Urban Heat Island Analysis: Green Roof Identification for Bengaluru’s Hotspots

Urban Heat Island (UHI) is a pressing environmental challenge in rapidly urbanizing cities like Bengaluru, where dense built-up areas experience elevated surface temperatures, adversely impacting urban living conditions and public health. The widespread increase in hard surfaces, coupled with the reduction of green spaces, intensifies the Urban Heat Island (UHI) effect by elevating surface temperatures, degrading air quality, and increasing energy demands for cooling. Green roofs, which leverage vegetation to reduce rooftop temperatures and promote urban cooling, offer a sustainable solution to mitigate these effects. This study aims to identify UHI hotspots in Bengaluru and evaluate rooftops suitable for green roof implementation. The methodology employs remote sensing, utilizing Land Surface Temperature (LST) derived from Landsat 8 thermal satellite imagery to pinpoint high-temperature zones. Building footprint data from sources like OpenStreetMap and Google Open Buildings are integrated with thermal data using Geographic Information System (GIS) tools to assess rooftop suitability. Key criteria include roof size (minimum 50 m²), mean temperature, and urban density, ensuring optimal site selection. The analysis identifies 179,587 suitable rooftops spanning 27.25 km², primarily in low- to medium-density areas. These findings provide actionable insights for urban planners and policymakers to strategically deploy green roofs, fostering urban cooling, enhancing air quality, and improving public health. By promoting sustainable urban design, this approach strengthens Bengaluru’s resilience to climate change and supports the creation of liveable, eco-friendly urban landscapes, aligning with global trends toward green infrastructure.