The Statistical Analysis Research Of The Northwest Pacific Tropical Cyclone Path Evolution And Cause

In this thesis, using the1965-2009JTWC6h daily at the Pacific Northwest best track data for the United States of America and the National Oceanic and Atmospheric Administration issued Global SST data, analysis is made on the Northwest Pacific tropical cyclone path frequency characteristics, typical model and Its interannual and interdecadal change, research the typical field modal frequency and different Ocean SST contact. The main results are as follow:(1) The period of1965to2009, the Northwest Pacific tropical cyclone frequency changes in the presence of a typical regional characteristics, which in India ocean, the presence of a negative zone, illustrate the frequency had a tendency to decrease, in the Taiwan region has coincided with the frequency area, illustrate the frequency has increased.(2) The number of occurrences of TS in Vietnam waters decreased. The possible reasons for the summer in this area have significant upwelling of cold water upwelling, sea surface temperature, the TS generation times influence. In the Luzon Strait near the presence of a positive region, so the area for the South China Sea and the Northwest Pacific is the only deepwater through regional, Kuroshio through this area south China Sea Kuroshio perennial invasion, the warm water caused the regional sea surface temperature rise, is beneficial to the formation of TS, so this area appears by the positive coverage.(3) In the path of the three typical modes in frequency.The first mode is related to the variation of TC activity in the areas near Japan and its east. The second mode is characterized by a northeast-southwest dipole of TC occurrence anomalies along the southeast coast of China and an east-west dipole near Japan and its east. The third mode is similar to the second mode, except for the absence of the east-west dipole. These patterns are shown to be related to the decadal changes in the prevailing TC tracks.(4)The three modal time series of interannual and interdecadal variability are compared to the global sea surface temperature. So that we can find out the main path of typhoon’s key area.