A study on the temporal activities of tropical cyclone of China

The in-year and inter-year activities of tropical cyclone of China are discussed. In the light of the in-year activity of tropical cyclone, the circumference orientation is designated to the date of in-year occurring of tropical cyclone and the radius distance to its strength. By calculating the density value within the partial annulus area and drawing the isodense line, the density isogram of in-year activity of tropical cyclone can be completed. The center of the isogram indicates the date when tropical cyclone occurs most frequently in year (the frequently occurring date) and its strength (the frequently occurring value). The possibility of their occurrence is called the frequently occurring degree. In the light of the inter-year activity of tropical cyclone, activity tendency of tropical cyclone can be analysed by means of forecasting model of Markov chain that describes the law of condition transformation of natural phenomena. It can be seen that the results of the study is good and could provide some th