Trees cool European cities by up to 12 degrees – What new research shows

Areas of European cities that have trees are about two to four times cooler than areas of urban greenery without trees, according to a new European scientific study. The research highlights the difference between green spaces depending on whether they include trees or not, as if they exist, the temperature tends to be significantly lower, up to 12 degrees in some areas in summer.

Previous research has shown that trees can mitigate the heat of cities, which also has a positive effect on human health. Trees reduce urban temperatures both through the shade they provide and through the process of perspiration (expulsion of water in the form of water vapor). On the other hand, the green without trees seems to drop the temperatures much less or not at all, while in some cases of cities green areas without trees were found to have even higher temperatures in relation to the surrounding urban space.

Researchers from Switzerland, led by Jonas Swaab of the Swiss Federal Institute of Technology (ETI) in Zurich, who published the journal Nature Communications, analyzed data from 293 European cities (including Athens and others). five Greek cities), comparing temperature differences between urban areas with trees and green areas without trees, using both satellite and terrestrial data.

The analysis concluded that areas with trees have temperatures two to four times lower than those without trees. The difference is more noticeable in central Europe (temperature reduction by 8 to 12 degrees Celsius thanks to the trees) than in southern Europe (reduction by up to four degrees). In the warmer climates of southern Europe both the soil and the vegetation are drier, with the result that the refreshing effect of perspiration is less than in the northern climates.

Scientists have stressed the need to plant more trees in European cities as temperatures rise due to climate change.