Upwelling in the Verde Island Passage (VIP)

Verde Island Passage (VIP) is a well known biodiversity corridor and considered as the center of the center of marine shore fish biodiversity. This study was undertaken to investigate the upwelling process that occur in the VIP with focus on sub-surface processes as seen from actual survey and satellite data.  An oceanographic survey was done on March 2015 to collect current data using an Acoustic Doppler Current Profiler (ADCP) and temperature-salinity (TS) profiles using an underway Conductivity Temperature Depth (CTD) profiler. Currents and TS data showed evidence of upwelling based on sloping isotherms (cooler surface temperatures shoreward) and surface offshore and subsurface onshore currents. Analysis of MODIS chlorophyll data showed elevated chlorophyll concentrations near Verde Island and the strong east-west gradient along the VIP with the pivot point also near Verde Island. The constriction near Verde Island also forms a natural boundary dividing the VIP into east and west zones that exhibit opposite trends.  This was shown to occur with season where chlorophyll concentrations were higher (lower) in the west (east) during the peak Northeast (Southwest) monsoon months.