Runoff Variation Rule of Yellow River Based upon Wavelet Transformation

摘要

Morlet wavelet function is used to do wavelet analysis of runoff series of Yellow River upper, middle and lower reaches. The complex structure of multi_time scales of runoff variation of Yellow River upper, middle and lower reaches are opened out. Periods of runoff series variation and points of high_water and low_water abrupt change are analyzed. Wavelet variance verification indicates that the first main periods of Yellow River upper, middle and lower reaches runoff variation are 22 years.By analyzing runoff variation trend, that Yellow River upper, middle and lower reaches will be in high_water period during about 2003～2012 is predicted. The results show that runoff variation of Yellow River upper, middle and lower reaches bear the property of synchronization.