Propensity of rivers to extreme floods: climate-landscape controls and early detection (PREDICTED)

• Applicant: Dr. Larisa Tarasova, since 10/2022
• Subject Area: Hydrogeology, Hydrology, Limnology, Urban Water Management, Water Chemistry, Integrated Water Resources Management ; Physical Geography
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 421396820

• Final Report Year: 2023

Final Report Abstract

The recent worldwide occurrence of major river floods have led citizens and scientists to wonder whether floods have changed. The project aims to ascertain whether the normal functioning of river basins (i.e., the interactions between their climates and landscapes) can generate extreme floods also when no changes of external drivers occur. It develops methods to assess this possibility which rely on metrics that can be characterized in areas where extreme events have not been observed yet and long data records are not available. In this project we have successfully developed methods to detect in an objective way the beginning of distinct rises of observed and modelled flood frequency curves (i.e., the position of flood divides) and investigated attributes of river basins that linked to their appearance. We have also successfully shown the capability of these attributes to predict the emergence of flood divides and extreme floods in German and US river basins and investigated the chance of reliable detection of flood divides with regard to the length of available observations and river flow regimes.

Publications

• The flood cooking book: ingredients and regional flavors of floods across Germany. Environmental Research Letters, 15(11), 114024.
  Merz, Ralf; Tarasova, Larisa & Basso, Stefano
  
• Transformation of Generation Processes From Small Runoff Events to Large Floods. Geophysical Research Letters, 47(22).
  Tarasova, L.; Basso, S. & Merz, R.
  
• Characterizing hydrograph recessions from satellite-derived soil moisture. Science of The Total Environment, 756, 143469.
  Basso, Stefano; Ghazanchaei, Zohreh & Tarasova, Larisa
  
• PHEV! The PHysically-based Extreme Value distribution of river flows. Environmental Research Letters, 16(12), 124065.
  Basso, S.; Botter, G.; Merz, R. & Miniussi, A.
  
• More Complex is Not Necessarily Better in Large-Scale Hydrological Modeling: A Model Complexity Experiment across the Contiguous United States. Bulletin of the American Meteorological Society, 103(8), E1947-E1967.
  Merz, Ralf; Miniussi, Arianna; Basso, Stefano; Petersen, Karl-Jonas & Tarasova, Larisa
  
• Reliable estimation of high floods: A method to select the most suitable ordinary distribution in the Metastatistical extreme value framework. Advances in Water Resources, 161, 104127.
  Mushtaq, Sumra; Miniussi, Arianna; Merz, Ralf & Basso, Stefano
  
• Understanding Heavy Tails of Flood Peak Distributions. Water Resources Research, 58(6).
  Merz, Bruno; Basso, Stefano; Fischer, Svenja; Lun, David; Blöschl, Günter; Merz, Ralf; Guse, Björn; Viglione, Alberto; Vorogushyn, Sergiy; Macdonald, Elena; Wietzke, Luzie & Schumann, Andreas
  
• Emergence of heavy tails in streamflow distributions: the role of spatial rainfall variability. Advances in Water Resources, 171, 104359.
  Wang, H.-J.; Merz, R.; Yang, S.; Tarasova, L. & Basso, S.
  
• Extreme flooding controlled by stream network organization and flow regime. Nature Geoscience, 16(4), 339-343.
  Basso, Stefano; Merz, Ralf; Tarasova, Larisa & Miniussi, Arianna
  
• Identifying discontinuities of flood frequency curves. Journal of Hydrology, 617, 128989.
  Miniussi, Arianna; Merz, Ralf; Kaule, Lisa & Basso, Stefano
  
• Inferring heavy tails of flood distributions from common discharge dynamics. Copernicus GmbH.
  Wang, Hsing-Jui; Merz, Ralf; Yang, Soohyun & Basso, Stefano
  
• Shifts in flood generation processes exacerbate regional flood anomalies in Europe. Communications Earth & Environment, 4(1).
  Tarasova, Larisa; Lun, David; Merz, Ralf; Blöschl, Günter; Basso, Stefano; Bertola, Miriam; Miniussi, Arianna; Rakovec, Oldrich; Samaniego, Luis; Thober, Stephan & Kumar, Rohini