Heat, growth, and space : a geospatial analysis of land use development and thermal change in Malta

Abstract

Urban Heat Island (UHI) has become an increasingly important environmental challenge as urbanization intensifies, leading to elevated surface temperatures that affect public health, energy consumption, and environmental sustainability. This study investigates the spatial and temporal evolution of land surface temperature (LST) across Malta between 1985 and 2025 and examines the relationship between land use change and the urban heat island effect. Landsat imagery was processed using Google Earth Engine and ArcGIS products to derive LST datasets, while supervised land cover classifications were used to quantify changes in urban, vegetative, and barren land. Annual averages of monthly median and maximum temperatures were analyzed for individual local councils using zonal statistics and time-series analysis. Results indicate that highly urbanized councils, including Birkirkara, Hamrun, Santa Venera, and Luqa, consistently recorded higher LST than less urbanized councils such as Fontana, Ghasri, and Rabat (Gozo). While regional climate variability produced synchronized warm and cool periods across the islands, urban areas exhibited greater thermal intensity and more pronounced temperature extremes, particularly during warming events in the early 2000’s and mid 2000’s. The findings demonstrate a strong relationship between urban development and elevated LST, confirming the persistence of the urban heat island effect across Malta over the past four decades. This research provides a long-term assessment since Landsat images have become available to assess urban thermal patterns and identify vulnerable regions, and offers evidence to support sustainable planning strategies, including increased vegetation cover and green infrastructure to mitigate future heat-related impacts.