Early Investigation of Tropical Cyclones Blake-Claudia’s Effect on Seasonal Downwelling in Southern Indonesia Waters

Abstract

Abstract Indonesia southern waters area is one of the places where tropical storms form and develop into tropical cyclones. Apart from cyclones, southern Indonesia waters also experienced other oceanographic phenomena, the seasonal upwelling and downwelling. This study aims to investigate the physical conditions in southern Indonesia waters during the TC Blake-Claudia which occurred during seasonal downwelling period. Historical data shows that tropical cyclones in southern Indonesia generally occur in DFJ and almost never occur in JJA. Meanwhile, the downwelling period occurs during the DJF season. The results show TC Blake-Claudia has weaken or disrupted seasonal downwelling by decreasing SSHA and increasing chlorophyll concentration. This change in oceanographic parameter expected to be occur not only as the result of cyclonic activity which creates a void of water on the coast, but also supported by the initial conditions of the study area which tend to remain unstable just after upwelling event ends.