Surface Water Hydrology
The upper tail of a flood frequency distribution is always specifically concerned for flood control. However, different model selection criteria often give different optimal distributions when focus on upper tail of flood frequency distribution. In this study, with emphasis on the upper-tail behavior, 5 distribution selection criteria including 2 hypothesis tests and 3 information-based criteria are evaluated in selecting the best fitted distribution from 8 widely used distributions by using datasets from 4 Rivers. The performance of the 5 selection criteria is verified by using a composite criterion with focus on upper tail events defined in this study. This paper demonstrated an approach for optimally selecting suitable flood frequency distributions for different river basins. Results illustrate that (1) The information-based criteria perform better than hypothesis tests in most cases when the focus is on the goodness of predictions of the extreme upper tail events. (2) In order to decide on a particular distribution to fit the high flow, it would be better to use the composite criteria, in which the information-based criteria can be used first to rank the models and the results are inspected by hypothesis testing methods. In addition, if the information-based criteria and hypothesis tests provide different results, the composite criterion will be taken for final decision.
College of Environment and Plant Protection, Hainan University
Wednesday, January 4
10:30 AM – 12:30 PM