Evaluating District Indicators for Mitigating Urban Heat Island Effects and Enhancing Energy Savings

Abstract

As climate change accelerates and urbanization intensifies, mitigating the Urban Heat Island (UHI) effect has become crucial for sustainable urban planning. This study evaluated the role of four key urban indicators—buildings, greenery, streets, and pedestrian paths—in reducing air temperature and improving energy efficiency within the Kartal District of Istanbul. To ensure accurate and data-driven results, multiple advanced software tools were integrated throughout the research process. QGIS, Google Earth, and OpenStreetMap were used to generate high-resolution land use/land cover (LULC) maps, while Meteoblue climate data and the Global Heat Island Map provided essential climatic parameters. The InVEST Urban Cooling Model was employed to simulate temperature reduction effects, and eQuest energy simulation software assessed the impact of building modifications on energy consumption. The study tested multiple UHI mitigation scenarios, including green roofs, increased street tree cover, grass-covered pedestrian paths, and high-albedo pavement, comparing their individual and combined effects. The results indicated that integrating all strategies achieved the most significant cooling impact, reducing air temperatures by 1.14 °C and improving energy efficiency by 61%. Among the individual interventions, green roofs provided the highest building energy savings (28% reduction), while grass-covered pedestrian paths homogenized the district-wide temperature distribution. These findings underscore the importance of combining GIS-based spatial analysis, climate modeling, and energy simulation tools to develop reliable, scalable, and effective urban heat mitigation strategies. Future urban planning should prioritize a multi-software approach to enhance sustainability, optimize energy efficiency, and improve urban resilience.