Climate change and coastal erosion hotspots in West Africa: The case of Togo

Global warming is a worldwide phenomenon with disastrous implications ranging from ocean warming and glacier melting to sea level rise and coastal damage. This research assesses climate change trends, investigates coastal erosion hotspots and forecasts shoreline dynamics in West Africa. It also includes information on coastal erosion impacts and current coastal defence measures. The data set includes annual mean sea level anomaly, eddy kinetic energy, wave energy data and monthly climate data, such as precipitation, temperature, wind speed, and sunshine, from 1988 to 2023. Additionally, field survey data and Sentinel-2 satellite images were employed from 2015 to 2023 for coastal erosion monitoring. The Mann-Kendall test and Sen's slope test have been employed for climate trend analysis, while the DSAS tools have been used to identify coastal erosion hotspots and forecast future trends. The results revealed a significant increasing trend in annual sea level rise anomaly, annual wave energy, annual eddy kinetic energy, monthly temperature, and monthly sunshine. According to the shoreline dynamics investigation on Togolese coastal area, the Aflao-Port transect had significant accretion rates (up to 15 m/years), whereas the Port-Aneho transect experienced coastal erosion (up to -12 m/years). Climate change may increase wave energy intensity in certain regions, while coastal development can alter littoral transport and shoreline changes. Although there are soft and hard stabilisation solutions to counteract coastal erosion, such as groynes, sandbags, reforestation, and a series of nozzles in Togolese coast, the phenomenon of coastal erosion has evolved in recent years. Future projections in 2033 show that coastal erosion could move from 50 to 250 m inland. It is recommended that climate trend indicators, shoreline dynamics, and coastal stabilisation solutions be incorporated into all coastal and marine policies for sustainable management, with a view to ensuring minimal disruption to the ecosystem services provided by the sea and coast to people.