Thermal Mapping and Land Cover Correlation to Support Heat Island Mitigation in Jombang Regency Using Remote Sensing Data Tarisa Fadilah, Luisa Febrina Amalo, Novia Ramadhani
Center for Environmental Research, IPB University, Bogor, Indonesia
Conservation of Forest Resources and Ecotourism Study Program, Faculty of Forestry and Environment, IPB University, Bogor, Indonesia
Abstract
Land cover change in semi-urban areas can affect the increase of surface temperature, thus contributing to the formation of the urban heat island phenomenon. This study aims to analyse the spatial relationship between land surface temperature (LST), normalised difference vegetation index (NDVI), and normalised difference built-up index (NDBI) in Jombang Regency, East Java Province, Indonesia, during the dry season of 2024. Data were obtained from Landsat 8 and Sentinel-2 satellite images that had been filtered based on cloud cover levels of less than 20%. The researchers analyzed the data to calculate surface temperature values, vegetation density measurements, and built-up area intensity measurements. The results showed that the average surface temperature is 29.86 degrees Celsius with a minimum value of 15.02 degrees Celsius and a maximum of 44.68 degrees Celsius. The NDVI value of 0.35 indicated moderate vegetation control, but the NDBI value of -0.097 showed undeveloped land as the main land feature. The Pearson correlation analysis showed that vegetation index values had a small negative relationship with surface temperature readings (r = -0.20) and built-up index values had a small positive relationship with surface temperature readings (r = +0.25). A very strong negative correlation was found between vegetation index and built-up index (r = -0.85), indicating the conversion of vegetative land into built-up areas. These results suggest that although vegetation cover exists throughout Jombang District, the spatial arrangement of green infrastructure may not be suitable for reducing surface heat. The research shows that green open spaces require deliberate planning to achieve their full potential in reducing heat and enhancing climate resilience within urban development areas.
Keywords: built-up index, remote sensing, surface temperature, vegetation index
