Rate of Sea Level Rise in Selected Coastal Community in the Niger Delta Region of Nigeria

Abstract

This study assessed the rate of shoreline change and sea level rise along the coast of the Opobo Kingdom in Nigeria's Niger Delta, one of the most vulnerable coastal regions in West Africa. Due to its low-lying terrain and vulnerability to tidal forces, the area was increasingly threatened by erosion and land loss brought on by climate change. The Digital Shoreline Analysis System (DSAS) was used in the study to measure shoreline dynamics using multi-temporal Landsat satellite imagery from 1984, 2000, 2012, and 2020. It evaluated both short- and long-term coastal changes by computing change statistics like End Point Rate (EPR) and Linear Regression Rate (LRR). For a more thorough spatial analysis, the study area was separated into three zones (A, B, and C). The findings demonstrated a dominant trend of erosion along the shore. At an average LRR of -5.89 ± 3.00 m/year, Zone B was found to be the most dynamic section, whereas Zone A displayed the lowest erosion at -2.23 ± 0.75 m/year. Over the course of the 36-year study period, the average LRR for the entire area was -3.94 ± 1.28 m/year, which suggests a steady rate of coastal retreat. These patterns were influenced by a number of factors, including underlying geology, tidal and wave energy, embankment conditions, and human activities like boat wave impacts and sand mining. Conversely, places with natural backstops and vegetation demonstrated greater resistance to shoreline retreat. The study emphasized the necessity of combining local knowledge with geospatial tools in adaptation planning and supplied crucial data for Niger Delta coastal zone management. Its results provided a transferable methodology for monitoring and mitigating shoreline change in other vulnerable deltaic environments around the world, and they also supported the design of site-specific interventions.