Application of remote sensing technique for shoreline change detection in Ninh Binh and Nam Dinh provinces (Vietnam) during the period 1988 to 2018 based on water indices

In the recent years, the Ninh Binh and Nam Dinh shoreline had a strong fluctuation due to the impact of natural conditions and economic activity of people. Therefore, the monitoring of shoreline changes is very important for coastal manage in the context of climate change today. In this study, a total of 5 scenes of Landsat 5 TM and 01 scene of Landsat 8 OLI/TIRS satellite images from 1988 to 2018 were used to extract shoreline based on water indices, such as Automated Extraction Water Index (AWEIsh, AWEInsh), Normalized Difference Water Index (NDWI) and Modified Normalized DifferenceWater Index (MNDWI). Assessing the accuracy of automatically extracted shorelines on Ninh Binh and Nam Dinh coastal from Landsat data show that, the accuracy of shoreline extraction using AWEIsh index is higher than using other water indices, which is reflected in the comparison of mean square error (MSE) and Kappa values. The results show that the coastline of Nam Dinh area tends to erode in the period 1988-2018, in which the most eroded length amounted to 987 m. Meanwhile, the coastal area of Ninh Binh province is strongly accreted, with the lengths of accretion amounted to several kilometers in period 1988-2018. The results obtained in the study provide timely informations to help managers on monitoring and protecting coastlines and coastal ecosystems. © 2020 Geophysical Center of the Russian Academy of Sciences. All rights reserved.