Analysis of urban heat islands combining Sentinel 2 and Landsat 8 satellite images in Hochiminh city

Abstract

Abstract Urbanization in big cities has led to many impacts, the most obvious of which is the increasing of impervious surfaces from urban areas, socio-economic construction, concrete roads and the reduction of green space (vegetation, water surface). The changes land use land cover (LULC) led to the changes in the land surface temperature (LST), the formation of urban temperature islands (UHI), which have changed the local climate. This study combined Landsat 8 and Sentinel 2 images to enhance the process and calculation of LST value, spatial resolution was improved to 10m compared to 30m when calculated by Landsat 8 image. In which, the study also used ArcGIS software to classify 4 land surface covers, namely built-up land, vegetation land, water surface and the other land in order to monitor the urbanization process (with kappa coefficients all over 0.8) and assess the trend of changing LST on each LULC in the period 2015 - 2022. The results showed that when combined with Sentinel 2 images, LULC such as built-up land, roads and vegetation cover were more prominent, helping to improve more accurate results when calculating LST. Besides the trend of urbanization development in Ho Chi Minh city, it also leads to changes in the distribution of UHI over time.