Modeling Urban Heat Island Mitigation Strategies in Egyptian Cities Using ENVI-met

Mitigation techniques for urban heat islands (UHI) have emerged as a critical concern for global urban environmental sustainability. Passive cooling employing cool materials and/or urban greening has shown to be the most effective strategy for mitigating the impacts of UHI. This latter method, however, is relatively new in the literature of urban environmental studies, and research on it is still limited, particularly for cities in hot-dry climatic zones. This study aims to investigate the possibility of improving albedo rates and adopting urban greening measures, such as greening building roofs, roadways, and walkways, in several Egyptian cities located in various climatic areas. The comprehensive climate model ENVI-met was used to predict the possible temperature drop in the streets on a hot summer day of three areas within three different regions in Egypt. New Damietta was chosen from Mediterranean region, Cairo was picked as a semi-desert region, and Qena city in upper Egypt was selected as a desert city. The paper concludes that temperature decreased in all studied areas, and there was convergence in the level of temperature reduction between cities. The Mediterranean region, represented by the urban complex of New Damietta, has a significant temperature reduction of 2.89°C. In the semi-desert region, Cairo's urban complex had a temperature differential of 2.3°C. Whereas Qena had a temperature difference of 1.24°C. Thus, Qena recorded the smallest temperature differential because of the city's harsh climate during the summer months. Nonetheless, the adopted mitigation method propels to thermal mitigation in urban syntax.