Investigating the urban heat island effect: Impacts of diverse urban morphologies in semi-arid Marrakesh

The Urban Heat Island (UHI) effect presents significant challenges to urban environments, leading to increased energy consumption, deteriorating air quality, and elevated health risks. This study provides a pioneering sensitivity analysis of the Urban Weather Generator (UWG) model—the first of its kind to comprehensively assess the impact of both irregular and traditional urban forms in a semi-arid Mediterranean context. Marking one of the most extensive simulations conducted in this region, our research investigates the complex interactions between urban morphology, including modern, traditional, and irregular configurations, and their impact on local air temperatures. We conduct an extensive solar exposure analysis, quantifying incident solar radiation (kWh/m²) and performing sky view simulations across various urban zones. Our findings reveal striking thermal differentials, with variations reaching 5 °C daily and 3.5 °C annually, closely tied to urban density and configuration. Additionally, we explore the interplay between UHI and Urban Cool Island (UCI) effects, uncovering untapped potential for urban design optimization to effectively mitigate thermal impacts. By addressing critical gaps in urban morphological data and incorporating irregular forms into the analysis, our innovative approach lays the groundwork for a paradigm shift in urban planning. This comprehensive study not only enhances the understanding of UHI dynamics in semi-arid climates but also provides valuable insights for developing sustainable, resilient urban environments.