Evolutionary trends of the Niger Delta shoreline during the last 100years: Responses to rainfall and river discharge

Abstract

article There is growing evidence that the world river deltas are influenced by climate change and anthropogenic activ- ities.In this study,shoreline changesalong the Niger Delta coastoftheGulf ofGuinea,NorthAtlanticOceaninthe last ten decades were investigated. The relationships between these changesand hydrometeorologic variables of rainfall and river discharge were considered. Topographic maps and satellite imagery, in addition to rainfall and hydrological data from the lower Niger River basin, were used for the study. The results show two distinct shoreline dynamics patterns/phases: first, mobility with high net retreat between 1923 and 1987 interval and; second, mobility with low net progradation from 1987 to 2013. During the first phase, shoreline retreat is mainly concentrated on the western and arcuate sections of the delta. In the second phase, all sections of the Niger Delta coast prograded seaward. Strong correlations between: shoreline change and the river discharge (R 2 = 0.95), shoreline change and rainfall variability (R 2