Vertical displacement assessment in temporal analysis of the transboundary islands of Tiran and Sanafir, Egypt-Saudi Arabia

Tiran and Sanafir are coastal ecosystem islands located in the fragile environment of the Red Sea. The importance of the islands has always been bordering security for Egypt and Saudi Arabia. In the last decade, an economic value has been added to the border islands and has grown a significant importance to be the focal point between the two countries’ trade lines. The study is aiming at the temporal analysis of the SAR data phase estimation to map the island’s vertical displacement for the last 5 years. Temporal datasets of SAR images were collected from the European Space Agency, and dataset collection started from November 2016 until May 2020 to comprehend the objectives of the research study. The SAR interferometry techniques were implemented to estimate the phase displacement for 15 SAR data sets of the border islands. Consequently, the temporal analysis demonstrated the trend of the phase displacement during the study timeframe. Results indicated that the maximum island subsidence (−0.417 m) was estimated from the scene acquired on 21 Feb 2018, while the maximum uplift (0.708 m) value was conducted from the scene acquired on 17 Nov 2017. Moreover, the trend analysis showed an instability behavior among the successive SAR datasets. The current study’s findings are crucial to the decision-makers from Egypt and Saudi Arabia in realizing the predictability of the island’s displacement mitigations to ensure the sustainability of the incoming socioeconomic activities.