Evaluating the natural cooling potential of waterbodies in dense urban landscape: A case study of Bengaluru, India

This study examines the water-induced cooling capability of 12 waterbodies in Bengaluru City, India, using Landsat 8 OLI/TIRS data. The study categorized and investigated the cooling impact of urban landscapes using Local Climatic Zone (LCZ) classification. The results indicate that dense urban built-up areas and impervious surfaces lead to higher Land Surface Temperature (LST). Large-sized waterbodies surrounded by a higher fraction of built-up LCZs moderate the temperature, while small waterbodies are less capable of thermal cooling. The Water Cooling Range (WCR) during the summer season varies from 120 m to 330 m, with Water Cooling Intensity (WCI) ranging from 1.29 °C to 2.71 °C. However, WCI drastically reduces in the winter season, ranging from 0.63 °C to 1.8 °C. The maximum Water Cooling Gradient (WCG) was found to be 0.017 °C/m in the summer season. The study found that LCZ composition affects the cooling potential of waterbodies, reducing temperature by up to 2 °C. These findings indicate that water-induced cooling is a viable technique for heat mitigation, particularly in densely populated urban areas. The paper also examines the implications for urban planning and design, emphasizing the importance of incorporating water-based cooling methods into LCZ composition to improve urban resilience to heat stress.