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Monsoonal upwelling generally occurred along the coasts of South Java to Western Sumatera. The aimed of this study was to estimate the upwelling intensity derived from sea surface temperature (SST) and chlorophyll-a. SST and chlorophyll-a data was obtained from 3 rd level of Aqua-MODIS satellite censor, and wind data derived from Quikscat satellite censor on July 2002 to June 2011. Upwelling index derived from coastal upwelling index (CUIx) formula. Statistical analysis was used to describe the relationship of SST and chlorophyll-a to CUIx. The result of this study show that the occurrence of upwelling was in east monsoon temporally, the range of SST is about 25.10 -27.30°C and chlorophyll-a is about 0.30 -0.67 mg m -3 . However in 2006 the anomaly of upwelling intensity coincide perfectly with the descend of SST to 24.98 °C (Sout Java) and 25.97 °C (West Sumatera), meanwhile the concentration of chlorophyll-a is increase to 1.3 mg m -3 (West Sumatra) and 3.71 mg m-3 (South Java). Statistical analysis show that the SST give a strong relationship between CUIx and SST (r=0.84) in West Sumatera. Meanwhile in South Java, both of those parameters (SST and Chlorophyll-a) gives the strong relationship to CUIx respectively (r= 0.86 and r = 0.81).Keywords: chlorophyll-a, coastal Upwelling Index, sea surface temperature, Western Sumatera ABSTRAKUpwelling musiman pada umumnya terjadi di sepanjang selatan jawa hingga barat sumatra. Penelitian ini bertujuan untuk mengestimasi intensitas upwelling dari data SPL dan konsentrasi klorofil-a dari sensor satelit. Data SPL dan Klorofil-a yang digunakan adalah data satelit Aqua-MODIS level-3 dan data angin dari satelit Quikscat pada bulan Juli 2002 sampai Juni 2011. Indeks upwelling diperoleh dengan formula Coastal Upwelling Index (CUIx). Analisis statistik digunakan untuk melihat hubungan antara SPL dan klorofil dengan CUIx. Hasil penelitian menunjukan bahwa secara temporal upwelling terjadi pada musim timur, dengan kisaran SPL 25.10 -27.30 °C dan konsentrasi klorofil-a 0.30 -0.67 mg m -3 . Namun pada tahun 2006 terjadi anomali intensitas upwelling yang ditandai dengan SPL yang turun mencapai 24.98 °C (Selatan Jawa) dan 25.97 °C (Barat Sumatera), konsentrasi klorofil-a meningkat 1.33 mg m -3 (Barat Sumatera) dan 3.71 mg m -3 (Selatan Jawa). Hasil analisis menunjukkan bahwa SPL memiliki hubungan yang sangat kuat dengan CUIx di Barat Sumatra (r=0.84). Sementara di perairan selatan Jawa, kedua parameter (SPL dan klorofil-a) menunjukkan hubungan yang sangat kuat dengan CUIx (r=0.86 yang untuk SPL dan r = 0.81 untuk klorofil-a).

Eastern pathway of the Indonesia Throughflow (ITF) conveys a secondary ITF inflow that brings North/South Pacific water entering interior Indonesian Seas. The transformation occurred along the Pacific water mass journey towards the Indonesian sea. For the first time since 2016, CTD Argo float measurement is available following the ITF path – along Maluku-Seram- Banda Seas, providing prime datasets to be able seen change of ITF water. This paper aims to investigate transformation of ITF water masses and the percentage of water mass contribution (with Optimum MultiParameter method) along its eastern path of ITF between Maluku – Seram and Banda Seas. The result shows that along the path, North Pacific water origin is predominant in Southern Banda Sea, but lower thermocline water of South Pacific water origin in South Maluku and Seram Sea. Large transformation of ITF water is indicated with salty upper-thermocline water in Maluku-Seram Seas, but fresh thermocline water in Banda Sea. Spatial variation of mixing layer depth and thermocline depth is also found. The percentage of the water mass contribution of the North Pacific water NPSW and NPIW gets bigger along the journey to the Banda Sea, while the dominant of SPSLTW was found in Maluku Sea and Seram Sea.

Upwelling Index which is processed from satellite imagery of wind stress and Sea Surface Temperature (SST) were examined to describe upwelling and its dynamics along the southern coast of Java. Analysis in September as the peak of upwelling shows that the commonly use of Ekman Transport-based Upwelling Index mostly shows higher values on the western part of south coast of Java as the alongshore wind stress is stronger to the west. But on the contrary, the SST-based Upwelling Index shows a relatively intense and persistent upwelling on the eastern part of south coast of Java and strengthened in El Nino year of 2015. The intense upwelling is indicated by the lowest value of SST minimum and the maximum value of thermal gradient SST up to 75 km off shore. Thus, for upwelling areas that are not predominantly induced by offshore Ekman Transport, the dynamics of upwelling would be better seen through an SST-based upwelling index. The use of both upwelling indices, will complement each other so that upwelling and its dynamics can be precisely understood.

Study on turbulent mixing processes in Labani Channel). Hal ini mengindikasikan bahwa percampuran turbulen mempunyai peran penting dalam pembentukan karakter massa air ITF.Kata kunci: percampuran turbulen, wavelet denoising, wilayah overturn, metode Thorpe, Kanal Labani, S. Makassar.