Seasonal Variability of Cool-core Eddy in the Western South China Sea
Received date: 2006-04-24
Revised date: 2006-09-30
Online published: 2006-11-15
In order to investigate the temporal and spatial features of the cool-core eddy in the Western South China sea, this paper analyzes the GDEM (Generalized Digital Environmental Model) hydrographic data with resolution 0.5°×0.5°. The current system in the vicinity of the cool-core eddy is determined by the P-Vector Method from the GDEM data. The results confirm the existence of the cool-core cyclonic eddy, located on the coast of South Vietnam in which upwelling occurs. The cool-core eddy shows the evident vertical layered structure (mixed layer, thermocline, and layer below the thermocline). The horizontal temperature gradient and the maximum tangential velocity of the cool-core eddy decrease with depth. The eddy center is near the coast of the Vietnam in the upper layer, and spread offshore below thermocline. The cool-core eddy displays prominent seasonal variation: The period of May and June is its developing stage during which it reaches 110.75°E and its maximum tangential velocity is 8cm/s; the period of July and August is its strongest stage during which the eddy extends to 112.50°E and its maximum tangential velocity reaches 30 cm/s, and the eddy center moves northeastward to (110.50°E, 13.25°N); during September and October, the cool-core eddy is weakening.
Key words： Cool-core eddy; P-Vector method.; Seasonal variation
LI Pi-xue , LAN Jian , HONG Jie-li . Seasonal Variability of Cool-core Eddy in the Western South China Sea[J]. Advances in Earth Science, 2006 , 21(11) : 1145 -1152 . DOI: 10.11867/j.issn.1001-8166.2006.11.1145
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