Method Consideration of Variation Diagnosis and Design Value Calculation of Flood Sequence in Yiluo River Basin, China
Autor: | Xiaodong Li, Wenjiang Zhang, Xixia Ma, Xinxin Li |
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Jazyk: | angličtina |
Rok vydání: | 2020 |
Předmět: |
Return period
lcsh:TD201-500 lcsh:Hydraulic engineering Series (mathematics) Flood myth Correlation coefficient Estimation theory non-stationary Geography Planning and Development Climate change Aquatic Science Biochemistry climate change lcsh:Water supply for domestic and industrial purposes lcsh:TC1-978 Statistics Simulated annealing design flood Environmental science Extreme value theory variability diagnosis Water Science and Technology |
Zdroj: | Water, Vol 12, Iss 2722, p 2722 (2020) Water Volume 12 Issue 10 |
ISSN: | 2073-4441 |
Popis: | The conventional approaches of the design flood calculation are based on the assumption that the hydrological time series is subject to the same distribution in the past, present, and future, i.e., the series should be consistent. However, the traditional methods may result in overdesign in the water conservancy project since the series has non-stationary variations due to climate change and human activities. Therefore, it is necessary to develop a new approach for frequency estimation of non-stationary time series of extreme values. This study used four kinds of mutation test methods (the linear trend correlation coefficient, Mann&ndash Kendall test, sliding t-test, and Pettitt test) to identify the trend and mutation of the annual maximum flow series (1950&ndash 2006) of three hydrological stations in the Yiluo River Basin. Then we evaluated the performance of two types of design flood methods (the time series decomposition-synthesis method, the mixed distribution model) under the impacts of climate change and human activities on hydro-meteorological conditions. The results showed that (a) the design flood value obtained by the time series decomposition-synthesis method based on the series of the backward restore is larger than that obtained by the decomposition synthesis method based on the series of the forward restore (b) when the return period is 100 years or less, the design flood value obtained by the mixed distribution model using the capacity ratio parameter estimation method is less than that obtained by the hybrid distribution model with simulated annealing parameter estimation method and (c) both methods can overcome sequence inconsistency in design frequencies. This study provides insight into the frequency estimation of non-stationary time series of extreme values under the impacts of climate change and human activities on hydro-meteorological conditions. |
Databáze: | OpenAIRE |
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