According to Bodoque, we also need to improve flood risk mapping. It is necessary to characterize vulnerability holistically, which involves considering the social, economic, physical, institutional and cultural dimensions of what makes a community vulnerable to severe weather. It is necessary to understand all the elements that increase the risk for people: not only their exposure to extreme weather conditions, but also their sensitivity and resilience. Bodoque’s own research found that most writing on vulnerability to natural disasters generally considers only two dimensions: the social and the economic, with the institutional and cultural qualities of regions being neglected.
As for the challenges of integrating the mapping of flood-prone areas into regional decision-making, Bodoque points out that there is a regulatory framework in the European Union that includes a preliminary flood risk assessment, as well as risk maps in which risks must be calculated based on the population and assets exposed. “There is still much to do; flood risk maps have a lot of uncertainty. Part of the reason, he explains, is that flooding is a random process. It is very likely that where an intense flood has already occurred, another will occur later, but it is not possible to know whether it will occur in five or 300 years.
On top of that, Bodoque explains, there is another problem. The parameters that populate the risk maps are not fixed values, but ranges: you can enter upper, middle or lower values, as you wish. However, the maps used in Spain and many other countries are deterministic; that is, they only indicate flood and non-flood areas. In other words, they only see black and white. “I provide a single map output, whereas for each of the parameters and for the range, I have infinite outputs,” explains Bodoque. Uncertainty is flattened into a deterministic map which can then generate a false sense of security.
There is a need, Bodoque says, to change this method of generating maps representing risk probabilities in flood-prone areas. This approach would better reflect the uncertainty inherent in flooding. However, this probabilistic model incurs a high computational cost.
To better cope with the risks linked to torrential rains, Bodoque underlines the importance of raising awareness among the population of the danger they face. In Spain, he and his colleagues found that people exposed to natural weather processes do not feel unsafe, in part because extreme weather events do not occur every year.
This low perception of risk has deadly consequences because it encourages reckless decisions in risky situations. On the other hand, Bodoque suggests developing communication plans for different audiences. In a article published in the Journal of Hydrology, of which he is co-author, Bodoque indicates that while “risk management based on a technocratic approach can give people a false sense of security”, the implementation of a good communication strategy on risks would facilitate a better response. to emergency alerts.
This story was originally published on WIRED in spanish and was translated from Spanish.
