Study on the long-term shoreline extraction and analysis method on the east coast of Korea using Python toolkit

  In recent years, with the development of computer vision analysis and the free release of satellite images, it has become possible to observe and evaluate coastal and shoreline changes through satellite images. However, the shorelines obtained by satellite detection are instantaneous at the time of satellite capture, and some correction processes are required to validate them with actual monitoring data and ensure their reliability.

  In this study, Landsat and Sentinel-2 satellite images, along with a Python toolkit, were used to analyze shoreline data over a 40-year period on the east coast of Korea. Validation was performed using national research monitoring data collected bi-quarterly over approximately 10 years for 9 sites. Data containing changes greater than the standard deviation and errors in the data itself were removed from the shoreline results. The accuracy of the shoreline data was corrected by comparing it with monitoring data and reflecting the conditions of offshore external forces.

  All of the shoreline changes over the past 40 years have shown a relatively stable change of less than 3m per year. However, there has been rapid continuous change over the past 10 years. This is likely due to recent coastal development, including direct and indirect impacts from artificial structures, nourishment effects, and natural erosion.

  Continuous collection and analysis of shoreline change data are necessary to ensure the stability and management of coastal buffer zones, including coastal hinterlands and sandy beaches, long-term equilibrium, and continuous shoreline changes caused by extreme typhoons, human impacts, and changes in artificial structures. Ensuring coastal resilience and stability through satellite data and analysis methods is crucial. We plan to detect continuous shoreline changes on both the east and west coasts of Korea. Furthermore, research will be needed on digital twin-based data display to ensure convenience for stakeholders and respond effectively to coastal erosion.