- The role of urban trees in reducing land surface temperatures in European cities. Areas in European cities with trees are approximately 2–4 times cooler than urban green spaces without trees, according to a study published in Nature Communications. https://www.nature.com/articles/s41467-021-26768-w?utm_source=twitter&utm_medium=social&utm_content=organic&utm_campaign=NGMT_USG_JC01_GL_NRJournals 9 comments science