According to Bodoque, we also need to improve flood risk mapping. There is a need to characterize vulnerability in a holistic way, which means considering the social, economic, physical, institutional and cultural dimensions of what makes a community vulnerable to weather conditions. It is imperative to understand all the elements that boost risk for people: not only exposure to extreme weather, but also how sensitive and resistant they are to it. Bodoque’s own research has shown that most literature on disaster vulnerability tends to consider only two dimensions – social and economic – neglecting the institutional and cultural characteristics of regions.
Regarding the challenges of incorporating the mapping of flood-prone areas into regional decision-making, Bodoque points out that in the European Union there is a regulatory framework that includes a preliminary flood risk assessment, as well as hazard maps, in which the risk must be calculated according to the population and exposed assets: “There is quite a lot to improve; flood risk maps are subject to quite high uncertainty.” He explains that this is partly because flooding is a random process. It is very likely that where there has already been an intense flood, another one will occur later, but it is not known whether it will happen in five or 300 years.
In addition, as Bodoque explains, there is another issue. The parameters that feed risk maps are not fixed values, but ranges – you can provide upper, average or lower values as needed. However, the maps used in Spain and many other countries are deterministic; that is, they only indicate floodable and unfloodable areas. In other words, they only see black and white. “I provide a single cartographic result when I have infinite results for each parameter and range,” Bodoque says. Uncertainty is flattened into a deterministic map, which can then generate a false sense of security.
According to Bodoque, it is necessary to change the way maps are generated showing the probability of risk occurrence in flood-prone areas. This approach would better reflect the uncertainty inherent in flood events. However, this probabilistic model incurs high computational costs.
To better address the threats posed by bulky rains, Bodoque emphasizes the importance of making the population aware of the dangers they face. In Spain, he and his colleagues found that people exposed to natural weather processes do not notice that they are at risk, partly because extreme weather events do not occur every year.
This low risk perception has deadly consequences because it encourages rash decisions in risky situations. Therefore, Bodoque suggests developing communication plans for different audiences. In article published in the Journal of Hydrology, which he co-authored, Bodoque points out that while “risk management based on a technocratic approach may give people a false sense of security,” implementing a good risk communication strategy would facilitate a better response to emergency alerts.
This story originally appeared on WIRED in Spanish and was translated from Spanish.