Developing a flood hazard analysis framework in the Cuvelai Basin, Namibia, using a flood model, remote sensing, and GIS [article]

Frans C. Persendt, University Of Canterbury
Worldwide, more than 40% of all natural hazards, and about half of all deaths, are the result of flood disasters. In the Cuvelai River Basin (CRB), northern Namibia, flood disasters have increased dramatically over the past half-century, along with associated economic losses and fatalities. The increase in hydro-meteorological hazards such as floods are mainly attributed to intense urbanisation, changing land-use patterns and a changing climate. These hazards are exacerbated in semi-arid and
more » ... a-sparse (SADS) regions such as the CBR, because of declining and/or non-existent hydro-meteorological infrastructure. In addition there is a lack of long-term continuous records that is needed to enhance the implementation of traditional flood risk management strategies, whether structural or non-structural, to mitigate hydro- meteorological hazards. This thesis developed a systematic framework that has quantified the uncertainties associated with the hydrological cycle that preclude the development of flood risk management strategies. The framework is based on free-data and open-data and software that is available online. It used remotely sensed data validated against ground-based observational data, where available. The particular components of the hydrological cycle that are assessed are: precipitation, surface runoff (discharge), surface water extent and surface water movement pathways (drainage networks). Hydrologic modelling was used to model the water fluxes in order to derive basin as well as flood characteristics of the study area. The framework can be used as a benchmark for the development of flood risk management policies that will enable SADS regions to mitigate the severe effect hydro-meteorological disasters in the Anthropocene. The flood hazard analysis framework (FHAF) developed for this study consists of two steps: (a) preliminary analysis and (b) hazard estimation. The preliminary analysis enable the development of a hydro-meteorological (floods and droughts) archive using different data sources as well [...]
doi:10.26021/6617 fatcat:rbf3m4oqnneb5geghhduoce3mi