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Luzon Strait is an important channel of communication in the western North Pacific and the South China Sea to the east side of the waters belonging to the North Pacific Subtropical Countercurrent District (the Sub Tropical Countercurrent hereafter STCC), scroll multiple of the region, the North Pacific region, after following the Kuroshio Extension the second vortex active area, this paper selected close to the the Luzon Strait of sea 120 ° E ~~ 140 ° E, 17 ° N ~~ 25 ° N as the study area, SSHA closed contour method and Okubo-Weiss parameter method kinds of vortex identification method mesoscale vortex in the region to identify and track initially obtained the spatial and temporal characteristics of mesoscale vortex in the sea and motion feature. The results showed that 36-40 vortex process average annual in the sea area of ??the study, the average duration of two months, the average mobile speed for weekly 0.6-0.7 latitude and longitude, the eddies occurrences than anticyclonic vortex process more mobile speed, the average duration is long, but the life cycle of more than three months vortex is anticyclonic. Except in the interior ocean, the sea area of ??the vortex comes mainly from the east side of the the outside Hercynian pass from mesoscale eddies, vortex terminate mainly in the east of 122 ° E latitude band, not spread across the Luzon Strait South China Sea, east of the island of Taiwan vortex terminating point-intensive areas. Vortex moving to move west of the track the main north-south offset smaller the anticyclonic vortex trajectory biased tendency South, and the longer the duration of the South biased the greater. Mesoscale eddies in the sea area between 1995-1997 and after 2003 the two time periods vortex multiple the scroll movement speed, and in that period larger and there are significant seasonal variation, while the sea area of ??the vortex activities in May for the active period of the vortex, October scroll relatively active period. Vortex high incidence of space on the sea rendering banded, north and south of 21 ° N and 22 ° N separator strip region, eddies and anticyclonic vortex vortex of the north branch of the high incidence with strong in South branch. In addition, the eastern side of Luzon Strait Kuroshio through the region, The Kuroshio flow pattern in the region is one of the hot issues of domestic and foreign research, and influenced by many other factors, has been shown Kuroshio east side in scale vortex of its existence affect the flow pattern, so try to affect the Kuroshio mean flow of vortex preliminary analysis on the basis of statistics Luzon Strait east side mesoscale vortex. The analytical method for 124 ° E ~~ 126 ° E, 20 ° N ~~ 22 ° N, the vortex occurred within the reference area as the basis, respectively, eddies and anticyclonic vortex the abnormal flow field and the average flow The field of the synthesis, and by changing the position of the reference area and the change when times involved in the synthesis of the flow field to examine the impact of the scroll position change. The results showed that the mesoscale vortex flow field structure inside and outside the bicyclic structure, the gas vortex corresponds to the center of the low water level and high water level of the external ring outward water level gradient first increases and then decreases, corresponding geostrophic flow field internal counter-clockwise rotation, external clockwise rotation, so when the eddies near the mean flow, the first North the mean flow velocity anomaly, abnormal flow rate of the gas the vortex continue to mean flow near the North to become smaller and smaller until into south velocity anomalies that eddies near the average of the process stream, the average flow rate the first progressively larger gradually smaller. The anticyclonic vortex similar, first decreases with the mean flow position from far and near, the average flow velocity increases. The vortex also affect the average stream flow increases, the gas vortex amplitude narrowing of the average stream flow, the average stream flow amplitude anticyclonic eddy wider. The above vortex average flow velocity of the linear superposition process.
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