Exploring the role of risk perception in influencing flood losses over time

Abstract

<p class="Abstract"><span lang="EN-GB">What implications do societies’ risk perceptions have for flood losses? This study uses a stylized, socio-hydrological model to simulate the mutual feedbacks between human societies and flood events. It integrates hydrological modelling with cultural theory and proposes four ideal types of society that reflect existing dominant risk perception and management: risk neglecting, risk monitoring, risk downplaying and risk controlling societies. We explore the consequent trajectories of flood risk generated by the interactions between floods and people for these ideal types of society over time. Results suggest that flood losses are substantially reduced when awareness raising attitudes are promoted through inclusive, participatory approaches in the community. In contrast, societies that rely on top-down hierarchies and structural measures to protect settlements on floodplains may still suffer significant losses during extreme events. This study illustrates how predictions formed through social science theories can be applied and tested in hydrological modelling. </span></p>

Socio-hydrological aspects of floods in commercial areas in two Brazilian basins

“…The Gregorio basin has faced several flood events since urbanization started and few measures have been done to increase people's awareness and preparedness against extreme events. In the real world there are a mixture of the 4 ideal types of societies of Ridolfi (2020). Figure 5 shows the distribution of the interviewers into four clusters, 1 and 2 having more representativeness followed by 3 and 4 respectively.…”

“…The causes and implications of floods for local traders were investigated, and the type of society was classified according to Ridolfi, Albrecht, and Di Baldassarre (2020) through on-site observations and data provided by volunteers. The study, which also involved the application of a questionnaire that collected information on flood perception from traders, is of great importance, since the literature lacks research on this issue in the region.…”

“…In order to classify the study area in one of the ideal types of society proposed by Ridolfi, Albrecht, and Di Baldassarre (2020), we performed a cluster analysis using K-means method to create groups and better study the population, it is one of the most popular, simple and fast algorithms for cluster head selection (Purnima and Arvind 2014). The number of groups was defined based on the Elbow method, it is used to determine the best number of clusters by checking the percentage of the comparison of the number of clusters that will form an elbow .…”

“…risk downplaying, they underestimate environmental risk and do not see the need for collective actions; and iv. risk controlling, this society relies in protective measures system increasing its height after extreme events (Ridolfi et. al., 2020).…”

“…It has been said that societies that rely on top-down hierarchies and structural measures as protection against flood, may still suffer high losses in extreme events. Meanwhile societies that invest in increasing awareness through inclusive and participatory approaches have flood losses reduced (Ridolfi, et. al., 2020).…”