How greenness is defining cities
As cities become bigger and denser, green spaces are boosting their resilience and making them more attractive places to live
Cities are placing increasing emphasis on green spaces in a bid to tackle environmental challenges, improve quality of life and prepare for future growth.
From pledging more outdoor space to planting trees, efforts to improve biodiversity and reduce pollution are underway. These aim to make cities more resilient to ever more frequent adverse weather events and alleviate concerns such as plummeting air quality that affects over 90 percent of the global population.
“Green infrastructure initiatives are essential catalysts for creating more sustainable and resilient cities,” says Jeremy Kelly, Lead Director, Global Cities Research at JLL. “City governments are increasingly aware of the need to take action as the impact of a changing climate becomes ever more evident.”
Turning to green infrastructure
Installing green infrastructure – strategically placed networks of features including green spaces, vegetation on buildings and sustainable drainage systems - is now becoming widespread.
“With the threat of climate change, city governments are placing more emphasis on green infrastructure that can help to reduce pollution and mitigate climate-related risks such as flooding,” says Jessica Herman, senior sustainability advisor at JLL.
China, for example, is aiming to counter changing weather patterns by replacing concrete pavements with wetlands and gardens to capture increased rainwater and reduce its flood risk. The government has spent more than US$12 billion on the “sponge cities” program since 2014.
With many cities now grappling with more extreme heatwaves, tree-planting is becoming a way to cool urban centres and reduce heat islands, where roads and buildings soak up and radiate heat to increase already high temperatures.
Melbourne plans to double its tree cover by 2040. Miami’s Chief Heat Officer recently spoke of plans to increase the city’s tree canopy from under 20 percent to 30 percent in the next 10 years. Paris is planning to plant 170,000 trees by 2026.
Greener spaces have significant benefits for humans, too. It can make urban centres more visibly attractive, provide cleaner air, and have a better overall impact on physical and mental health.
“City governments are having to focus much more on liveability and sustainability to not only satisfy residents, but to attract and retain talent and businesses,” says Kelly. “People want to be able to relax outdoors in a smog-free environment or cycle to work through parks instead of congested roads.”
Ambitious proposals are needed to re-introduce nature into cities. London, which was named the world’s first National Park City in 2019, has plans to make more than half of the city green by 2050 in addition to planting more trees and investing in large-scale green development projects. Meanwhile, the Ultra Low Emissions Zone aims to lower pollution in the city centre.
Building a net zero future
Such investments in creating green spaces can also help cities meet broader sustainability goals such as reaching net-zero carbon emissions.
London is one of 19 cities to have pledged that all new buildings will be net-zero by 2030, while eight European cities including Madrid and Wroclaw are part of a EU-funded scheme to decarbonise all buildings by 2050.
“City governments are taking the lead when it comes to climate mitigation measures, and they are often considerably more ambitious in their targets and actions than some national governments,” says Kelly.
The challenge is that reaching net-zero and green targets will require radical changes to urban operations.
“Net-zero targets will significantly impact city design, from how buildings are built to how we use resources,” says Herman. This could not only be costly - for the UK, reaching net-zero is estimated to cost up to £70 billion a year – but also come at the expense of other civic infrastructure.
With nearly 70 percent of the world’s population predicted to be living in cities by 2050, overcoming these hurdles will be increasingly crucial.
“The measure of a city’s success is now based on many sustainability criteria, including biodiversity,” Kelly says.
“We will continue to see migration to urban centres and there’s a real challenge as to how these cities can not only absorb further growth but reduce their environmental impact. In the face of urbanization, green infrastructure isn’t about beautifying cities; it’s about future-proofing them.”