Planting more trees could reduce deaths caused by high summer temperatures in cities by a third, according to a study released by The Lancet.A research team from Barcelona found that of the 6,700 premature deaths at European cities in 2015, a third of these (2,644) could have been prevented if urban trees had been increased by 30%.
The shade of trees as a protection factor
Their study also found that the shade provided by trees reduced urban temperatures by an average of 0.4 degrees during the summer.”We already know that high temperatures in urban settings are associated with negative health outcomes, such as cardiorespiratory failure, hospital admissions, and premature death,” said study lead author Tamara Lungman, from the Barcelona Institute for Global Health.
Strategically integrating green infrastructures
The objective of the research, said the expert, is “to inform the authorities about the benefits of strategically integrating green infrastructures into urban planning in order to promote more sustainable and resilient urban environments and contribute to the adaptation and mitigation of climate change“.
Heat mortality in summer
To reach these conclusions, the researchers estimated the death rates of residents aged 20 and over in 93 European cities between June and August 2015, some 57 million inhabitants in total.
After analyzing the data, based on two different study models, they concluded that 6,700 premature deaths could be attributed to hotter urban temperatures during the summer months, 4.3% of summer mortality and 1.8% of mortality annual.
According to the study, this corresponds to 39.5% of all deaths attributed to warmer urban temperatures, 1.8% of all summer deaths, and 0.4% of annual deaths.
“Our results suggest that there are large impacts on mortality due to warmer temperatures in cities, and that these impacts could be partially reduced by increasing the cover provided by trees to help cool urban environments,” says the co-author. Mark Nieuwenhuijsen, Director of Urban Planning, Environment and Health at the Barcelona Institute for Global Health.