The role of urban trees in reducing land surface temperatures in European cities

Urban trees influence temperatures in cities, yet their effectiveness at mitigating urban heat across climates and relative to treeless urban green spaces remains insufficiently explored. Using high-resolution satellite land surface temperatures (LSTs) and land-cover data from 293 European cities, the study infers the potential of urban trees to reduce LSTs. Urban trees exhibit lower temperatures than urban fabric in most European cities in summer and during hot extremes. Compared to continuous urban fabric, LSTs over urban trees are on average 0–4 K lower in Southern European regions and 8–12 K lower in Central Europe. Treeless urban green spaces are less effective, with cooling approximately 2–4 times lower than that induced by urban trees. By revealing continental-scale patterns in the effects of trees versus treeless green spaces on urban LST, results highlight the importance of considering climate-dependent effectiveness of heat mitigation measures in cities.

Jonas Schwaab, Ronny Meier, Gianluca Mussetti, Sonia Seneviratne, Christine Bürgi, Edouard L. Davin