LST-based threshold method for detecting UHI in a complex urban landscape

Abstract

Urban Heat Island (UHI) explains the occurrence of excessive heat that spread unevenly in urban areas. Intense and complex human activities in urban areas are mainly causing the formation of UHI. This study aims to identify the spatial characteristics of UHI in a complex urban feature, like the Universitas Indonesia campus area and its surroundings in Depok City. The campus and its surroundings might represent a complex urban area and can be used as a reference to understand the widespread impact of UHI. UHI was determined based on the threshold value, calculated from the average and standard deviation of the surface temperature. This study utilized Landsat 8 OLI-TIRS imagery to extract Land Surface Temperature (LST) value. The LST observations were collected for three different periods, including 2013, 2017, and 2021. The LST value tends to be increased during these times, with the LSTmax recorded at 34.68 oC, 35.47 oC, and 36.4 oC for 2013, 2017, and 2021, respectively. Based on the number of the accommodated grid, the UHI was getting larger every year. Started from 313 grids in 2013, the UHI has been expanded to more than 550 grids in 2021.