RESPONSE OF UPWELLING PARAMETERS TO TROPICAL CYCLONE DAHLIA IN SOUTHERN JAVA AND LAMPUNG

• Main Author: Sekaringtyas Arwiyandini, Adisti
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/77568
• Institution: Institut Teknologi Bandung

Tropical Cyclone Dahlia occurs in 27 November-4 December 2017 and moves from the southern Lampung towards the southern Java. The purpose of this study was to analyze the response of upwelling parameters: Sea Surface Temperature (SST), Mixed Layer Depth (MLD), surface salinity, chlorophyll-a, sea level anomaly, and Ekman Pumping Velocity (EPV) to Tropical Cyclone Dahlia in southern Java and Lampung waters. EPV calculations were performed using daily wind data, while SST, MLD, surface salinity, and chlorophyll-a data were anomaly. Data for all parameters are then plotted spatially. Positive EPV (upwelling occurred) at the center of cyclone from 29 November-2 December 2017 with a maximum value is 4,8 × 10-4 m/s. The sea level anomaly before the cyclone was positive due to the accumulation of water mass from western monsoon, the sea level anomaly increased positively with differen ce between during and before the cyclone is 16 cm. Before the cyclone, there was negative anomaly in southern cyclone track which was a Rossby wave. The cyclone causes the negative anomaly to be -13,4 cm lower than before. On 29 November-2 December 2017 there was a shallowing of the MLD according to the cyclone track. The MLD shallowed up to 10 m. Surface salinity increased at almost all locations with a maximum increase of 0.36 psu. At location 4 the salinity decreased by 0.18 psu because of high precipitation. Chlorophyll-a increased to 0.11 mg/m3 1 week after cyclone occured.