Streetscape design for improving outdoor thermal comfort in urban public space: a case study of a subtropical city

The natural systems approach used by green streets can cope with climate change and provide an improved thermal environment. With an emphasis on summer conditions in the subtropical cities of Shenzhen, this study considers the correlation between urban microclimate and street design. The purpose of this study is to provide different green strategies for improving thermal comfort in the street. These design strategies could be applied to the whole city to provide valuable insight into improving streetscapes' thermal environments. The methods used in this study comprise landscape design and environmental simulation, which are capable of proposing a visionary future plan for the streetscape. The landscape design method includes three scenarios with revised design interventions. The three scenarios are: 1. green walls and improve in material albedo for pavements; 2. add trees and grass on the ground level; 3. combining scenario 1 and scenario 2. Environmental simulations are used to evaluate the effectiveness of different design scenarios. The results show that: 1 Reducing urban heat and improving outdoor thermal comfort can be achieved by increasing urban vegetation; 2. Adding trees are more effective than vertical greening in alleviating outdoor thermal comfort.