Shoreline change assessment for various types of coasts using multi-temporal Landsat imagery of the east coast of South Korea

ABSTRACT Shoreline change assessment is an important task for protecting coastal properties and preserving coastal environments. This research aimed to assess the shoreline changes using the multi-temporal Landsat imagery, acquired from the east coast of South Korea during 1994 and 2014. The procedure for the shoreline change assessment consists of the following steps: (i) generating the normalized difference water index (NDWI) map from each Landsat image; (ii) extracting the shorelines from each NDWI map through the thresholding method; and (iii) assessing the shoreline changes in the various types of coasts such as the sandy, rocky and harbour coasts using the checkpoints with 1 km intervals. The statistical results showed that 94% of the shorelines in the sandy coasts and 96% of the shorelines in the rocky coasts moved landward between 1994 and 2014 due to coastal erosions, while 91% of the shorelines in the harbour coasts moved seaward during the same period due to the land reclamation works. This research contributed to the assessment of the shoreline changes and the calculation of the erosion rates in the various coasts of the study area between 1994 and 2014.