After a landslide in 2017 killed 1,141 people and left more than 3,000 homeless in Sierra Leone’s capital Freetown, the city’s recovery plan had included training residents to plant 21,000 native trees, to reduce the risk of future disasters on bare hillsides.
Amid erratic and unusually heavy rains, as well as urban expansion, the city’s mayor had ran a “Freetown the Treetown” campaign, to increase green cover by 50 per cent before the end of 2022. Locals were told to help track tree growth via a smartphone app.
Meanwhile, in South Korea, the Seoul city government, also worked with residents to restore a river that had been covered by a highway overpass. The nature revival project for the Cheonggyecheon Stream, carried out since the early 2000s, has lowered traffic, flooding and temperatures, as well as stimulated nearly $2 billion in urban redevelopment, while attracting 64,000 visitors a day.
Examples like these suggest that cities should invest more in expanding green spaces and nurturing natural systems that provide water, food and clean air — not just to keep residents healthy and tackle climate-change risks, but to boost their economies, said researchers in a report released by the BiodiverCities by 2030 initiative on Monday.
Despite the benefits of green urban improvements, little money is currently spent on these initiatives, they said. The BiodiverCities by 2030 initiative is led by the World Economic Forum (WEF), the Alexander von Humboldt Biological Resources Research Institute in Bogota, and the Colombian government.
According to the report, cities had invested no more than 0.3 per cent of their infrastructure spending, or only about $28 billion on “nature-based solutions”, usually defined as actions to protect, sustainably manage and restore natural or modified ecosystems, in 2021. The researchers called for more investments in this aspect.
GDP at risk
Akanksha Khatri, WEF’s head of nature and biodiversity, said the conventional view that urban development and a healthy environment are at odds no longer holds.
“Nature can be the backbone of urban development,” she said in a statement. “By recognising cities as living systems, we can support conditions for the health of people, planet and economy in urban areas.”
The report warned that if cities fail to protect their natural habitats, 44 per cent of their gross domestic product — or $31 trillion globally — is at risk.
That could be from floods - identified as the most common natural risk across more than 1,600 cities with over 300,000 inhabitants — due to problems such as loss of coastal mangroves that keep storm surges at bay or waste-clogged rivers, it said.
Other major threats from climate and nature damage include drought — with one in four cities already water-stressed — fiercer heatwaves, and water and air pollution which take a toll on human health.
The resulting economic losses could be averted by investing a larger slice of stretched municipal budgets in “green infrastructure” like parks, street trees, lakes, wetland areas and roofs with gardens.
Spending $583 billion a year by 2030 on such solutions and projects that free up city land for nature could create more than 59 million jobs, including 21 million dedicated to restoring and protecting natural ecosystems, the report noted.
Nature-based solutions are on average 50 per cent more cost-effective than man-made, concrete-heavy options such as roads, buildings and paved areas, it found.
Breaking down barriers
Robert McDonald, a scientist with The Nature Conservancy and a member of the BiodiverCities global commission, said that just doubling spending on green infrastructure — which would still account for only a tiny share of municipal projects — would be “transformative for how a lot of cities feel to live in”.
Yet the traditional option of building concrete infrastructure still tends to win, partly due to silos between city departments, he told the Thomson Reuters Foundation.
Reaping the full benefits of expanding urban nature will require working across municipal governments, as well as with companies and citizens, he added.
The advantages of nature-based solutions, like planting trees to shade and cool streets, are starting to become evident as climate change bites in the form of threats such as worsening heatwaves that hit city dwellers hardest, McDonald noted.
That is driving broader recognition of the value of investing in nature, he said.
“Even folks who really want to think about dollars and cents are realising that link,” he said.
This story was published with permission from Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, climate change, resilience, women’s rights, trafficking and property rights. Visit http://news.trust.org/climate.
