When floods are predicted only on the basis of local data, there may be unpleasant surprises. A new method makes it possible to significantly improve predictions - using international data from hydrologically similar areas.
What can we expect in the worst-case scenario? In regions with a high risk of flooding, this is an important question: what extreme events should the protective measures be designed for? Often this is answered simply by looking at history: The worst flood events of the past decades or centuries are regarded as a realistic upper limit for what can be expected in the future.
However, this can be misleading, as so-called "mega-floods" have shown in recent years. Time and again, extreme flood events occur, extraordinary outliers that were not considered possible on the basis of local data. However, a major research project carried out under the leadership of TU Wien (Vienna) has now been able to demonstrate: If one considers the entire European continent, these local surprises are no longer surprising at all. If data from other regions with similar hydrological conditions is taken into account, the extent of these "mega-floods" suddenly becomes predictable. This has drastic consequences for the way in which flood protection must be dimensioned. The results have now been presented in the journal Nature Geoscience.
Read more at Vienna University of Technology
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