MONITORING LAND SUBSIDENCE IN EGYPT’S NORTHERN WEST COAST USING INTERFEROMETRIC SYNTHETIC APERTURE RADAR

Abstract. The northern west coast of Egypt has experienced significant development and urbanization in response to its growing population. This has resulted in the construction of many new cities along the Mediterranean Sea shore, making the region a major attraction for both economic and recreational purposes. However, this rapid growth has also created a need for continuous monitoring to ensure environmental and economic sustainability and to identify potential hazards. Remote sensing techniques, such as satellite imagery and interferometric synthetic aperture radar (InSAR), have proven to be effective tools for monitoring remote regions. However, InSAR has some limitations, such as susceptibility to tropospheric and ionospheric delays as well as baseline errors. To address these limitations, this study utilized a differential technique that uses the phase difference between two nearby pixels to reduce the spatially correlated atmospheric and baseline errors. In this study, Sentinel-1 SAR images were used to create a single master InSAR stack covering the study region from 2018 to 2023. The estimated land surface velocities showed a subsidence motion of 10 to 15 mm/year in the region of Marsa Matruh city, which is consistent with existing urbanization and agricultural activities. The findings of this study highlight the importance of continuous monitoring and the potential of remote sensing techniques for identifying potential hazards and ensuring sustainable development.