ANALYSIS OF UPWELLING EVENT IN SOUTH OF JAVA SEA BASED ON JUVO 1 AND 2 MOORING DATA IN 2018-2019

• Main Author: Arvin Widatama, Muhammad
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/52249
• Institution: Institut Teknologi Bandung

South of Java Sea known as one of the most productive area in fisheries among other Indonesian Seas. One of many things that can affect the productivity rate in the ocean, especially in South Java Sea, is the upwelling process. With the presence of upwelling event, it can afford the mixing process in the ocean so it will vertically distribute the nutrient that needed by all creatures that lives under the water. This research will discuss about the period when upwelling happen and what factor that cause upwelling based on study about the vertical and horizontal current velocity that have been conducted during Transport Indonesian Seas, Upwelling and Mixing Physics (TRIUMPH) 2018-2019 research program. It is known that the upwelling intensity in southern of East Java show stronger water mass uplift than the one in southern of West Java. At the location of JUVO 1 mooring the strongest upwelling process was identified during fall 2019 or specifically September 2019 with vertical current velocity of 0,5 cm/s and reach 100 m of depth. Meanwhile at the location of JUVO 2 mooring the strongest upwelling event identified to be happened during summer 2019 or specifically July 2019 with the vertical current velocity of 1,5 cm/s and reach 200 m of depth. Due to average condition upwelling are mainly happened during southwest monsoon period with mean vertical velocity 0,025 ×10?3 m/s in south of East Java Sea and 0,003 ×10?3 ????/???? in south of West Java Sea. While during northeast monsoon period downwelling event will be found with mean vertical velocity ?0,015 ×10?3 ????/???? in south of East Java Sea and ?0,005 ×10?3 m/s in south of West Java Sea. However, from the data that cover from October 2018 – November 2019 shows that that there is upwelling indication that found during northeast monsoon period with vertical velocity range from 0,3 cm/s to 1,4 cm/s. During southwest monsoon period the vertical velocity range from 0,1 cm/s to 1,5 cm/s. Upwelling anomaly during northeast monsoon period 2018-2019 are remotely generated by weak El Niño and IOD+ event that can generate easterly wind during northeast monsoon period and form the upwelling event during that period. In south of West Java Sea this condition can be seen in December 2018 and February 2019 with vertical current velocity range from 0,3 to 04 cm/s. While in south of East Java Sea this condition are about constantly seen in December 2018 until late of March 2019 with vertical current velocity range from 0,3 to 1,4 cm/s.