On The Spatial Variation Of The Relationship Between El Nino.Southern Oscillation And Indonesian Seasonal Rainfall

ABSTRACT This paper presents the results of a preliminary study on the spatial variation of relationships between Indonesian rainfall and the El Nino Southern Oscillation (ENSO) phenonrenon. It also presents the results of an examination on the spatial variation of the lag correlations between the ENSO and rainfall, with a view to establishing the SOI\u27s use in seasonal rainfall prediction. To achieve these purposes, a monthly rainfall data set covering the period of 1950-1997 for 33 synoptic stations across the region is used. The Troup Southern Oscillation Index (SOI) for the period 1949-1997 is utilized for representing the ENSO. The results confirm earlier studies about a close relationship between ENSO and Indonesian rainfall. However, it is found that there is a strong seasonality and regionalitv in the association between rainfall and SOI. Strongest relationships are observed in the southern and eastern part of the country. The results also suggest that there is possibility of seasonal rainfall prediction using previous observation of 501. Kata Kunci.: relationship - el nino southern oscillation - indonesian seasonal rainfal