River Mouth Morphology Changes at the Nanakita River Mouth After The Great East Japan Tsunami

This study investigates the river mouth morphology changes at the Nanakita River mouth. The river mouth was greatly changed due to The Great East Japan Tsunami in 2011. The gradual process of river mouth changes was investigated using water level measurement data in the river and the sea. The correlation coefficient and the linear gradient between the two data sets were analyzed. Both of the parameter show that the river mouth morphology changes will have significant effects to the tide intrusion, hence their value will correspond to the river mouth condition. River mouth closure, as well as river mouth opening has been successfully detected. The proposed method in this study will provide an efficient way for analyzing and evaluating river mouth morphology changes.