Remote sensing application in monitoring change of river and coastlines of Morong, Bataan, Philippines

Abstract

Remote sensing offers fast, cheap and reliable method in detecting river and coastal changes. In this study, satellite imageries of Morong river and coastlines from 2006 to 2016 were collected and analyzed to monitor changes. Field measurements were also done using South Total Station (NTS-362R6L) in 2016 for comparison and validation of data. Results showed that the river outlet and the riverbank increased in width size due to erosion brought about by torrential rains and urban run-offs. Coastlines near the river narrowed in size or shifted landward due to coastal erosion and sea level rise. An interview was conducted to locals residing nearby the river and coast where strong typhoons were reported which cause geophysical changes in the area. The residents also observed sea level rise, coastal and river erosion which caused narrowing of the coastlines and widening of the river, respectively. Records of high tides and low tides collected were projected in annual average levels per month. The average level of low tides increased per year which can be a result of sea level rise. The computed RMSE between field and remote sensing measurements ranged from 0.1m to 0.67m which indicated positional accuracy of Google Earth in the area.