Determination and Mitigation of Urban Heat Island (UHI) In Lahore (A comparative Study of Landsat 8&9)

Abstract

The term "Urban Heat Island" (UHI) refers to a city or metropolitan area that is significantly warmer than its surroundings. Heatwaves are one of the most visible hazards associated with UHI, that intensified exponentially over the last two decades. The overall approach of the study is initially based on a review of the literature and qualitative studies. The findings were applied to the case study to obtain empirical shreds of evidence. The study investigated the spatiotemporal urbanization trends and their impacts on UHI in Lahore, Pakistan, using multiple datasets. By identifying thermal drivers and simulating the spatial pattern, the direct relationship between development patterns and thermal properties can be visualized. To identify hot spots multi-temporal Landsat TM/OLI satellite images were processed using GIS and remote sensing techniques. It also investigates urban green spaces using spectral indices like the Normalized Difference Vegetation Index (NDVI). The findings indicate that Lahore's urbanization trend is intensifying in both existing and newly proposed zones which increases the pressure on land use planning. The negative correlation between Land Surface Temperature (LST) and NDVI confirms urban sprawl at the expense of green spaces, reshaping and aggregating the UHI profile of Lahore. These methodologies were combined to create UHI mitigation strategies that may aid communication among various stakeholders, including those in academia, development authorities, planners, and practitioners of the built environment. LST calculation by Landsat 9 proved efficient in comparison to Landsat 8 which may be due to improvement in spatial and spectral domain in architectural design Landsat series.