TY  - JOUR
A1  - Macdonald, Elena
A1  - Merz, Bruno
A1  - Guse, Björn
A1  - Wietzke, Luzie
A1  - Ullrich, Sophie
A1  - Kemter, Matthias
A1  - Ahrens, Bodo
A1  - Vorogushyn, Sergiy
T1  - Event and catchment controls of heavy tail behavior of floods
JF  - Water resources research
N2  - In some catchments, the distribution of annual maximum streamflow shows heavy tail behavior, meaning the occurrence probability of extreme events is higher than if the upper tail decayed exponentially. Neglecting heavy tail behavior can lead to an underestimation of the likelihood of extreme floods and the associated risk. Partly contradictory results regarding the controls of heavy tail behavior exist in the literature and the knowledge is still very dispersed and limited. To better understand the drivers, we analyze the upper tail behavior and its controls for 480 catchments in Germany and Austria over a period of more than 50 years. The catchments span from quickly reacting mountain catchments to large lowland catchments, allowing for general conclusions. We compile a wide range of event and catchment characteristics and investigate their association with an indicator of the tail heaviness of flood distributions, namely the shape parameter of the GEV distribution. Following univariate analyses of these characteristics, along with an evaluation of different aggregations of event characteristics, multiple linear regression models, as well as random forests, are constructed. A novel slope indicator, which represents the relation between the return period of flood peaks and event characteristics, captures the controls of heavy tails best. Variables describing the catchment response are found to dominate the heavy tail behavior, followed by event precipitation, flood seasonality, and catchment size. The pre-event moisture state in a catchment has no relevant impact on the tail heaviness even though it does influence flood magnitudes.
KW  - heavy tail behavior
KW  - floods
KW  - event characteristics
KW  - catchment
KW  - characteristics
KW  - catchment response
Y1  - 2022
U6  - https://doi.org/10.1029/2021WR031260
SN  - 0043-1397
SN  - 1944-7973
VL  - 58
IS  - 6
PB  - American Geophysical Union
CY  - Washington
ER  -