don’t really see the dynamics in the urban area. It’s going to be a very powerful tool that affects not only the top-down policy decisions of governments, but also the bottom-up decisions of everyday people walking through their cities.” One day, for example, we can check the “urban pulse” of a neighborhood when house hunting or scouting potential locations for a new business.
Advances in remote sensing and various analytical techniques make it possible to collect multidimensional data from a variety of sources, such as satellite images or geolocated mobile or social media data. Zhu et al. They drew their data from NASA Harmonized Landsat and Sentinel-2 databases to analyze new construction, renovations, infrastructure upgrades, green space expansions and demolitions in Seattle, Shenzhen, Lagos, Mumbai, Dubai and Mexico City.
Three basic vital signs
Their analysis revealed three distinct “vital signs” for monitoring cities. First, urbanization is a “spike”: There are sharp, short-term spikes in activity, not smooth continuous growth. According to the authors, the best example of this is Dubai, whose waterfront areas have seen huge leaps in redevelopment activity – particularly capital-intensive projects such as luxury towers or mixed-use buildings. Shenzhen’s booms, by contrast, were more concentrated, “reflecting the city’s capacity for rapid, state-led capital and construction mobilization,” they wrote.
