Kupfer, SSantamaria-Aguilar, SVan Niekerk, LaraLück-Vogel, MelanieVafeidis, AT2021-03-102021-03-102020-10Kupfer, S., Santamaria-Aguilar, S., Van Niekerk, L., Lück-Vogel, M. & Vafeidis, A. 2020. Modelling compound flooding at the Breede Estuary, South Africa. http://hdl.handle.net/10204/11884 .http://hdl.handle.net/10204/11884Extreme coastal flooding along the South African coast can be caused by the co-occurrence of waves, storm surges and tides. Importantly, in low-lying areas such as estuaries, the additional influence of river discharge can further exacerbate flooding intensity. The CASISAC* project aims to assess these compound flood impacts on a local scale by modelling flood extents with input parameters generated from ocean and atmospheric models. In this study we model the flood extent and flood depth of compound flooding events, induced by high river discharge, large waves, storm surge and tides at the Breede Estuary, South Africa. We simulate compound flooding using the open source hydrodynamic model Delft3D by coupling the two modules FLOW and SWAN. The model input parameters are river discharge time series, observed tides, and modelled extreme water levels and waves. We use a high-resolution elevation model in combination with freely available global elevation data (MERIT) and bathymetry created by combining the freely available GEBCO dataset with nearshore bathymetric contour lines. We further analyse the influence of the individual flood drivers, i.e. coastal and river flooding, on flood extent and depth. Preliminary results show non-linear increases in flood characteristics when accounting for all flood drivers. We also observe that the combination of moderate intensity individual events can lead to extreme flooding. These results highlight that not accounting for compound flooding in coastal impact assessments may lead to the underestimation of flood impacts.FulltextenCompound floodingEstuariesBreede RiverCoastal floodingClimate changeCoastal systemsMarine systemsEcosystems processesConference PresentationKupfer, S., Santamaria-Aguilar, S., Van Niekerk, L., Lück-Vogel, M., & Vafeidis, A. (2020). Modelling compound flooding at the Breede Estuary, South Africa. http://hdl.handle.net/10204/11884Kupfer, S, S Santamaria-Aguilar, Lara Van Niekerk, Melanie Lück-Vogel, and AT Vafeidis. "Modelling compound flooding at the Breede Estuary, South Africa." <i>Coastal Hazards in Africa Conference, (virtual conference) Durban, South Africa, 27-29 Oct 2020</i> (2020): http://hdl.handle.net/10204/11884Kupfer S, Santamaria-Aguilar S, Van Niekerk L, Lück-Vogel M, Vafeidis A, Modelling compound flooding at the Breede Estuary, South Africa; 2020. http://hdl.handle.net/10204/11884 .TY - Conference Presentation AU - Kupfer, S AU - Santamaria-Aguilar, S AU - Van Niekerk, Lara AU - Lück-Vogel, Melanie AU - Vafeidis, AT AB - Extreme coastal flooding along the South African coast can be caused by the co-occurrence of waves, storm surges and tides. Importantly, in low-lying areas such as estuaries, the additional influence of river discharge can further exacerbate flooding intensity. The CASISAC* project aims to assess these compound flood impacts on a local scale by modelling flood extents with input parameters generated from ocean and atmospheric models. In this study we model the flood extent and flood depth of compound flooding events, induced by high river discharge, large waves, storm surge and tides at the Breede Estuary, South Africa. We simulate compound flooding using the open source hydrodynamic model Delft3D by coupling the two modules FLOW and SWAN. The model input parameters are river discharge time series, observed tides, and modelled extreme water levels and waves. We use a high-resolution elevation model in combination with freely available global elevation data (MERIT) and bathymetry created by combining the freely available GEBCO dataset with nearshore bathymetric contour lines. We further analyse the influence of the individual flood drivers, i.e. coastal and river flooding, on flood extent and depth. Preliminary results show non-linear increases in flood characteristics when accounting for all flood drivers. We also observe that the combination of moderate intensity individual events can lead to extreme flooding. These results highlight that not accounting for compound flooding in coastal impact assessments may lead to the underestimation of flood impacts. DA - 2020-10 DB - ResearchSpace DP - CSIR J1 - Coastal Hazards in Africa Conference, (virtual conference) Durban, South Africa, 27-29 Oct 2020 KW - Compound flooding KW - Estuaries KW - Breede River KW - Coastal flooding KW - Climate change KW - Coastal systems KW - Marine systems KW - Ecosystems processes LK - https://researchspace.csir.co.za PY - 2020 T1 - Modelling compound flooding at the Breede Estuary, South Africa TI - Modelling compound flooding at the Breede Estuary, South Africa UR - http://hdl.handle.net/10204/11884 ER -24354