Seasonal Analysis of Land Surface Temperature and Urban Heat Island Dynamics: A Comparative Study of Kochi and Fairbanks

Abstract

This study investigates the seasonal and decadal dynamics of Urban Heat Island (UHI) effects and Land Surface Temperature (LST) trends in two climatically distinct cities—Kochi, India, and Fairbanks, Alaska—from 2000 to 2023. Using MODIS and Landsat 8 datasets analyzed using Google Earth Engine, we examine variations in LST and UHI intensity during summer and winter. Kochi, a tropical city, exhibits a pronounced increase in LST, with a decadal warming trend of 0.07°C per year in summer and 0.08°C per year in winter. Conversely, Fairbanks, a subarctic city, shows a modest summer LST rise of 0.04°C per year and a slight winter cooling trend (-0.003°C per year), influenced by increased snowfall and albedo effects. UHI intensity in Kochi reveals an amplified winter effect, with a spatial expansion of high-UHI zones from 2014 to 2023, reflecting urbanization and reduced vegetation cover. In contrast, Fairbanks demonstrates a slight summer UHI intensification but reduced winter UHI extent, aligning with its cooling trend. Comparative analysis highlights the contrasting impacts of urbanization and climatic conditions on UHI formation and evolution across the two cities. This study underscores the necessity for tailored mitigation strategies, emphasizing green infrastructure in tropical cities and adaptive urban planning in subarctic regions, to address region-specific thermal stress and enhance urban climate resilience.