Quantifying the effect of green-roof and urban green infrastructure ratio on urban heat island mitigation -semi-arid climate

Green Roof (GR) is one of the most applied strategies to Mitigate Urban Heat Island (UHI) recommended for sustainable cities. This research aims to examine and evaluate the effect of the GR/UGI ratio on UHI mitigation, creating Urban Cool Island (UCI). The study was carried out at Constantine, situated in the East part of Algeria, characterized by a semi-arid climate with high summer solar radiation intensity. An urban climate analysis was conducted during the hottest period of the year by means of remote sensing data using ArcGIS 10.2 platform. The results displayed that vegetation, urban density, and topography strongly affect UHI. Furthermore, other finding results in this research show that fixing GR/UGI ratio (with 0.0063 reduced the average air temperature by 1.24°C) in a large-scale urban area, can reduce the surface temperature by 4.00 degrees of the studied area.