天津春季沙尘天气日数变化规律及小波变换特征

根据沙尘天气标准确定了1961～2003年天津逐年的春季沙尘天气日数且形成序列，分析了春季沙尘天气的演变规律，并应用小波分析方法分析了其多时间尺度的变化特征。结果表明：天津地区春季的沙尘天气以每10年-5.9天的变化速率呈显著的下降趋势；20世纪60-70年代处于沙尘多发期，90年代最少；春季沙尘天气具有40年、4～6年和16年的明显周期。t检验结果显示，气候突变大约发生在1980年前后。

Variation Regularities and Wavelet Transform Features of Dust Storms in Spring in Tianjin

The annual dust storm serials from 1961 to 2003 was established according to the Standards of Dust Storm in Spring in Tianjin, and the variation characteristics of multi-scale dust storm activities were analyzed by the wavelet analysis method. The results show that dust storms decreased significantly in the past 43 years with the change rate being - 5.9 day per ten years. Dust storms occurred more frequently in the 1960s and 1970s and less in the 1990s. It is al~ found that there are significant periods of 40 years, 4 to 6 years, 16 years in the number of dusty days in spring. The climate jump of dust storms in Tianjin is found around 1980 by t-test.