Combating the heat island effect with drone-based thermal visualization

This article describes the methods, findings, and potential future applications of drone-based thermal visualization for mitigating urban heat islands. The heat island effect intensifies from human-made materials and infrastructure that absorb and retain solar radiation. Thermal sensors on satellites, with a resolution of 30 by 30 meters per pixel (baseball diamond-sized), are effective for broadscale regional and citywide heat assessment but cannot visualize the microscale local heat effects. To visualize the localized scale of heat, a novel process using unmanned aerial vehicles or drones was developed for this study that created thermal maps of a public streetscape targeted for revitalization in the greater Detroit metropolitan area of Ann Arbor, Michigan, including plans for new shade trees, green space, and hardscapes. Drones have the capacity to capture microscale thermal imaging at a resolution of less than 1.5 by 1.5 centimeters per pixel. This study aimed to understand the thermal behavior of common urban materials, quantify surface area by temperature at solar noon, and reveal the diurnal variation of the heat island effect. The method in this article was used to establish the preconstruction thermal data baseline and assess the effectiveness of the revitalized streetscape in reducing the heat island effect.