What’s going on here?
Having more trees in cities could have prevented over a million heat-related deaths globally since the year 2000. That’s according to new research published in the Lancet, which modelled the cooling effects of trees and green space in urban areas.
What does this mean?
Trees, parks and green spaces all help to keep towns and cities cool during the summer by providing shade and preventing the ‘urban heat island’ effect. This is a well-known phenomenon, but this study has modelled the effect on human health for the first time.
Researchers modelled the effects of heat between 2000 and 2019 and found that if cities had had 30% more vegetation during this period, they would have been 0.19C cooler on average.
That might not sound like much, but this cooling effect could have prevented over a third of heat-related deaths worldwide, saving the lives of 1.16 million people.
Why should we care?
As global temperatures rise, extreme heat is putting our health at risk.
Heat can exacerbate underlying health conditions such as cardiovascular disease, diabetes and asthma. There have been almost half a million heat-related deaths each year since 2000. In the UK alone, 1 in 5 people have suffered from ill health due to heatwaves.
This study shows that increasing the ‘greenness’ of our cities could be a simple but powerful way to protect urban populations from extreme heat.
Be curious
- From the Curious archives: Rooting for greener cities: How trees help to protect us from disease
- Curious about the urban heat island effect? Watch this explainer video
