西安高空大气温度变化的多时间尺度分析

Multi-time Scale Analysis of Upper Air Temperature Change in Xi'an

利用Morlet小波变换,分析了西安地区1968～ 2012年高空温度的多时间尺度变化特征,并利用Yamamoto法对突变点进行真假性检验.结果显示,西安近地面大气层温度包含多个不同时间尺度的周期变化特征,主要表现为30、10年的周期震荡;等值线趋势显示对流层中下层温度自2011年已经转入冷期,对流层顶以上处于暖期;小波变化系数的零点不一定是气候变化的突变点,对流层中下层30年时间尺度变化的地面突变点在1994年、850 hPa在2011年,对流层顶50 hPa的突变点在1992和1999年.

The variation characteristics of multiple time scales temperature in Xi＇an region from 1968 to 2012 was analyzed based on Molet wavelet transform method,and the truth and falsehood of mutation point was tested by using the method of Yamamoto.The results showed that Xi hn annual average temperature of all different levels contain many multi-time scale periodic variations and evolution characters,mainly including 30,10 a cyclical fluctuation; contour trend display the lower air temperature has turned into cold period; it will be in warm period above the tropopause ; the zero of wavelet change coefficient is not necessarily the abrupt change point of the climate change,the ground abrupt change point of the middle-lower troposphere 30 a time scale variations is in 1994,and 850 hPa is in the year of 2011,the abrupt change point of troposphere 50 hPa is in 1992 and 1999.