Applying geospatial technology in assessing the coastal vulnerability of zaranik protectorate to sea-level rise

Abstract

Considering Egypt’s plan to develop eco-tourism within the Zaranik protectorate, ensuring the balance between the protectorate’s environmental protection and economic development has become an urgent need to maintain the protectorate’s sustainability. However, the protectorate lacks monitoring studies as well as assessing its vulnerability to sea-level rise (SLR) due to shoreline erosion. Accordingly, this study aimed at monitoring the shoreline dynamics of the protectorate over a period of 32 years (1987-2019) using geospatial technology as well as assessing its vulnerability to SLR due to shoreline erosion. The study divided the protectorate’s shoreline (32 km) into three zones (eastern, middle, and western). Digital Shoreline Analysis System (DSAS) tool was integrated into ArcGIS software to facilitate analyzing the historical shoreline dynamics for both long-(1987–2019) and short-term time intervals (1987–1998, 1998–2001, 2001– 2014, 2014–2015, 2015–2016, 2016–2017, 2017–2018, and 2018–2019) from six Landsat and three Sentinel images. Six coastal parameters were used in estimating the coastal vulnerability index (CVI). Moreover, a coastal vulnerability map was generated to identify and highlight areas most susceptible to inundation by seawater along the protectorate. Results of shoreline analysis revealed that, during 1987–2019, the protectorate’s shoreline exhibited high erosion with an average rate of-1.03 ± 3.9 m/yr. Moreover, the tidal action, the prevailing wave directions, the oblique orientation of the shoreline, and the azimuth angle of the sandbar have all contributed in the eventual closure of Boughaz El-Zaranik since 2017. CVI results revealed that the entire coast is under the impact of very high vulnerability to SLR due to shoreline erosion. The vulnerability maps generated in the current study can be used to help in formulating the strategies required in SLR adaptation and mitigation along Zaranik protectorate’s coast.