Identification and cooling effect analysis of urban ventilation corridors in coastal hilly cities: A case study of Shenzhen

Urban ventilation corridors (UVCs) play a key role in promoting cold air circulation and mitigating the urban heat island effect. This study explores methods to identify UVCs in coastal hilly cities and assess their cooling effects, using Shenzhen as a case study. Based on prevailing wind direction variations, the study area was divided into 14 local ventilation zones. The inverse of the current values derived from the circuit-based approach was classified into 5 levels and used as cost parameters in the least-cost path analysis to identify UVCs. Their cooling effects were evaluated by comparing land surface temperature differences between corridors and surrounding areas. The results show that: (1) The circuit-based current exhibits a stronger correlation with CFD-simulated wind speed (R = 0.756) compared to frontal area density (R = −0.530); (2) UVC cooling effects vary by corridor type and diurnal cycle; (3) during the day, distance from the coastline and mountains enhances cooling in some UVC types, while at night, the opposite trend is observed. This study establishes a framework for UVC identification in coastal hilly cities and deepens understanding of their cooling mechanisms, providing scientific support for urban climate planning.