The influence of global climate indices on rainfall distribution pattern and its impact on crop yield in Gunung Kidul, Yogyakarta, Indonesia.

The correlation between the global climate index (SOI/SST), rainfall distribution and crop yield in rain-fed highland areas was investigated. For this analysis, rainfall data were collected during the rainy season (OctoberMarch) for the period 1981 to 2009 in Gunung Kidul district of Yogyakarta Province, which is one of the important rain-fed crop producers in Indonesia. The rainfall distribution pattern found indicates that most of the rainfall occurs in coastal areas, especially in the southern hilly areas, where the occurrence of the Southern Oscillation Index (SOI) and Surface Sea Temperatures (SST) Nino.West are also highly correlated with rainfall. Soybean yield is highly correlated with rainfall while dry land paddies, peanuts and wetland paddies yields show a good correlation with SOI during January-February-March-April (JFMA).