Spatial and Temporal Analysis of Beach Elevations for Monitoring Coastal Erosion for Sustainable Development: A Case Study of Ola Beach in Cape Coast, Ghana.
Beach profiles are important tools for understanding long-term trends of erosion, accretion and predicting the future evolution of coastal landforms. Beaches are required to be monitored for their sustainable development given their ecological and economic roles in coastal economies. In developing countries, this is particularly important in the context of sea level rise resulting from climate change and poor land use in coastal areas. This paper presents a simple and cost-effective educational tool for coastal erosion monitoring. Employing the Emery technique as the assessment tool, data was collected on a fortnight basis from January- March, 2012 at low tides at the Ola Beach in Cape Coast, Ghana. Mean elevations of the beaches relative to the shoreline were determined as the primary mode of analysis based on four 100 m transects of 20 m intervals laid perpendicular to the shoreline. One way Analysis of Variance (ANOVA) test was used to assess variations in mean beach elevations. The results of a one way ANOVA (p-values of 0.257 and 0.112 for spatial and temporal profiles respectively) suggest that each of the four profiles did not experience any significant changes in elevation over the six survey period. Even though there were no significant differences (p˃0.05) in mean elevation for both spatial and temporal profiles during the survey period, the data generally suggests that the active shoreface was prone to erosion. It is therefore recommended that for this particular beach, protection measures have to be considered for the adjoining dunes in order to avert possible future catastrophic impacts of coastal erosion. On the basis of the findings, it is possible that beach profiles provide important shoreline position data for geometric evaluation of beaches over time.