非一致性水文频率分析的研究进展

Advances in hydrological frequency analysis of non-stationary time series

水文频率分析计算需满足独立随机同分布假设,其中同分布是指水文样本在过去、现在和未来均服从同一总体分布,即样本应具有一致性。然而,由于气候变化及人类活动的影响,使得一致性的假设受到挑战,因此变化环境下传统频率计算方法获得的设计结果,其可靠性受到质疑。为此,探索适应非一致性极值系列的频率分析方法已显得非常重要。总结介绍国内外关于非一致性水文频率分析的一些代表性研究成果,主要集中在以下两方面:一是基于还原/还现途径;二是基于非一致性极值系列直接进行水文频率分析途径。最后对进一步值得研究的问题进行了展望。

The conventional methods of flood frequency analysis are based on the assumption that the hydrological time series is statistically independent and identically distributed. The latter assumption implies that the series is sub- ject to a same distribution in the past, present and the future, i.e. the series should be consistent. However, this as- sumption is usually not valid because of the impacts of climate change and human activities on hydro-meteorological conditions. Therefore, it is necessary to develop new approaches for frequency estimation of non-stationary time series of extreme values. The advances in the subject are presented in this study. The recent development has focused large- ly on the following two aspects, i. e. , the approach based on the backward restore or forward restore, and that directly based on the non-stationary hydro-meteorological extremes. Finally, perspectives on the hydrological frequency analy- sis of non-stationary time series are prospected.