SkyscraperPage Forum - View Single Post - Cities are vulnerable to heatwaves. But green spaces can help more than we thought

hauntedheadnc · #1 Posted **Mar 5, 2024, 10:29 AM**

Cities are vulnerable to heatwaves. But green spaces can help more than we thought
ZME Science

Quote:

It’s not just that the planet is getting hotter; cities are getting much hotter than their surroundings. In fact, urban heatwaves have become a common occurrence, affecting 1.7 billion people. In Europe alone, the 2023 heatwave killed over 61,000 people. Now, a new study by researchers in the UK shows how much green interventions can help cool down cities.

***

The cooling effect of green infrastructure varies depending on multiple factors (including local climate, the species involved, etc). But the effect is pronounced. Botanical gardens are, on average, a whopping 5 degrees Celsius cooler than their surroundings. Even a street tree cools its immediate surroundings by almost 4 degrees. This is how much different types of green infrastructure can reduce local temperatures:

Quote:

Botanical gardens: -5 °C avg (variation: -2.2 to -10 °C)
Wetlands: -4.7 °C avg (variation: -1.2 to -12 °C)
Rain garden: -4.5 °C avg (variation: -1.3 to -7 °C)
Green walls: -4.1 °C avg (variation: -0.1 to -18 °C)
Street trees: -3.8 °C avg (variation: -0.5 to -12 °C)
City farm: -3.5 °C avg (variation -3 to -3.9 °C)
Parks: -3.2 °C avg (variation -0.8 to -10 °C)
Reservoirs -2.9 °C avg (variation -1.8 to 5 °C)
Playgrounds: -2.9 °C avg (variation: -2.8 to -3 °C)

In general, the team found that the bigger the park (or any other green infrastructure), the bigger the benefits. Furthermore, if parks are linked together via green corridors, there’s also a compound effect.