Urban Heat Island Effect: Unplanned Urbanization and the Challenge of Nocturnal Cooling

The study identifies 'urban morphology'—the layout and configuration of city buildings—as a primary driver. Narrow 'street canyons' trap long-wave radiation, preventing heat from escaping into the atmosphere. Furthermore, the lack of blue-green infrastructure (water bodies and parks) exacerbates the problem. To mitigate these risks, the research advocates for the adoption of 'cool roofs'—surfaces designed to reflect more sunlight and absorb less heat—and a massive expansion of urban forestry. For policymakers, this necessitates integrating climate resilience into urban planning frameworks. Current Heat Action Plans (HAPs) in India often focus on daytime peaks; however, this study suggests that addressing night-time heat through building bye-laws and sustainable materials is equally critical for public health and energy efficiency. UPSC Relevance: This topic is highly relevant for GS Paper I (Urbanization and its remedies) and GS Paper III (Environment and Disaster Management). Aspirants can use the UHI effect as a case study for the 'unintended consequences of unplanned development' and link it to the National Mission on Sustainable Habitat and the need for climate-resilient infrastructure in Geography Optional papers.