Abstract R/V MIRAI (MR01-K05 Leg3) of Japan Marine Science and Technology Center (JAMSTEC) was stationed at the point of 2° North and 138° East in the western equatorial Pacific Ocean from November 9 to December 9, 2001. During this air–sea interaction research cruise SeaWiFS and NOAA/AVHRR local area coverage (LAC) scenes were received by the station onboard R/V MIRAI and the products derived from these satellites are verified against oceanographic observations including the parameter of sea surface temperature, salinity, chlorophyll-a and current velocity profile to the depth of 300 m. Level 3 wind vector products derived from QuickSCAT onboard SeaWinds are also collected and validated against in situ wind vectors. The diurnal change of amplitude of sea surface temperature decreases from 1.5° to 0° after the week-long prevailing northwest monsoon wind with the maximum gust more than 20 m/s while the observed surface salinity and chlorophyll-a concentration increase from 34.1 to 34.37 and from 0.05 to 0.14 mg/m3, respectively. The increase of chlorophyll-a and the decrease of sea surface temperature in this region are shown in the multi-date SeaWiFS chlorophyll-a concentration products and multi-channel sea surface temperature (MCSST) products from NOAA/AVHRR. Wind vector patterns before and after the gust more than 20 m/s are also observed by QuickSCAT. During the period of the week-long northwest monsoon wind the current velocity of upper 70 m reaches about 70 cm/s in the southeastward direction while the current velocity at the depth from 80 to 120 m indicates 50 cm/s in the northwestward direction. The current of upper 70 m corresponds to the northwest monsoon current (NMC) and the intrusion of NMC enhanced by the strong northwest monsoon winds (westerly wind bursts) causes a reversal in the sub-surface current (New Guinea coastal undercurrent, NGCUC) which creates a temporal upwelling in this region.
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