摘要
基于小波变换与李氏指数(Lipschitz)的分析方法,对水文时间序列多尺度变化的突变特征进行了探讨,研究显示,小波变换与李氏指数分析方法不仅能将水文时间序列的突变点在时间域上展现出来,而且清晰地给出各种突变类型、强弱及分布.以黄河青铜峡站多年(1723～2000年)的天然年径流时间序列为例,分析表明其年径流在278年的变化中,共有10次较大的突变,平均28年出现一次,每次突变的类型和影响程度都有所不同;而其在近50年以来发生了4次突变,大约10年左右出现一次突变,且持续时间也较长,与以往相比其突变的频次和影响程度加剧.
A new method of analysis, wavelet transformation and Lipschitz-exponent,was introduced to analyze characteristics of sudden-change in hydrological time series. The new method could clearly demonstrate many kinds of characteristics of the time series:jump,situation of sudden-change,distribution and type of sudden-change. Based on the annual flow time series of 278 years(1723～2000) at Qingtongxia station of upper reach of the Yellow River,variations in multi-time scales and characteristics of sudden-change were probed,and the variant process of the sudden-change were shown in the different time scales with the new method.The results also displayed that was happened ten sudden-change from 1723,but there were four sudden-change,which persistent time and influence were more than ever before in the time series,since 1950.
出处
《水利水电技术》
CSCD
北大核心
2004年第11期1-3,共3页
Water Resources and Hydropower Engineering
基金
国家自然科学重点基金项目(50239050)
国家自然科学基金项目(50249024)和(40271027).
关键词
小波变换
李氏指数(Lipschitz)
突变特征
黄河上游
年径流
wavelet transformation
Lipschitz-exponent
characteristics of sudden-change
upper reach of Yellow River
annual flow
