TY  - JOUR
A1  - Merz, Bruno
A1  - Nguyen, Viet Dung
A1  - Apel, Heiko
A1  - Gerlitz, Lars
A1  - Schröter, Kai
A1  - Steirou, Eva Styliani
A1  - Vorogushyn, Sergiy
T1  - Spatial coherence of flood-rich and flood-poor periods across Germany
JF  - Journal of hydrology
N2  - Despite its societal relevance, the question whether fluctuations in flood occurrence or magnitude are coherent in space has hardly been addressed in quantitative terms. We investigate this question for Germany by analysing fluctuations in annual maximum series (AMS) values at 68 discharge gauges for the common time period 1932-2005. We find remarkable spatial coherence across Germany given its different flood regimes. For example, there is a tendency that flood-rich/-poor years in sub-catchments of the Rhine basin, which are dominated by winter floods, coincide with flood-rich/-poor years in the southern sub-catchments of the Danube basin, which have their dominant flood season in summer. Our findings indicate that coherence is caused rather by persistence in catchment wetness than by persistent periods of higher/lower event precipitation. Further, we propose to differentiate between event-type and non-event-type coherence. There are quite a number of hydrological years with considerable nonevent-type coherence, i.e. AMS values of the 68 gauges are spread out through the year but in the same magnitude range. Years with extreme flooding tend to be of event-type and non-coherent, i.e. there is at least one precipitation event that affects many catchments to various degree. Although spatial coherence is a remarkable phenomenon, and large-scale flooding across Germany can lead to severe situations, extreme magnitudes across the whole country within one event or within one year were not observed in the investigated period. (C) 2018 Elsevier B.V. All rights reserved.
KW  - Flood timing
KW  - Spatial coherence
KW  - Flood regimes
KW  - Climate variability
KW  - Catchment wetness
Y1  - 2018
U6  - https://doi.org/10.1016/j.jhydrol.2018.02.082
SN  - 0022-1694
SN  - 1879-2707
VL  - 559
SP  - 813
EP  - 826
PB  - Elsevier
CY  - Amsterdam
ER  -