A study on an anticyclonic eddy east of M indanao
observed by an Argo profiling float
(1．Institute of Marine Environment, Ocean University of China, Oingdao 266003, China
2．Key Laboratory of Ocean Dynamic Process and Satellite Oceanography, Second Institute of Oceanography, State Oc eanic Administration, Hangzhou 310012, China )
Abstract: An anticyclonic eddy was observed by the Argo profiling float 5900224 which was deployed at 8.7°N,129.9°E in January 2003 by the China real-time Data Center.Both the trajectory and the parking— depth (1500db)velocity field estimated from the Argo float showed that there was an anticyclonic eddy iust east of M indanao coast． The anticyclonic eddy centered at about 8.7°N, 127.6°E off the continental slope. The eddy was elliptic along the slope with a diameter scale about 180km, and it was stronger during April to July and decayed during August to October in 2003. The tangential velocity of the edge at the parking depth was 11.9— 14.0cm ·S一 and the rotation period was about 40 days. The results of the Sim—pie Ocean Data Assimilation Vertion 1.4.3(S0DA V1.4.3)well support the observation by the Argo pro—filing float. The flow pattern derived from float 5900224 and the results of SODA V1.4.3 indicate that the eddy has an intermediate feature. The water masses inside the eddy are very complicated and variable. The velocity field at the parking depth estimated from float 5900224 bears little resemblance to that at surface.
Key Words:Northwest Pacific Ocean；M indanao Island；anticyclonic eddy; intermediate current；Argo profiling floa