Extreme Rainfall Events when Active Madden-Julian Oscillation Entering The Western Region of Indonesia (Case Study : Flood Events in Padang and Purworejo on June 2016) (original) (raw)

Indonesia's rainfall can't be separated from the influence of global climate phenomena, including Madden-Julian Oscillation (MJO). Based on previous research, the active phase of MJO has a correlation with the high intensity of rainfall. MJO caused the high intensity of rainfall with saturated water vapor submissions from the Indian Ocean. This study aims to determine the effect of MJO activity when the occurrence of extreme rainfall events that caused flooding and landslides in the Western Region of Indonesia on June 2016. The data used are daily data Real Time Multivariate MJO (RMM1 and RMM2), Pentad MJO index, and hourly precipitation data from Global satellite Mapping (GSMaP), while the software used are GrADS (spatial analysis), Matlab (temporal analysis), and Microsoft Office. The resultsshowed that rainfall intensityof flood events in Padang (00.93S & 100.33E) that occurred on June 16, is high enough since 4-23 WIB, in the range 10-21 mm/hr. Meanwhile flood events and landslides in Purworejo (07.70S & 110.00E) on June 18, also showed high rainfall intensity from 4-22 WIB, in the range 12-21 mm/hr. The intensity of rainfall is included in the category of heavy to very heavy which causing floods. But, the value of RMM1 and RMM2 were in phase 2 and 3 (Indian Ocean), It have not yet entered thewestern part of Indonesian Maritime Continent (phase 4). The pentad MJO index values also classified in the category of weak in phase 4 (0.36), so the MJO has no significant effect on the flood events in the western region of Indonesia.