The Interannual and Interdecadal Variation of Tropical Cyclone Affecting Shandong Province
Based on tropical cyclone yearbook data from 1949 to 2003, the climate character istics, such as interdecadal variation, period of tropical cyclone's frequency , rainstorm and strong wind, intensity characteristics, are analyzed. Main resul ts are as follows: Tropical cyclone affecting Shandong Province is from the last tenday of July to August and its interdecadal variation obeys the Student's ttest; The marked periodic variation of every 2.4 years and 5 years is found according to power spectrum analysis. It shows obvious weakening tendency about tropical cyclone's intensity by using Kendall test. It also shows that August is the strongest month in a year for rainstorm frequency and intensity, and floo d disaster is more easily occurred during this month. It is distinct for freque ncy's interdecadal variation of tropical cyclone causing rainstormand strong wind. Marked period exists about annual average precipitation and st rong wind. At the same time, the cause of the variation is discussed.