Exceptional flood events: insights from three simulation approaches

Vortrag von Prof. Dr. Manuela Brunner

Datum: 29.02.24  Zeit: 15.15 - 16.15  Raum: ETH HG G 19.2

Exceptional floods, i.e. flood events with magnitudes or spatial extents occurring only once or twice a century, are rare by definition. Therefore, it is challenging to estimate their frequency, magnitude, and future changes. In this talk, I discuss three methods that enable us to study exceptional extreme events absent in observational records thanks to increasing sample size: stationary and non-​stationary stochastic simulation, reanalysis ensemble pooling, and single-​model initialized large ensembles. I apply these techniques to (1) study the frequency of widespread floods, (2) quantify future changes in spatial flood extents, (3) estimate the magnitude of floods happening once or twice a century, and (4) shed light on the relationship between future increases in extreme precipitation and flooding. These applications suggest that simulation approaches that substantially increase sample size provide a better picture of flood variability and help to increase our understanding of the characteristics, drivers, and changes of exceptional extreme events.