Spatio-temporal pattern of heat island in Shenzhen and its influencing factors

School of Architecture and Built Environment, The University of Newcastle, Newcastle, Australia.

Abstract

In recent years, with the rapid expansion of global urbanization, large-scale human activities have changed the surface characteristics, which has significantly enhanced the urban heat island effect. Heat islands may lead to heatstroke, increasing health problems, deteriorative air quality, expanding energy consumption, and more water resource pressure, which reduces life quality and leaves a negative impact on the health, environment, and life of urban residents. Based on the monthly surface temperature in Shenzhen in 2022, this study judges the temporal distribution characteristics of the heat island effect and selects July as the representative month to retrieve the spatial distribution characteristics of the heat island effect. In addition, multi-scale geographically weighted regression (MGWR) is used to conduct regression modeling on various influencing factors, so as to identify the leading factors affecting urban heat island effect. The results are as follows: (1) From the temporal perspective, there are obvious seasonal differences in the heat island effect in Shenzhen with a gradual dispersion and gentle evolution pattern from summer to winter, while other seasons show uniform performance without apparent change. (2) From the spatial perspective, the heat island effect in Shenzhen presents an “N” pattern featuring “low, high, low, and high” from the center to the outside. (3) The main factor that positively affects the urban heat island effect in Shenzhen is the night light intensity as the urban development index, while the main factor with negative impacts is the vegetation index as the natural index. This study aims to reveal the main influencing factors of the heat island effect in Shenzhen by analyzing its spatio-temporal pattern, so as to foster a deeper understanding of the spatio-temporal characteristics of the heat island effect and provide useful reference for urban managers and planners. Thus, the micro-transformation of the built environment can be implemented to reshape the urban heat island pattern and reduce the losses suffered by cities during the heat wave disaster. It is hoped that the results of this study can offer theoretical insights for future urban planning and heat wave disaster prevention in Shenzhen.