Remote Sensing-based Spatiotemporal Analysis of Near-Surface Temperatures for Cities Located in Different Climatic Zones

Urbanization has a major impact on the spatio-temporal variation of near-surface temperature for world cities. Recent studies indicate that the understanding of changes in temperature with urbanization has provided greater insights into the effects of Urban Heat Islands (UHI) on various issues such as excessive energy consumption, health hazard and climate change. In this study, spatio-temporal variations of near-surface temperature for India’s three major cities with different climatic conditions are evaluated. In addition, an attempt is made to establish a quantitative relation between land surface temperature (LST) and various geographical indices indicating vegetation cover (NDVI, Normalized Difference Vegetation Index), water surfaces (NDWI, Normalized Difference Water Index), and impervious land (NDBI, Normalized Difference Built-up Index). The dataset is selected for years 2014 to 2020 for three major cities: (i) Chennai (coastal); (ii) Hyderabad (inland); and (ii) Mumbai (coastal). The study uses Landsat – 8 OLI / TIRS images to derive land use/cover types, land surface temperature datasets, NDVI, NDBI, and NDWI. The preliminary evaluations indicate that the maximum contribution towards the UHI is impervious land, and the effect is more prominent in the areas of rapid urbanization. Urban areas relatively have a high temperature compared to the surrounding rural areas, and the effect is more prominent during night times. The analysis derived from the study will be useful for decision-makers or stakeholders to take necessary actions for reducing the effects of UHI and planning for urban sprawl.