宜昌站主汛期流量及水温变化多时间尺度分析

Multiple Time Scale Analysis of Discharge and Water Temperature Variation in Main Flood Season of Yichang Hydrologic Station

以宜昌站1956-2002年主汛期为例，采用复Morlet小波分析了流量、水温序列多时间尺度变化规律，并根据主周期预测了未来变化趋势。结果表明，主汛期流量、水温序列均存在三类时间尺度的周期，各周期尺度下小波变换系数基本为正负对应出现，呈偏丰—偏低、偏枯—偏高交替变化规律，且将持续到2015年。

Time series of discharge and water temperature in main flood season of Yichang Hydrologic Station during 1956-2002 years are analyzed with multiple time scale by using complex Morlet wavelet. Future trends of change are forecasted with the primary period. The results show that the discharge and water temperature series in main flood season has three types of time scale cycle. At different period scales, wavelet coefficients of discharge time series are positive while those of water temperature time series are negative and vice versa. The change of rules for high flow period and low water season arises alternately. And it will sustain 2015 year.