Flooding is one the deadliest and most costly natural hazards on the planet. Nearly one billion people are exposed to the risk of flooding in their lifetimes with about 300 million people impacted in any given year. As a result, flooding results in major impacts on both individuals and societies, with estimated costs of 60 billion (US$) annually.
There is a clear consensus that climate change is already causing increases in the frequency and intensity of extreme rainfall events, a trend that is expected to intensify in the coming decades. As a result, it is expected that there will be a further substantial rise in flood hazard in the coming decades, with societal exposure to this risk aggravated still further as a result of population growth and the encroachment of people and infrastructure onto floodplains.
However, climate change is not the only factor influencing the evolution of flood hazard. The carrying capacity of river and delta channels to convey storm runoff without inundating adjacent floodplains is also key, yet this conveyance capacity varies through time in response to changes in roughness and due to channel re-shaping by erosion and sedimentation. Other factors such as floodplain connectivity and, in lowland rivers and deltas, changes in sea level, are also of great importance.
This session invites contributions that explore the ways in which hydrological, geomorphological, and climatic drivers interact to determine flood hazard in rivers and deltas. We also welcome studies investigating how interventions such as flood barriers, managed floodplains and hard engineering are contributing to increases or reductions in flood risk. We especially encourage interdisciplinary studies involving experimental, modelling, and field-based approaches that are advancing methods and providing new insights into: (i) how the morphodynamic functioning of fluvial systems is driving changes in recent past, present, and future trajectories of flood hazards; (ii) the effects of human-induced perturbations on flood hazard and risk; (iii) climate related impacts on future trends in flood hazard; (iv) patterns, trends and drivers of flooding and morphological changes across present and historical records.