CLIMATE RESILIENCE
URBAN OASES EMERGE FROM CONCRETE JUNGLES
MEDELLÍN, COLOMBIA
Photo: Steffen Schmitz / Wikimedia commons
Greenery offers more than just beauty to a city. The green corridors in Medellín, Colombia, linking parks and vertical gardens were installed to cool and scrub the air to improve life for residents and visitors. The city’s results are persuasive arguments for adding green spaces to concrete places everywhere.
What's
changing
Urban zones can be up to 4 degrees Celsius (7 degrees Fahrenheit) hotter than areas with greenery. City sidewalks, roads and towering buildings constructed from manmade materials absorb and reflect more heat than vegetation, which cools the environment. As global temperatures rise, urban heat islands make cities unbearably hot.
What's already
possible
Medellín, Colombia invested $16.3 million US dollars into creating green corridors throughout the city, engaging experts and enthusiastic citizens to install plants in specific locations to cool the city and improve overall air quality. These plantings have reduced the urban heat island effect, bringing temperatures in line with Medellín’s nickname: City of Eternal Spring.
Seizing
the opportunity
Medellín, Colombia's second-largest city, launched its green corridors program in 2016 to combat air pollution and rising temperatures. The initiative created 30 green corridors that connect more than 124 parks and use carefully selected plants that mimic natural forest landscapes, enhancing urban vegetation and biodiversity. Plants, including mango trees, palms and bamboo, are selected for hardiness and longevity. These corridors serve as green barriers, absorbing pollution and improving air quality. To encourage new ecofriendly habits in residents, the city installed bicycle paths in the green spaces, leading to a 34.6% increase in cycling throughout Medellín. Now that the building phase of the project has ended, volunteer gardeners from within the community plant and maintain the green spaces.
Standout
tactic
The green corridors project created more than 500 jobs and established a training program to help vulnerable people displaced by violence in Colombia secure permanent positions as gardeners in Medellín.
How
it helps
Medellín's temperatures dropped by 2 degrees Celsius (3.6 degrees Fahrenheit) within the first three years of the green corridors program. A further decrease of 4 degrees to 5 degrees Celsius (7 degrees to 9 degrees Fahrenheit) is expected over the next few decades, even factoring in climate change. Air quality improved enough to lower the city's rate of acute respiratory infections by 40% between 2016 to 2019.
Diving
deeper
What can cities do to ensure enough funding is available every year to keep green corridors thriving once the initial enthusiasm for this kind of project might have faded? How can they plan for potentially devastating plant pests or diseases?
Increasing
impact
Medellín’s success in reversing its heat island effect could be a blueprint for other cities facing a loss of greenery. By sharing its resources and strategies, Medellín can help cities adapt the green corridors initiative to different climates, geographies and community needs.
Traveling
better
Travel is inherently carbon intensive. Whether you are taking a mini-break or an annual vacation, consider ways to minimize your impact by staying longer in one place, reconsidering how you travel to the destination, and supporting businesses that are working to make their community and the world a better place.
