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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.