Understanding policy and technology responses in mitigating urban heat islands: A literature review and directions for future research

Policy and technology responses to increased temperatures in urban heat islands (UHIs) are discussed in a variety of research; however, their interaction is overlooked and understudied. This is an important oversight because policy and technology are often developed in isolation of each other and not in conjunction. Therefore, they have limited synergistic effects when aimed at solving global issues. To examine this aspect, we conducted a systematic literature review and synthesised 97 articles to create a conceptual structuring of the topic. We identified the following categories: (a) evidence base for policymaking including timescale analysis, effective policymaking instruments as well as decision support and scenario planning; (b) policy responses including landscape and urban form, green and blue area ratio, albedo enhancement policies, transport modal split as well as public health and participation; (c) passive technologies including green building envelopes and development of cool surfaces; and (d) active technologies including sustainable transport as well as energy consumption, heating, ventilation and air conditioning, and waste heat. Based on the findings, we present a framework to guide future research in analysing UHI policy and technology responses more effectively in conjunction with each other.