Investigating the relationship between the Urban Heat Island Effect and its influencing factors: A case study of Perth

Abstract. Rapid urbanisation significantly alters land surface characteristics and increases heat-related risks, such as the Urban Heat Island (UHI) effect. Urban growth and the resulting UHI elevate surface temperatures in urban environments, exacerbating environmental challenges such as biodiversity loss and poor urban air quality, while also posing risks to human health, including heat-related illnesses and increased vulnerability among susceptible populations. This study investigates the correlation between urban development and summer daytime Land Surface Temperature (LST) in the Perth Metropolitan Region (PMR). Using multi-temporal Land Use Land Cover (LULC) data and factors influencing LST, the spatial patterns of urban growth and their thermal characteristics were analysed. The results of this study showed that newer developments experience higher surface temperatures than older neighbourhoods due to higher impervious surfaces and limited vegetation cover. Statistical analysis was quantified using the Ordinary Least Squares (OLS) regression model, which identified tree canopy cover, surface moisture, building density and population density as the most influential predictors of LST. Surface moisture and tree canopy cover showed a negative correlation, whereas building and population density showed a positive relationship with LST, particularly in the newer neighbourhoods. The findings from this study underscore the vital need to integrate urban planning strategies to enhance urban green infrastructure and to incorporate climate-resilient designs in newer developments to combat rising LST and the associated public health and environmental impacts in rapidly evolving cities like Perth.