Understanding and measuring the cooling performance of trees

Abstract

Trees and the urban forest are essential cooling devices for adapting cities to urban heat. This chapter explores the potential of these solutions to adapt to climate change while addressing essential considerations and challenges within the urban design domain. Thermal mechanisms through which trees contribute to cooling urban environments are presented, ranging from shade provision and evapotranspiration at the scale of the tree to the scale of a tree ensemble, area, and urban forest network. Principles for careful green space planning and strategically placing trees are introduced with a specific focus on the spatial factors that optimize their cooling effects and maximize their benefits. Additionally, this chapter highlights the value of onsite measurements in assessing the magnitude of trees’ cooling potential. Data collection methods are introduced to evaluate the impact of trees and other nature-based interventions on temperature, humidity, and wind patterns. Finally, this chapter discusses the complex nature of urban environments, related limitations and opportunities for enlarging, maintaining and integrating green areas into densely built areas.