Efficient and cost-effective method for identifying urban ventilation corridors using a heuristic search algorithm

Abstract

Global temperatures are rapidly increasing, and one of the consequences of such increases is the urban heat island effect, which is a major problem. Enhancing urban ventilation is a key strategy for reducing urban temperatures. This study proposes a method for efficiently identifying urban ventilation corridors. Taichung City in central Taiwan was selected as the study area, and remote sensing technologies were used to observe and extract the urban building information in two sites. The collected information was used to develop maps of the roughness length (z0) in the city, and a heuristic search algorithm (A* search algorithm) was used to identify the urban ventilation corridors in the two sites and Taichung City overall. The results revealed that the remote sensing technologies were both accurate and cost-effective in obtaining building information, and the identified ventilation corridors were also accurate and exhibited higher-than-average wind speeds. Hence, the proposed method can be used to inexpensively and conveniently identify both corridors with high ventilation potential and poor ventilation that require urgent improvement. The method was further applied to identify ventilation corridors in the entirety of Taichung City, demonstrating the suitability of the proposed method for larger-scale applications.