Analysis of the impact of land cover on Surface Temperature Distribution: Urban heat island studies i}n Medan and Makassar

The increasing number of an urban population in Indonesia causing Urban Heat Island (UHI) phenomenon that has to be the concern for the local government. Urban Heat Island is a phenomenon of the surface and thermal air climate that is warmer than the surrounding non-urbanized areas due to population density. This phenomenon is identified by the growing number of impervious surface area that can store heat energy better than any other surface area. A ground-based temperature monitoring system can observe this symptom but on a smaller scale. If we want to monitor the UHI in a larger spatial scale, we need to set up a much more ground-based temperature monitoring system, and that would cost too much money. Satellite-derived Land Surface Temperature (LST) may be the solution to this problem. In this study, the UHI phenomenon was examined in two cities in Indonesia: Medan and Makassar using Landsat 8 OLI/TIRS imagery. The Single Channel Algorithm (SCA) was used to retrieved LST data. Spectral indices such as Normalized Difference Vegetation Index (NDVI), Modified Normalized Difference Water Index (MNDWI) and Visible Red-Near Infrared Build up Index (VrNIR-BI) were used. The mean LST in Medan and Makassar was 30.46°C and 30.76°C respectively. The study revealed that mean LST in the vegetation area was the coolest among the impervious and the mixing area. The Pearson Product Moment Correlation to analyze the relationship between land cover that is represented with NDVI values and LST in those study area shows that they have negative relationship. The correlation coefficient between NDVI values and LST in Medan and Makassar was-0.65; and-0.63. While the correlation coefficient between VrNIR-BI values and LST in Medan and Makassar was 0,65 and 0,63 respectively.