Decoding Urban Heat: A Decadal Analysis (1991-2021) of Land Surface Temperature and Thermal Comfort Dynamics in Coastal Taluka of Bardez, Goa, India

The urban heat island phenomenon refers to the alteration of the climate in urban areas resulting from the disruptions caused by urban development. This issue is of immense concern for the vast number of individuals living in cities. The rural regions across the world are diminishing at a rapid rate, leading to significant transformations in land use and land cover. The dynamics of urban thermal comfort is closely linked to these changes. The assessment of urban thermal comfort levels can be accomplished through the utilization of the urban thermal field variance index (UTFVI) which is derived from LST data. The study reveals that Bardez taluka, located in Goa, India, has witnessed substantial alterations in land use and land cover over the past three decades, primarily due to economic advancement and population growth. From 1991 to 2021, the Urban thermal field variance index (UTFVI) in the Bardez taluka has shown a clear upward trend, indicating increased temperature fluctuations in urban areas. This rise has negative effects on residents' comfort, as the size of land offering "excellent" comfort has decreased from 37.30 sq. km (14.76%) in 1991 to 27.05 sq. km (10.71%) in 2021 showing a decrease of 4.05 %. Conversely, areas with the "worst" comfort level have increased from 13.98 sq. km (5.54%) to 38.17 sq. km (15.11%) showing a 9.57% increase during the same period. These changes are influenced by factors like urbanization, impenetrable surfaces like asphalt and concrete, towering structures and crowded infrastructure, minimal green areas, altered microclimate, human actions such as industrial processes, transportation and energy consumption, which can create urban heat islands and raise overall temperatures in cities. These findings carry significant implications for urban planning, policy-making and sustainable development. In addition, the study provides important insights into the consequences of anthropogenic actions and alterations in land use on urban heat and thermal comfort.