Mapping the Vulnerabilities of Coastline Cities and Communities in Africa to Adapt to Climate Change: A Study of Lagos-Nigeria

IBEABUCHI Uwadiegwu; Nwilo Peter Chigozie

Abstract

The Lagos coastline is active in nature and is located about less than six feet above sea level and houses about half of 15 million people in Lagos state, and is vulnerable to changes in coastline due to flooding and erosion. Climate change has aggravated this; sea-level rise will increase the risk of storm surge flooding, and coastal erosion threatening coastal cities. The annual rainfall along the coastline of Lagos was modeled and then estimated between 1975 and 2015 with a mean value of 9.34 mm/day, 8.99 mm/day in 1975, 9.27 mm/day in 1984, 9.78 mm/day in 2000, 8.87 mm/day in 2011 and 9.24 mm/day in 2015. Shoreline change analysis along the coastline of Lagos was conducted using historical shoreline positions spanning 40 years from 1975 to 2015. The rates of shoreline change were calculated for a total of 734 transects covering 31.782km (19.748 miles) of shoreline. The Net shoreline movement between 1975 and 2015 was estimated to have a minimum value of 0.009m and a maximum value of 162.26m, and a mean value of 39.13m. Coastal erosion along shoreline was estimated to be 0.0002 m/year minimum and a maximum of 4.05m/year, and a mean of 0.97m/year with a standard deviation of 0.86 m/year between 1975 and 2015. Further analysis reveals thatrainfall induced by climate change was found to have a strong relationship with changes in shoreline along the coastline of Lagos over years. The major highways and properties in the areas have been virtually destroyed in many portions, as case of Goshen estate in Lekki, Ahmadu Bello way in Victoria Island and Lagos Eko Atlantic city project by increased rainfall,flooding and coastal erosion. This region had undergone severe geomorphologic changes due to natural as well as human interventions and this posesa threat. This study concludes that the shoreline of Lagos coast is under heavy erosion and needs scientific and management attention.Keywords:Climate change, coastal erosion, coastline/shoreline, Lagos,net shoreline movement, rainfallCite this ArticleNwilo Peter Chigozie, Ibeabuchi Uwadiegwu.Mapping the Vulnerabilities of Coastline Cities and Communities in Africa to Adapt to Climate Change: A Study of Lagos-Nigeria.Journal of Alternate Energy Sources & Technologies. 2020; 11(1): 1–14p.