Harald Kling

Performance of the COSERO precipitation–runoff model under non-stationary conditions in basins with different climates

Abstract This study is a contribution to a model intercomparison experiment initiated during a workshop at the 2013 IAHS conference in Göteborg, Sweden. We present discharge simulations with the conceptual precipitation–runoff model COSERO in 11 basins located under different climates in Europe, Africa and Australia. All of the basins exhibit some form of non-stationary conditions, due, for example, to warming, droughts or land-cover change. The evaluation of the daily discharge simulations focuses on the overall model performance and its decomposition into three components measuring temporal dynamics, mean flow volume and distribution of flows. Calibration performance is similarly high as in previous COSERO applications. However, when looking at evaluation periods independent of the calibration, the model performance drops considerably, mainly due to severely biased discharge simulations in semi-arid basins with strong non-stationarity in rainfall. Simulations are more robust in European basins with humid climates. This highlights the fact that hydrological models frequently fail when simulations are required outside of calibration conditions in basins with non-stationary conditions. As a consequence, calibration periods should be sufficiently long to include both wet and dry periods, which should yield more robust predictions.

Das Wasserkraftpotenzial Österreichs im Spannungsfeld von Umweltpolitik und Klimawandel

Das theoretische Wasserkraftpotenzial Osterreichs wird auf mindestens 75000GWh/a geschatzt, wovon bereits 35300GWh/a ausgebaut sind. Vom verbleibenden Potenzial konnten ca. 18000GWh/a technisch und wirtschaftlich sinnvoll genutzt werden. Lasst man die Potenziale in hochsensiblen Gebieten (Nationalparks, Welterbestatten) unberucksichtigt, reduziert sich dieser Wert auf ca. 13000GWh/a. Gemas der osterreichischen Energiestrategie sollen von diesem Potenzial bis 2015 insgesamt 3500GWh/a durch Optimierung bestehender Anlagen oder Errichtung neuer Kraftwerke gehoben werden, was teilweise im Konflikt mit den Anforderungen der europaischen Wasserrahmenrichtlinie steht. Erzeugungseinbusen ergeben sich zukunftig moglicherweise aus Umweltauflagen und Folgen des Klimawandels.