Optimal allocation of local climate zones based on heat vulnerability perspective

Abstract

Global climate change presents considerable heating risks to cities, necessitating the assessment of heat vulnerability characteristics in urban areas for the advancement of human settlements and socioeconomic progress. Nevertheless, there has been a lack of extensive research regarding heat vulnerability when considering local climate zones (LCZs). In this study, we utilized data from multiple sources to construct a model for evaluating heat vulnerability along three dimensions: Exposure, Sensitivity, and Adaptability. We analyzed the spatial characteristics of heat vulnerability in the LCZs and employed a linear weighted multi-objective optimization method to reconfigure the LCZs and mitigate the Urban Heat Vulnerability Index (HVI). The findings revealed that (1) The spatial characteristics of exposure and sensitivity were similar, with high values observed in the city center and low values at the periphery. Adaptability exhibited a high–low–high pattern from the center to the edge due to the combined influence of the economy and natural factors. (2) The HVI of the built environment (building LCZ) surpassed that of the natural environment (natural LCZ) within the research area. Specifically, compact high-rise buildings (LCZ1) and compact midrise buildings (LCZ2) accounted for over 90% of the area with extremely high and high HVI values, necessitating immediate optimization efforts. (3) By considering the area and population size of the research area, we achieved an optimal heat vulnerability plan by increasing the areas of LCZ4 and LCZA while reducing the areas of LCZ8 and LCZ1, among others. Therefore, the overall HVI of the study area decreased from 49,034.67 to 41,772.37, representing a reduction of 14.81 %. This study presents an innovative approach to mitigating urban heat vulnerability, providing valuable planning references and scientific guidance to assist cities in addressing high-temperature risks.