Authors: Praveen Kumar Yadav, Kundan Bhushan, Er. Manoj Kumar Yadav
Abstract: Rapid urbanization is a primary driver of local climate change, leading to the formation of the Surface Urban Heat Island (SUHI) effect, which poses significant environmental and public health challenges. This study presents a comprehensive spatiotemporal analysis of the SUHI phenomenon in Lucknow, India, over a decade (2014–2024) by leveraging the analytical power of the Google Earth Engine (GEE) platform and ArcGIS. Using annual mean Land Surface Temperature (LST) derived from Landsat 8 thermal imagery, we employed two distinct metrics to quantify the SUHI effect: statistical Urban Hot Spot (UHS) analysis and the Urban Thermal Field Variance Index (UTFVI). SUHI hotspots were identified as areas with LST exceeding two times standard deviations above the regional mean (LST > μ + 2σ), while the UTFVI was used to classify the urban environment into six levels of thermal comfort. The results reveal a significant intensification and spatial expansion of the SUHI effect over the study period. The total area identified as a Urban hotspot increased from 25 km² in 2014 to 26 km² in 2024, a growth of over 4%. Concurrently, the area experiencing the worst ecological conditions ("Worst" UTFVI zone) expanded from 1,038 km² to 1,050 km² a growth of 1.16% . These high-temperature zones are predominantly concentrated in the city's central commercial core and newly developed residential areas, correlating with the expansion of impervious surfaces. This research provides quantitative evidence of Lucknow's escalating thermal risk and underscores the utility of GEE and geospatial indices for monitoring urban environmental health. The findings offer critical insights for policymakers and urban planners to develop targeted heat mitigation strategies, such as the strategic implementation of green infrastructure.
