Wave storm impacts on shoreline evolution: A case study of iztuzu beach

Abstract

This study investigates the evolution of the Iztuzu beach shoreline and its response to wave storm characteristics and frequencies. Firstly, using the Digital Shoreline Analysis System (DSAS) tool, high spatial resolution satellite imagery, coastal changes were assessed over various time scales covering the decade of 2013-2022. Secondly, considering the same timeframes, wave storm characteristics occurrence and characteristics of Iztuzu beach were assessed. Lastly, the coastal evolution and wave storm assessment results are linked based on correlation analysis to define the relation between the observed coastal changes and the wave storm frequency and characteristics changes. Thus, the present study's main advance lies in considering the impact of some key characteristics of wave storms, such as storm duration, direction and total energy, on shoreline evolution. The correlation analysis of shoreline changes and storm characteristics revealed the influence of wave storms on coastal dynamics. The study results highlight the significant sensitivity of certain beach zones to storm characteristics and point out the possibility of predicting future shoreline changes using projected wave storm patterns. Throughout the study period, Zones II, III, and IV experienced consistent erosion, likely attributable to the interaction between the southwest-oriented shoreline and the prevailing storm wave direction from the South. This alignment generates strong drift currents, contributing to the observed shoreline retreat. For instance, the correlation exceeded 0.8 at Zones III, IV, and V for wave storm duration, SPI and TSWE against the EPR, and 0.7 at the same zones for the same characteristics against the LRR. As a result, coastal erosions at Iztuzu Beach are more linked to the intensity and duration of southern wave storms. Thus, this study emphasizes the importance of combining wave storm data and shoreline analysis to develop effective coastal management and mitigation strategies.