Flooding in deltas and estuaries is driven by the interactions of oceanographic, hydrological, and meteorological phenomena such as extreme rainfall, river discharge, storm surge, and wave action. When these co-occur in space and time, they can exacerbate the flood extent, depth, and duration locally, resulting in a so-called compound flood event.
These events have the potential to cause large social and economic impacts and can directly or indirectly impact flood emergency response and infrastructure. This study shows the impact of these concurrent events on global flood risk and evaluates potential strategies for reducing this risk. Current global flood risk models assess either river or coastal flood risk, neglecting extreme compound river and coastal flood risk processes. This is problematic, as ignoring the temporal dependence between river and coastal floods could lead to underestimations of risk. To address these issues, the objectives of the proposed research are to:
- Develop the first globally applicable model for consistently assessing flood hazard at the river-coast interface.
- Improve our understanding of the influence of compound river and coastal flood events on flood risk.
- Develop a new integrated global flood risk assessment framework, tailored to highly populated regions at the river-coast interface.
This research is conducted in collaboration with Deltares.
For more information please visit the site http://compoundevents.org/
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