What is the best way to build a city, both for human health and for the environment? This is what a recent study led by the Barcelona Institute for Global Health (ISGlobal) has tried to answer. To do this, they have analysed 919 European cities and identified four basic urban configurations:
- Compact high-density cities (such as Barcelona, Milan, Paris or Basel) – 68 million people live in them globally.
- Open cities of low height and medium density (such as Brussels, Dublin or Leipzig) – 56 million people live there
- Low-height, low-density open cities (such as Pisa, Oviedo or Toulouse) – 38.5 million people live there
- Low-density green cities (such as Helsinki, Rennes, Aarhus or Stockholm) – 27.5 million people live there
The first two types of city are those that tend to have higher levels of exposure to air pollution and urban heat island effects. Consequently, they also present the highest mortality rates. On the positive side, the concentration of people and services in a smaller space leads to a greater energy efficiency, which makes compact cities the ones with the lowest carbon footprint.
In contrast, low-density green cities showed the lowest levels of urban heat island effect, air pollution and mortality rates. But, as dispersed urban agglomerations, they require longer journeys and are less energy efficient, with the most expensive per capita carbon footprint.
Compact cities are the model of the future for cities, due to their efficiency, but we need to reduce the presence of motorised transport and increase green spaces.
Tamara Iungman and Sasha Khomenko, ISGlobal researchers and co-lead authors of the study, state that according to these results, the compact city continues to be the model of the future for cities, due to its efficiency. However, it would be necessary to work on their urban planning to reduce the presence of motorised transport and increase green spaces – for example, with the superblocks, or by planting more trees. “This would reduce mortality rates significantly,” they say.
You can see the ranking of your favorite city in terms of pollution, green spaces and road traffic noise in isglobalranking.org.
Iungman T, Khomenko S, Pereira Barboza E, Cirach M, Gonçalves K, Petrone P, Erbertseder T, Taubenböck H, Chakraborty T, Mark Nieuwenhuijsen M. The impact of urban configuration types on urban heat islands, air pollution, CO2 emissions and mortality in Europe: a data science approach. The Lancet Planetary Health , 2024. 8: e489–505. https://doi.org/10.1016/S2542-5196(24)00120-7
