Using the Normalized Difference Built-up Index (NDBI) to Monitor Urban Growth in Tajoura Municipality

Abstract

This study aims to monitor urban growth in the city of Tajoura between 2010 and 2025 in order to examine the magnitude and spatial direction of urban expansion using modern geospatial technologies, including Geographic Information Systems (GIS) and Remote Sensing (RS). The analysis was based on two satellite images acquired from Landsat 5 and Landsat 8, downloaded from the United States Geological Survey (USGS) database. Following the necessary preprocessing procedures and the extraction of the study area, the Normalized Difference Built-up Index (NDBI) was applied separately to each image due to differences in the spectral bands of the two satellite sensors. This approach enabled the differentiation between built-up areas and other land-cover categories, including vegetation cover and bare land. The study employed descriptive–analytical and historical approaches to investigate the patterns of urban development. The results indicate a significant and largely unplanned increase in urbanized areas during the study period. Built-up land expanded by approximately 15.7%, increasing from 89 km² in 2010 to 103 km² in 2025. In contrast, areas characterized by natural vegetation, cultivated land, or bare surfaces declined from 349 km² in 2010 to 335 km² in 2025. These findings highlight the ongoing urban expansion in Tajoura and its associated impacts on surrounding land-cover types.