Articles | Volume 374
17 Oct 2016
17 Oct 2016
Comparison of cross-validation and bootstrap aggregating for building a seasonal streamflow forecast model
Simon Schick et al.
No articles found.
Nicole Clerx, Horst Machguth, Andrew Tedstone, Nicolas Jullien, Nander Wever, Rolf Weingartner, and Ole Roessler
Meltwater runoff is one of the main contributors to mass loss on the Greenland Ice Sheet that influences global sea level rise. However, it remains unclear where meltwater runs off and what processes cause this. We measured the velocity of meltwater flow through snow on the ice sheet, which ranged from 0.17 to 12.8 m hr-1 for vertical percolation and from 1.3 to 15.1 m hr-1 for lateral flow. This is an important step towards understanding where, when and why meltwater runoff occurs on the ice sheet.
Daniel Viviroli, Anna E. Sikorska-Senoner, Guillaume Evin, Maria Staudinger, Martina Kauzlaric, Jérémy Chardon, Anne-Catherine Favre, Benoit Hingray, Gilles Nicolet, Damien Raynaud, Jan Seibert, Rolf Weingartner, and Calvin Whealton
Nat. Hazards Earth Syst. Sci. Discuss.,
Revised manuscript under review for NHESSShort summary
It is difficult to estimate the magnitude of rare to very rare floods due to a lack of sufficiently long observations. The challenge is even greater in large river basins, where precipitation patterns and precipitation amounts vary considerably over the course of an event, and floods from different parts of the basin coincide. We show that computer models can provide plausible results in this setting, and can thus inform flood risk and safety assessments for critical infrastructure.
Philipp Wanner, Noemi Buri, Kevin Wyss, Andreas Zischg, Rolf Weingartner, Jan Baumgartner, Benjamin Berger, and Christoph Wanner
Hydrol. Earth Syst. Sci. Discuss.,
Manuscript not accepted for further reviewShort summary
In this study, we quantified the glacial meltwater contribution to mountainous streams using high-resolution stable water isotope analysis. The glacial meltwater made up almost 28 % of the annual mountainous stream discharges. This high contribution demonstrates that the mountainous streamflow regimes will change in the future when the glacial meltwater contribution will disappear due to global warming posing a major challenge for hydropower energy production in mountainous regions.
Regula Muelchi, Ole Rössler, Jan Schwanbeck, Rolf Weingartner, and Olivia Martius
Hydrol. Earth Syst. Sci., 25, 3577–3594,Short summary
This study analyses changes in magnitude, frequency, and seasonality of moderate low and high flows for 93 catchments in Switzerland. In lower-lying catchments (below 1500 m a.s.l.), moderate low-flow magnitude (frequency) will decrease (increase). In Alpine catchments (above 1500 m a.s.l.), moderate low-flow magnitude (frequency) will increase (decrease). Moderate high flows tend to occur more frequent, and their magnitude increases in most catchments except some Alpine catchments.
Regula Muelchi, Ole Rössler, Jan Schwanbeck, Rolf Weingartner, and Olivia Martius
Hydrol. Earth Syst. Sci., 25, 3071–3086,Short summary
Runoff regimes in Switzerland will change significantly under climate change. Projected changes are strongly elevation dependent with earlier time of emergence and stronger changes in high-elevation catchments where snowmelt and glacier melt play an important role. The magnitude of change and the climate model agreement on the sign increase with increasing global mean temperatures and stronger emission scenarios. This amplification highlights the importance of climate change mitigation.
Peter Stucki, Moritz Bandhauer, Ulla Heikkilä, Ole Rössler, Massimiliano Zappa, Lucas Pfister, Melanie Salvisberg, Paul Froidevaux, Olivia Martius, Luca Panziera, and Stefan Brönnimann
Nat. Hazards Earth Syst. Sci., 18, 2717–2739,Short summary
A catastrophic flood south of the Alps in 1868 is assessed using documents and the earliest example of high-resolution weather simulation. Simulated weather dynamics agree well with observations and damage reports. Simulated peak water levels are biased. Low forest cover did not cause the flood, but such a paradigm was used to justify afforestation. Supported by historical methods, such numerical simulations allow weather events from past centuries to be used for modern hazard and risk analyses.
Andreas Paul Zischg, Guido Felder, Rolf Weingartner, Niall Quinn, Gemma Coxon, Jeffrey Neal, Jim Freer, and Paul Bates
Hydrol. Earth Syst. Sci., 22, 2759–2773,Short summary
We developed a model experiment and distributed different rainfall patterns over a mountain river basin. For each rainfall scenario, we computed the flood losses with a model chain. The experiment shows that flood losses vary considerably within the river basin and depend on the timing of the flood peaks from the basin's sub-catchments. Basin-specific characteristics such as the location of the main settlements within the floodplains play an additional important role in determining flood losses.
Simon Schick, Ole Rössler, and Rolf Weingartner
Hydrol. Earth Syst. Sci., 22, 929–942,Short summary
Forecasting at the seasonal timescale aims to answer questions such as the following: how much water do we have next summer? Is next winter going to be extremely cold? Constrained by computer power, earth system models (ESMs) do not resolve all environmental variables of interest. Our study tests a method to refine the output of such an ESM for streamflow forecasting in the Rhine basin. The results show that the method is able to translate skill at different spatial scales.
Daniel B. Bernet, Volker Prasuhn, and Rolf Weingartner
Nat. Hazards Earth Syst. Sci., 17, 1659–1682,Short summary
To quantify the relevance of surface water floods in Switzerland, we introduce and analyze an exhaustive set of insurance flood damage claims. First, we present a method to classify such claims and then we analyze the classified data with respect to space and time. The results reveal that just as fluvial floods are responsible for vast damage in Switzerland, so too are surface water floods. Accordingly, surface water floods should receive similar attention like fluvial floods.
P. Froidevaux, J. Schwanbeck, R. Weingartner, C. Chevalier, and O. Martius
Hydrol. Earth Syst. Sci., 19, 3903–3924,Short summary
We investigate precipitation characteristics prior to 4000 annual floods in Switzerland since 1961. The floods were preceded by heavy precipitation, but in most catchments extreme precipitation occurred only during the last 3 days prior to the flood events. Precipitation sums for earlier time periods (like e.g. 4-14 days prior to floods) were mostly average and do not correlate with the return period of the floods.
O. Rössler, P. Froidevaux, U. Börst, R. Rickli, O. Martius, and R. Weingartner
Hydrol. Earth Syst. Sci., 18, 2265–2285,
R. Weingartner, B. Schädler, and P. Hänggi
Geogr. Helv., 68, 239–248,
D. Finger, A. Hugentobler, M. Huss, A. Voinesco, H. Wernli, D. Fischer, E. Weber, P.-Y. Jeannin, M. Kauzlaric, A. Wirz, T. Vennemann, F. Hüsler, B. Schädler, and R. Weingartner
Hydrol. Earth Syst. Sci., 17, 3261–3277,
M. H. Mueller, R. Weingartner, and C. Alewell
Hydrol. Earth Syst. Sci., 17, 1661–1679,
N. Köplin, B. Schädler, D. Viviroli, and R. Weingartner
Hydrol. Earth Syst. Sci., 17, 619–635,
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In water resources management, planning at the seasonal time scale is confronted with large uncertainties. Key variables are often unknown or hard to forecast, e.g. precipitation of the next three months. In the present study, we try to highlight some aspects concerning the development of a model faced with these uncertainties. Using the example of statistical streamflow forecasts, the results of the study indicate that the forecast accuracy is improved by the combination of several models.
In water resources management, planning at the seasonal time scale is confronted with large...