Surface Urban Heat Island Variability in Cosenza, Southern Italy: The Roles of Urban Morphology, Extreme-Temperature Conditions, and Local Wind Conditions

Abstract

Mediterranean cities with complex terrain are increasingly exposed to overheating. This study investigates Surface Urban Heat Island Intensity (SUHII) in Cosenza, southern Italy, in relation to land-use, neighborhood-scale morphology, extreme-temperature conditions and local wind. Summer ECOSTRESS Land Surface Temperature (LST) observations from 2018 to 2025 were integrated with CORINE Land Cover, CLC+ Backbone, urban morphological indicators, and meteorological data. Continuous urban fabric exhibited the strongest SUHII, with median values reaching about 6.5 °C at midday, whereas less compact urban areas exhibited lower thermal contrasts. A bin-based analysis revealed clear within-class morphological gradients, particularly in discontinuous urban fabric and industrial/commercial areas, where increasing building height, building surface fraction, and impervious surface fraction were generally associated with higher SUHII; these relationships were weaker and less systematic in compact urban fabric. TX90p conditions were associated with lower SUHII than No-TX90p conditions, likely reflecting stronger warming of rural reference surfaces and a reduced urban–rural thermal gradient. Wind-related differences were generally modest and non-systematic across land-use classes, TX90p categories, and diurnal periods. Overall, SUHII variability reflects both categorical land-use differences and continuous neighborhood-scale morphological gradients, while extreme-temperature and ventilation conditions further modulate urban–rural surface thermal contrasts in this Mediterranean valley city under complex topographic conditions.