El Niño Modoki dan Dampaknya terhadap Keragaman Curah Hujan Pulau Jawa (Studi Kasus: Kabupaten Indramayu)

Abstract

Indonesian farmers are currently struggling to face drought probles in the region of rice barn, one of which is Indramayu District located int he Java Island. One of main factors of the drought is perceived that there is warm pool concentrated in the middle of Pacific Ocean the so-called El Niño Modoki. However, its impacts to Indonesia region did not much investigated yet. Hereby, it is necessary to do analysis of the impact of El Niño and El Niño Modoki on Indonesia’s rainfall variability. The study focused on rainfall over 5 areas in Indramayu District, i.e. Bondan, Indramayu, Krangkeng, Anjatan, and Cikedung. Wavelet analysis of sea surface temperature anomaly (SSTA) data Niño 3.4 and El Niño Modoki Index (EMI) along period of January 1979-December 2013 resulted differences in temporal characteristics. The composite rainfall anomalies, SSTA, anomalies of horizontal wind speed at altitude of 850hPa, and the Walker Circulation in the spatially El Niño and the El Niño Modoki years analyzed by GrADS software showed a decline trend of rainfall in the Java Islad along September-October to November (SON). Seasonal rainfall prediction model in the 5 observated areas using CPT software resulted the highest value of the principal component (PC) coefficient with high negative of EMI predictor variables in the SON season, which meant that the current El Niño Modoki caused a decline of rainfall in related season where the biggest influences occured in the Cikedung District (-0.53 ), while the PC coefficient with Niño 3.4 as variable also had high negative value in the SON season with the greatest influences occured in the Krangkeng District (-0.58).