Coastal dynamics and risk assessment in the Gambia

Álvaro Enríquez-de-Salamanca; Álvaro Enríquez-de-Salamanca

doi:10.3934/geosci.2025034

AIMS Geosciences

2025, Volume 11, Issue 4: 806-827. doi: 10.3934/geosci.2025034

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Research article

Coastal dynamics and risk assessment in the Gambia

Álvaro Enríquez-de-Salamanca ^{1,2
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1.
Department of Biodiversity, Ecology and Evolution, Faculty of Biological Sciences, Complutense University of Madrid, Madrid, 28240, Spain
2.
Draba Ingeniería y Consultoría Medioambiental, San Lorenzo de El Escorial, 28200, Spain

Received: 07 July 2025 Revised: 25 August 2025 Accepted: 17 September 2025 Published: 09 October 2025

West African coasts are experiencing a significant retreat on average, albeit highly variable according to sections. Shoreline changes were analyzed in ten sections along the Gambian coast between 2011 and 2023. The results indicated a predominant retreat, ranging from 1.27 to 4.51 m per year, with the most severe retreat occurring in the northern part of the country. However, localized accretion zones were also detected, where the coastline has expanded by 0.54 m per year. Coastal vulnerability is linked not only to the intensity of erosive processes but also to the degree of urbanization. In areas with severe retreat but limited construction, sea advance forms new beaches inland, but in developed areas, it leads to the destruction of infrastructure and buildings, causing major social impacts. Coastal planning must be adjusted to accommodate the future evolution of the shoreline, enabling beaches to shift inland. While this may result in land loss, it will enable the preservation of beaches, a vital tourism resource for Gambia's economy.
- climate change,
- coastal retreat,
- coastal erosion,
- coastal hazard,
- coastal vulnerability
Citation: Álvaro Enríquez-de-Salamanca. Coastal dynamics and risk assessment in the Gambia[J]. AIMS Geosciences, 2025, 11(4): 806-827. doi: 10.3934/geosci.2025034

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Abstract

West African coasts are experiencing a significant retreat on average, albeit highly variable according to sections. Shoreline changes were analyzed in ten sections along the Gambian coast between 2011 and 2023. The results indicated a predominant retreat, ranging from 1.27 to 4.51 m per year, with the most severe retreat occurring in the northern part of the country. However, localized accretion zones were also detected, where the coastline has expanded by 0.54 m per year. Coastal vulnerability is linked not only to the intensity of erosive processes but also to the degree of urbanization. In areas with severe retreat but limited construction, sea advance forms new beaches inland, but in developed areas, it leads to the destruction of infrastructure and buildings, causing major social impacts. Coastal planning must be adjusted to accommodate the future evolution of the shoreline, enabling beaches to shift inland. While this may result in land loss, it will enable the preservation of beaches, a vital tourism resource for Gambia's economy.

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