The water sector is one of the most important sectors to be influenced by climate change impacts, in the form of water shortage. Currently, for an example, the Java- Bali regions have already faced a deficit in its water balance. Based on climate projections, most regions in Indonesia will suffer from a gradual decrease of water supply due to temperature increase and rainfall changes that will affect the water balance. Combined with estimated population growth rates, increased water demand will cause severe water shortages to occur, especially in Java and Sumatra for the period of 2020-2030. This paper identifies several high risk regions throughout Indonesia based on the national level of climate risk study. It is found that areas which possess high risk on water shortage stretch in some parts of the Java-Bali region, especially in a few locations in the northern and southern of West Java, middle and southern of Central Java and East Java; as well as in the capital of the North Sumatra, West Sumatra, Bengkulu and Lampung (Sumatra), Nusa Tenggara Barat and South Sulawesi. This paper concludes with some possible actions to adapt to the impacts of climate change to water shortage.

The water sector is one of the most important sectors to be influenced by climate change impacts, in the form of water shortage. Currently, for an example, the Java- Bali regions have already faced a deficit in its water balance. Based on climate projections, most regions in Indonesia will suffer from a gradual decrease of water supply due to temperature increase and rainfall changes that will affect the water balance. Combined with estimated population growth rates, increased water demand will cause severe water shortages to occur, especially in Java and Sumatra for the period of 2020-2030. This paper identifies several high risk regions throughout Indonesia based on the national level of climate risk study. It is found that areas which possess high risk on water shortage stretch in some parts of the Java-Bali region, especially in a few locations in the northern and southern of West Java, middle and southern of Central Java and East Java; as well as in the capital of the North Sumatra, West Sumatra, Bengkulu and Lampung (Sumatra), Nusa Tenggara Barat and South Sulawesi. This paper concludes with some possible actions to adapt to the impacts of climate change to water shortage.