An Improved Method to Detect Shoreline Changes in Small-Scale Beaches Using Google Earth Pro
T.W.S. Warnasuriya, M.P. Kumara, Sudheera S. Gunasekara, Kuddithamby Gunaalan, R.M.R.M. Jayathilaka
Abstract
Shoreline change studies in small-scale beaches require high-resolution satellite images. In this regard, high-resolution satellite images from Google Earth (GE) would be an alternative source however novel studies are needed to verify the effectiveness and the efficiency of applying those images for shoreline change detection in small-scale beaches. Addressing this gap, the current study attempts to develop a new method. Accuracies of delineated shorelines under different scenarios were used to develop relationships with digitizing methods and used eye-altitude to estimate the most effective, efficient and productive method. This was done using Digital Shoreline Analysis System (DSAS) in ArcGIS software. It was found that the eye-altitude influences on digitizing accuracy and it could be improved when increasing the zoom level of the image which is under investigation. Maximum zoom level (50 m) used in this study showed the highest accuracy in shoreline digitizing while the most productive eye-altitude for shoreline delineation was found as 300 m. The current study identified that GE coupled with DSAS tool in ArcGIS software can be used as an effective and efficient method for small-scale shoreline change analysis and it is suggested that this methodology could be adopted for other similar studies.