Creating more healthy and extra sustainable cities has develop into a world precedence integral to reaching the United Nation’s Sustainable Growth Targets and the World Well being Group’s well being fairness objectives. With 56% of the worldwide inhabitants now dwelling in city areas (with far greater charges in North America, South America, and Europe), metropolis and nationwide leaders might want to get critical concerning the sorts of bodily designs that may enhance public well being, city fairness, and sustainability.
However what do wholesome, sustainable cities appear to be? Widespread parts embrace secure and inexpensive housing, walkable streets, helpful public transit, and entry to every day dwelling wants and inexperienced areas. Utilizing indicators of those sorts of city traits can enable planners to focus on interventions, examine their efficiency to different cities (benchmarking), and measure progress towards objectives over time (monitoring).
Sadly, spatial indicators are onerous to create. First, indicators are wanted at each the neighborhood and metropolis scale to conduct within-city and between-city analyses. Second, the mandatory information don’t all the time exist, and the info that do exist is probably not publicly out there or constant. Third, superior spatial evaluation requires technical experience, costly software program, and plenty of information—obstacles in each metropolis, however significantly so in less-resourced locations. The web result’s a dearth of constant, reproducible indicators for wholesome, sustainable cities.
We want a brand new approach ahead. In a latest undertaking, my colleagues and I got down to handle this drawback with new, reproducible instruments to calculate city indicators extra persistently all over the world. We convened a world community of collaborators for information sourcing and validation of our enter and output information. This was essential as a result of we relied closely on open information, together with the International Human Settlement Layer (for city boundaries), OpenStreetMap (for road networks and facilities), and the Common Transit Feed Specification (for public transit stops and timings). We developed free, open-source software program to course of the info and calculate indicators derived from the UN’s sustainable improvement objectives. And anybody can repurpose this software program wherever on the earth.
This work just lately culminated in a collection of articles on city design, transport, and well being revealed in The Lancet International Well being. The flexibility to benchmark and monitor cities throughout the planet revealed a tough fact: Metropolis leaders and their companions should do extra to construct wholesome and sustainable locations.
We first labored with our worldwide collaborators to investigate city insurance policies and calculate constructed atmosphere indicators for 25 cities throughout six continents to evaluate walkability and accessibility. Our evaluation revealed many alternatives for enchancment. Cities typically adopted insurance policies that: 1) have been inconsistent with public well being proof; 2) have been much more probably to make use of rhetoric that endorsed well being and sustainability objectives than undertake measurable coverage targets; and three) left substantial implementation gaps.
Given the gaps between aspiration and efficiency—and the capability constraints going through most metropolis governments—we got down to develop open-source software program instruments to calculate indicators of walkability and accessibility all over the world. The outcomes are hanging.
Determine 3 exhibits our native walkability index. The colour scale represents commonplace deviations with zero as international common; greater values point out higher walkability and decrease values point out worse walkability. This reveals much less a narrative about higher-income versus lower-income international locations’ cities, and extra a narrative about completely different “fashions” of city planning. Older internal cities are usually extra walkable; newer outer suburbs much less so. Excessive-income European cities are inclined to carry out nicely, whereas high-income cites within the U.S., Australia, and New Zealand are inclined to carry out poorly.
How can we clarify this? In our coverage evaluation, we discovered that Australian and U.S. cities have been the probably to have transport insurance policies that favor automobile use over energetic transport similar to strolling and biking, and U.S. cities specifically have fallen additional behind fashionable international objectives for public transit entry.
São Paulo and Bangkok provide one other attention-grabbing story. The previous demonstrates good citywide efficiency, whereas the latter displays poor entry outdoors of the central metropolis. This additionally matches our coverage evaluation’s discovering that Bangkok had the best coverage gaps and limitations, whereas São Paulo’s coverage framework carried out higher than even these of many cities in high-income international locations.
These patterns might be explored in additional depth by analyzing walkable entry to 2 essential city facilities: wholesome meals markets and public transit stops. On the whole, European cities scored significantly nicely on entry to wholesome meals markets, whereas U.S. cities scored significantly poorly. For instance, 70% of Bern, Switzerland’s inhabitants is inside a 500-meter stroll of a wholesome meals market, however solely 6% of Phoenix’s inhabitants is. Most cities home greater than 60% of their inhabitants inside a 500-meter stroll of a public transit cease, however it’s noteworthy that three specific cities scored poorly: Mexico Metropolis; Maiduguri, Nigeria; and Chennai, India. It’s because casual collective transport performs an essential position in every of those cities’ mobility patterns, and information to trace it are missing. This stays an essential problem in benchmarking and monitoring cities.
City planners can assist wholesome, sustainable existence by offering constructed environments conducive to bodily exercise. However do they? We estimated thresholds of constructed atmosphere traits that assist the World Well being Group’s aim of a 15% discount in inadequate bodily exercise by strolling. Then we measured what quantity of the inhabitants lives in neighborhoods that meet these thresholds. Throughout the cities we studied, 59% of the inhabitants met the road intersection density threshold, with practically even efficiency between middle-income and high-income cities. Fifty-two % of the inhabitants met the inhabitants density threshold, although erratically so, with 97% assembly the edge in middle-income international locations however solely 38% in high-income international locations. The numbers range, however they’re all far beneath the place they need to be from a public well being perspective.
The place can we go from right here? Our examine developed open-source software program and open information at the side of native collaborators in order that, for the primary time, metropolis leaders can each benchmark their progress towards different cities and monitor that progress over time. These instruments create a brand new alternative to focus on evidence-based planning interventions, monitor coverage results, and harness classes discovered from peer cities.
The collection of articles is free and open entry, as is our software program. We now have concurrently launched the International Observatory of Wholesome and Sustainable Cities to advance wholesome and sustainable city planning, benchmark and monitor cities’ progress, and share extra constant, comparable city information to which anybody can contribute. The Observatory additionally hosts scorecards for every of the cities within the undertaking; Determine 4 exhibits an instance scorecard for São Paulo.
This undertaking demonstrated how we are able to monitor wholesome and sustainable cities all over the world. Nevertheless it requires worldwide effort to proceed measuring and monitoring cities. Organizations just like the UN and the World Well being Group play a key position in sustaining this, as do native, regional, and nationwide governments who can use this framework, contain native populations in crowdsourcing information, fill info gaps, and contribute to the open commons and rising open information platforms.
Few cities in our examine had measurable coverage requirements and targets to truly construct more healthy and extra sustainable cities, and their health-supportive constructed atmosphere options have been typically insufficient or inequitably distributed. We should work collectively throughout geographies and in any respect ranges of presidency to raised foster wholesome, sustainable cities for all.