Modelling flood awareness in floodplain dynamics

Abstract

Societal awareness is a crucial factor driving floodplain dynamics. When modelling these dynamics, flood awareness decay is considered constant. However, empirical studies have shown that the intensity of an experienced event can influence awareness decay. Here we explore and model the influence of variable flood awareness decay on flood losses for two types of societies that cope with flooding by adopting structural (techno society) or nonstructural (green society) protection measures. We modified an established socio-hydrological model and performed three synthetic experiments with multiple scenarios of flood awareness decay, flood intensity, and frequency. We found that, when modelling techno societies, assuming a constant awareness decay leads to underestimating societal flood awareness after severe flood events. In contrast, overestimation of flood awareness occurs when using constant awareness decay for green societies. This might lead to overestimating the effects of human–flood dynamics, such as the levee effect and adaptation effects.