Elgendy Donia, Tolba Osama, Kamel Tarek
Arab Academy for Science, Technology and Maritime Transport - Heliopolis, Cairo, Egypt.
Sci Rep. 2025 Jul 11;15(1):25165. doi: 10.1038/s41598-025-08574-2.
This study investigates the influence of increasing road surface albedo on outdoor air and surface temperatures in residential areas, taking into account constraints on broader environmental modifications. Urban albedo, which is determined by spatial geometry and material reflectance, influences the amount of solar radiation bouncing back into the atmosphere. Field measurements were conducted on-site to document Air Temperature (T), Wind Speed (WS), Relative Humidity (RH), Mean Radiant Temperature (MRT) providing the basis for validating simulation models. The urban geometry was reconstructed from real site data and simulated using a hybrid modeling approach, combining Ladybug with Grasshopper for Surface Temperature (T), MRT, and Universal Thermal Climate Index simulations, and ENVI-met for T, RH, and WS simulations. ENVI-met outputs were integrated into Grasshopper to achieve high-accuracy environmental modeling. Results demonstrate that increasing pavement albedo from 0.12 to 0.50 reduced T by up to 12.94 °C at peak solar hours and lowered T by a maximum of 1.96 °C during the day. The research addresses a critical gap by focusing solely on altering material reflectivity without changing urban morphology or adding any canopies either structured or vegetation. The findings confirm that enhancing surface albedo is an effective method to reduce daytime heat trapping & accumulation, and shortwave radiation absorption which mitigate the Urban Heat Island phenomenon.
本研究调查了提高路面反照率对居民区室外空气温度和地表温度的影响,并考虑了更广泛环境改造的限制因素。城市反照率由空间几何形状和材料反射率决定,它会影响反射回大气中的太阳辐射量。进行了现场实地测量,记录气温(T)、风速(WS)、相对湿度(RH)和平均辐射温度(MRT),为验证模拟模型提供依据。根据实际场地数据重建城市几何形状,并采用混合建模方法进行模拟,将Ladybug与Grasshopper结合用于地表温度(T)、MRT和通用热气候指数模拟,将ENVI-met用于T、RH和WS模拟。将ENVI-met的输出结果集成到Grasshopper中,以实现高精度的环境建模。结果表明,将路面反照率从0.12提高到0.50,在太阳辐射峰值时段可使气温降低多达12.94°C,白天最高可降低1.96°C。该研究通过仅专注于改变材料反射率,而不改变城市形态或添加任何结构化或植被的树冠层,填补了一个关键空白。研究结果证实,提高地表反照率是减少白天热量捕获和积累以及短波辐射吸收的有效方法,可缓解城市热岛现象。