Conceptual Model Modification and the Millennium Drought of Southeastern Australia
| Autor: | Nick Potter, Robert Bridgart, Lu Zhang, Justin Hughes |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
lcsh:TD201-500
non-stationarity lcsh:Hydraulic engineering media_common.quotation_subject Geography Planning and Development drought Aquatic Science rainfall–runoff model Biochemistry Flow duration curve groundwater–surface water connection Non stationarity lcsh:Water supply for domestic and industrial purposes Goodness of fit lcsh:TC1-978 Climatology Conceptual model objective functions Environmental science Surface runoff Water Science and Technology media_common Quantile |
| Zdroj: | Water, Vol 13, Iss 669, p 669 (2021) Water Volume 13 Issue 5 |
| ISSN: | 2073-4441 |
| Popis: | Long-term droughts observed in southern Australia have changed relationships between annual rainfall and runoff and tested some of the assumptions implicit in rainfall–runoff models used in these areas. Predictive confidence across these periods is when low using the more commonly used rainfall–runoff models. Here we modified the GR4J model to better represent surface water–groundwater connection and its role in runoff generation. The modified model (GR7J) was tested in 137 catchments in south-east Australia. Models were calibrated during “wetter” periods and simulation across drought periods was assessed against observations. GR7J performed better than GR4J in evaluation during drought periods where bias was significantly lower and showed improved fit across the flow duration curve especially at low flows. The largest improvements in predictive performance were for catchments where there were larger changes in the annual rainfall–runoff relationship. The predictive performance of the GR7J model was more sensitive to objective function used than GR4J. The use of an objective function that combined daily and annual error produced a better goodness of fit when measured against 80, 50 and 20 percent excedance flow quantiles and reduced evaluation bias, especially for the GR7J model. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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