What did drive extreme drought event in Indonesia during boreal summer/fall 2014?

Abstract

There are at least five climate-drivers influencing temporal variability of the Indonesian precipitation system, namely the diurnal cycle, the Madden-Julian Oscillation (MJO), the monsoon system, the Indian Ocean Dipole (IOD), and the El Niño–Southern Oscillation (ENSO). In particular, the IOD and the ENSO events will cause interannual variations in the Indonesian precipitation. During the positive IOD or the El Niño events, Indonesia experiences a severe drought event. On the other hand, during the negative IOD or the La Niña event, Indonesian will have excess precipitation. During 2014, most part of the Indonesian regions experience deficit precipitation leading to a severe drought event. This study is designed to evaluate the dynamics underlying the extreme climate event in 2014. Several climate indices, including the sea surface temperature (SST), outgoing long-wave radiation, and surface winds were evaluated to explain why Indonesia experience severe drought in 2014. The analysis indicates that the tropical Indo-Pacific climate modes (e.g. IOD and ENSO events) were in neutral conditions. It is, then, suggested that negative sea surface temperature anomalies in the Indonesian region, in particular in the eastern part suppressed convective activities leading to deficit precipitation over the maritime continent.