Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.advwatres.2022.104359
Licence creative commons licence
Title (Primary) Emergence of heavy tails in streamflow distributions: the role of spatial rainfall variability
Author Wang, H.-J.; Merz, R.; Yang, S.; Tarasova, L.; Basso, S.
Journal Advances in Water Resources
Year 2023
Department ASAM; CATHYD
Volume 171
Page From art. 104359
Language englisch
Topic T5 Future Landscapes
Keywords Streamflow distributions; Spatial rainfall variability; Heavy-tails; Response time distributions; Catchment resilience; Extreme flows
Abstract Flow events with low frequency often cause severe damage, especially if their magnitudes are higher than suggested by historical observations. The heavier right tail of streamflow distribution indicates the increasing probability of high flows. In this paper, we investigate the role played by spatially variable rainfall in enhancing the tail heaviness of streamflow distributions. We synthetically generated a wide range of spatially variable rainfall inputs and fed them to a continuous probabilistic model of the catchment water transport to simulate streamflow in five German catchments with distinct properties in size and topography. Meanwhile, we used a comparable approach to analyze rainfall and runoff records from 175 German catchments. We identified the effects of spatially variable rainfall on the tails of streamflow distributions from both simulation scenarios and data analyses. Our results show that the tail of streamflow distribution becomes heavier with increasing spatial rainfall variability only beyond a certain threshold. This finding indicates the capability of catchments to buffer growing heterogeneities of rainfall, which we term catchment resilience to increasing spatial rainfall variability. The analyses suggest that the runoff routing through the river network controls this property. In fact, both small and elongated catchments are less resilient to increasing spatial rainfall variability due to their intrinsic runoff routing characteristics. We show the links between spatial rainfall characteristics and catchment geometry and the possible occurrence of high flows. The data analyses we performed on a large set of case studies confirm the simulation results and provide confidence for the transferability of these findings.
Persistent UFZ Identifier
Wang, H.-J., Merz, R., Yang, S., Tarasova, L., Basso, S. (2023):
Emergence of heavy tails in streamflow distributions: the role of spatial rainfall variability
Adv. Water Resour. 171 , art. 104359