柴达木盆地近50年来年气温、降水的小波分析

采用墨西哥帽小波函数,对柴达木盆地1954-2003年近50年年气温和年降水变化时间序列进行了小波分析,揭示了柴达木盆地气温、降水变化的多时间尺度的复杂结构,分析了不同时间尺度下气温、降水序列变化的周期和突变点,并根据主周期对未来温度、降水变化进行了预测。研究表明盆地年气温变化以12年周期振荡最强,年降水变化以9年周期振荡最强。在不同时间尺度上,年气温、年降水变化具有不同的对应关系,时间尺度越小,位相差异越小。

Wavelet analysis on annual mean temperature and rainfall change of Qaidam Basin during last 50 years

The yearly average air temperature and annual precipitation data of Qaidam basin from the 1954 to 2003 were analyzed by wavelet transforms using the Mexican Hat Function.The research revealed the multi-time scale complex structure of climatic change and analyzed the periodic changes and jump features of annual mean temperature and annual precipitation series in different time scales.The results show that(1)wavelet analysis affords an effective method to analyze and process the annual mean temperature and annual precipitation data;(2) there is obvious change tendency in the annual mean temperature temporal series,but none in the annual precipitation temporal series at the confident level of 97.5 percent;(3) the strongest period-oscillation of mean temperature and precipitation variations is the 12-year and 9-year respectively;(4)in different time scales,the annual air temperature and annual rainfall change display different corresponding alternate change such as cold and hot,dry and wet etc,and the time scale is shorter,the phase difference is slighter;(5) according to the comprehensive effect of main periods and status quo,the temperature and rainfall change tendency were forecasted in future several years.(6) wavelet analysis could reveal particular structure characteristics of different time scales in time field of climatic factors provide some scientific evidence for the climatic change tendency forecast.