Detection of the Abrupt Changes in Runoff Based on the Morlet Wavelet
Wavelet theory is introduced into the runoff sequence abrupt change detection in this paper. It has been proved theoretically that the Morlet wavelet coefficients of zero can be abrupt change point, and that a statistical test is carried out to determine the true point. This paper analyzes the runoff-scale varia-tion behaviors from 1961 to 2006 in the Wei River of Huaxian station, forming the center of various scales alternated with positive and negative shocks. There are three obvious changing patterns, before 1972, the average annual runoff in the Huaxian station produced the oscillation based on a 10-year cycle; from 1982 to 2001, the oscillation occurred on the basis of 7～8 year cycle. The runoff series in the 14 to 16 years cycle is very significant, with a domain-wide in Huaxian station. To identify possible mutations in the 15-year scale, Yamamoto inspection method is used to carry out the further diagnosis, and to identify the ab-rupt changes in 1972、1982 and 1994.
Morlet waveletYamamoto inspectionabrupt changeWei River
国家科技期刊平台
NSTL
万方数据
维普
