The Interannual and Interdecadal Variations of Tropical Cyclone Affecting Shandong Province

Based on tropical cyclone yearbook data from 1949 to 2006, climate characteristics, such as interdecadal variation, period of tropical cyclone frequency, rainstorm and strong wind, intensity characteristics, were analyzed. Main results were as follows： tropical cyclone affecting Shanalong Province was mainly from the last ten-day of July to the last ten-day of August, and its interdecadal variation was obvious. The marked periodic variation of every 2.4 and 5 years was found according to power spectrum analysis. It showed obvious weakening tendency about tropical cyclone＇s intensity by using Kendall test. It also showed that August was the strongest month among a year for rainstorm frequency and intensity, and flood disaster was more easily to occur during this month. It was distinct for frequency＇s interdecadal variation of tropical cyclone causing rainstorm and strong wind. Marked period was existed about annual average precipitation and strong wind. At the same time, the cause of the variation was discussed.