IDENTIFIKASI WILAYAH UPWELLING BERDASARKAN VORTISITAS dan DIVERGENSI di PERAIRAN SELATAN JAWA HINGGA NUSA TENGGARA BARAT

Abstract

One of the Indonesia waters that have been identified as the location of upwelling are southern waters of Java to West Nusa Tenggara. Identification of upwelling area based on the simulation results of the HAMburg Shelf Ocean Model (HAMSOM) 3D Baroclinic showed that a stronger intensity in the southern waters of East Java in the shoutheast monsoon. The results showed that the ITF through the Lombok Strait contributes to the strengthening of the westward flow (zonal flow) off the south coast of East Java. The Strengthening of westward flows off the coast caused a shear velocity towards the southern coast of East Java. Shear velocity towards onshore caused negative vorticity and occurred the horizontally divergence zone which resulted vacancy of water masses in the surface so as to increase the intensity of upwelling. The maximum ITF was occurred in August with value 1.30 Sv and which caused westward flows to be stronger. The statistical analysis showed that the ITF transport has a strong correlation with the zonal currents in the southern waters of East Java with a correlation coefficient 0.78. The maximum vorticity was found in August with value -8.82 x 10-6 s-1 and the maximum horizontally divergence +3.60 x 10-6 s-1 .