Certain communities along the coast of Ketu South Municipality in south-eastern Ghana, remain vulnerable to coastal flood events from storm surges, high tidal waves, lagoon overflow, and heavy rainfall. However, the local conditions that make these communities vulnerable are poorly understood and knowledge on which communities are most vulnerable is lacking. This study improves the conceptual understanding of different dimensions of vulnerability that exist across the communities and the various levels of vulnerability that each exposed community exhibits. The study surveyed 354 household heads from selected flood-prone communities including Blekusu, Agavedzi, Salakope, Amutsinu, and Adina. The survey collected data on demographic, social, economic, physical, exposure, and adaptive capacity to flood hazards. The data was then used to construct composite vulnerability indices at community levels. Results from the study demonstrate that the communities have different levels of vulnerability as a result of differences in their exposure, sensitivity, and adaptive capacity levels. The willingness to relocate as an adaptation strategy was determined by household flood duration, number of livelihoods, and sea defence preference. These results are relevant to flood disaster management programs and the adoption of effective adaptation measures that take into account local knowledge. The findings imply that interventions aimed at reducing vulnerability should take into account household characteristics, as well as flood exposure, and adaptive capacity factors.

Bathymetry is a critical input to storm surge models on coastlines fronted by lagoon systems, yet few studies explore how variations in bathymetry influence flood impacts, flooded extent, and exposed population across these globally widespread morphologies. Here, we investigate the influence of variations in bathymetry on storm inundation impact estimates across a continental shelf lagoon system. We explore how flooded extents and exposed population estimates from a 1% storm for Belize vary with estimated depths by comparing three existing bathymetries over a northern shallow, enclosed lagoon and a central deeper, open lagoon system with a newly developed bathymetry data set, Satellite‐Derived Bathymetry Enhanced Data set‐SDBED. We compare multiple bathymetric data sets to understand the influence on the flood uncertainties and the quantity of the impact of exposed population estimates. Our results show that greater estimated lagoon depths consistently result in lower predicted flood impacts for both lagoon systems in almost all cases. Unexpectedly, for one bathymetry with a median depth of 2 m in the northern lagoon, we find that a reduction in lagoon volume by 59% reduces total inundation volume by 45%. Our findings also show how vertical uncertainties in the SDBED bathymetry propagate through the model, resulting in variations of up to 12% in flood extents and up to 2% in exposed populations.