Analysis of urban heat island using remote sensing products: A case study of the city of Banja Luka

Abstract

The thermal characteristics of urban areas differ from the thermal characteristics of the surroundings. The phenomenon of urban heat islands exists both in large urban areas and in smaller medium-sized areas. In the research of urban heat islands, there are two main approaches - direct measurements of air temperature in the field and reading temperatures from remote sensing products. In this study, remote sensing products from Landsat 8 and Landsat 9 missions were analyzed to determine differences in thermal characteristics of specific land use types within the territory of the city of Banja Luka. A total of 23 satellite images from various months of 2023 were collected, and the thermal characteristics were analyzed using an image from July. Considering the terrain's relief complexity in the observed area, the analysis also included the aspect of elevation levels. The research results indicate that built-up areas generally have higher temperatures compared to other land use classes by at least 2°C. The lowest average temperatures were observed in forest and water surface classes. Looking at elevation zones, the highest average temperatures were recorded in the first elevation zone up to 200 meters above sea level, reaching 30.4°C. All analyses were conducted using open-source software packages. The findings of this research can be beneficial for various sectors such as spatial/urban planning, health, energy, water management, forestry, and similar fields. Additionally, the research results can contribute to future detailed studies focusing on defining local climate zones and thermal variations within them.