近57年锡林浩特市气温与降水量变化的小波分析

The Wavelet Analysis of Average Temperature and Precipitation in Xilinhot During 57 Years

使用Morlet小波分析法,对1953～2009年锡林浩特市平均气温和平均降水量的变化特征进行分析.结果表明:不同时间尺度平均气温所反映的冷暖结果存在一定差异,在57a尺度上,平均气温主要存在50a、35a、20a和15a左右的震荡周期,在30a尺度上,平均气温主要存在23a、13a和10a左右的震荡周期;不同时间尺度平均降水量所反映的降水多少存在一定差异,在57年尺度上,平均降水量主要存在50a、40a、30a和15a左右的震荡周期,在30a尺度上,平均降水量主要存在20a和5a左右的震荡周期;水热组合表现出湿热-干热-湿热-干热-湿热-干热交替出现的规律,植被的分布情况为多-少-多-少-多-少,平均气温在波动中升高,平均降水量在波动中减少,在21世纪初期表现最明显;干燥度随时间的变化呈波动减小趋势,大致出现了2种变化形式,多以中等干旱为主,严重干旱主要发生在20世纪80年代以后,21世纪初期表现得最为明显.

Using the method of Morlet wavelet analysis to analyze the average temperature and precipitation in Xilinhot during 57 years.The results showed that at the different time scales,average temperature reflected different results.At the 57 a scales,average temperature mainly existed 50 a;35 a;20 a and 15 a fluctuation.At the 30 a scales average temperature mainly existed 20 a and 5 a fluctuation.The combination of water and heat showed that the wet-hot and dry-hot alternative changing trend.Distribution pattern of vegetation showed more-less alternative changing trend.The average temperature is increased while average precipitation is reducing.In the early 21st century,it was obvious.Aridity is reducing with time.There were generally appearing two kinds of changing forms,mainly moderate drought.After the 1980s,it is mainly severe drought.In the early 21st century,it was most obvious.