The results of the study above are summarized as follows.

(1) Three distinctive layered current structures in the western equatorial Pacific Ocean namely the Northwest Monsoon Current (NMC) with high temperature (29.2 to 29.8℃) and low salinity (34.1 to 34.4 psu), the New Guinea Coastal Undercurrent (NGCUC) with moderate temperature (25 to 29℃) and high salinity (34.6 to 35.4 psu), the Equatorial Undercurrent (EUC) with low temperature (13 to 20℃) and high salinity (34.6 to 35.2 psu) are identified based on the temporal distribution of temperature and salinity from CTD and the velocity vectors from ADCP.

(2) The characteristics response of the upper oceanographic structure to the westerly wind bursts (instantaneous wind speed more than 20 m/sec) is found out as the Pacific Equatorial Monsoon Jet (PEMJ) reaching more than 60 cm/sec at the surface and extends to the depth of 70 m from November 20-21.

(3) The intrusion of the Northwest Monsoon Current (NMC) enhanced by the strong northwest monsoon winds (westerly wind bursts) causes a reversal in the subsurface current (New Guinea Coastal Undercurrent (NGCUC)) which creates a temporal upwelling in this region.

(4) A temporal upwelling is revealed by the sharp increase of in situ chlorophyll-a concentration, salinity and the decrease of sea surface temperature from November 19-22.

(5) The upwelling event above is supported by the multi-date SeaWiFS chlorophyll-a concentration composites. The high concentration area extends to 4°N and the northern coast of New Guinia Island.

　

Though the SeaWiFS-derived chlorophyll-a concentration products revealed the average spatial extent of the wind-induced upwelling, the investigation for the temporal characteristics of upwelling is still hindered by the high cloud coverage of SeaWiFS data. A synthetic use with a passive microwave sensor like AMSR-E onboard the Aqua satellite is recommended for sea surface temperature analysis. Furthermore the SeaWiFS-derived chlorophyll-a concentration products showed an interleaving pattern east of the stationary observation point (2N, 138E), which may indicate the anomalous pattern of wind vectors like westerly wind bursts and associated air-sea interactions in this region. Combined uses of satellite scatterometer and altimeter for detecting sea surface winds and sea surface currents such as SeaWinds on QuikSCAT and Jason-1, a follow-on altimeter of TOPEX/Poseidon are recommended.

　

　

The authors would like to acknowledge Captain Akamine and the crews of R/V MIRAI during the research cruise MR01-K05 Leg3. The authors wish to acknowledge Dr. Asanuma of NASDA/EORC for SeaWiFS data acquisition, Mr. Hanyu and his colleagues of Global Ocean Development Inc. for assisting various shipboard observations including SeaWiFS and ADCP data. The authors also wish to acknowledge Mr. Komai and his colleagues of Marine Works Japan Ltd. for their skillful in situ sampling and analysis of chlorophyll-a. All SeaWiFS LAC scenes are received by the station onboard R/V MIRAI under the authorization of NASA SeaWiFS project as the temporary real-time agreement. All SeaWiFS raw data are decrypted by using the OGP software provided by NASA GSFC. Higher-level products such as chlorophyll-a concentration are generated by using the SeaDAS software.

　

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