The spatial distribution of a comprehensive drought risk index in Java, Indonesia

Abstract

Drought is a common hydro-meteorological disaster in several remote regions of Java, Indonesia, due to the limitation of supporting facilities in water supply management. However, little attention has been paid to drought preparedness, especially within drought risk assessment. Since Java is the most densely populated area in Indonesia and has been identified as a national food center, an effective drought risk assessment is needed for drought disaster mitigation. Therefore, a spatial drought risk assessment for the sub-district level was conducted for Java using a framework that considers the combined roles of drought hazard and drought vulnerability. Observed rainfall data from 1294 stations across Java for the time period 1991–2020 were used to define a drought hazard index. Furthermore, a drought vulnerability index was obtained by classifying several indicators that accommodated non-climate aspects. Based on these, an overall drought risk index was obtained by integrating the drought hazard index and drought vulnerability index. The results identified several areas of Java in need of priority government attention for drought disaster mitigation. Of these, the main priorities are regions with a high risk of drought, which were spread across five provinces as follows (percentage represents the number of high drought hazard index values in the sub-district to the total number of sub-districts): Yogyakarta (13.92%), West Java (7.26%), Banten (5.77%), Central Java (6.23%), and East Java (4.32%).