Mount Merapi

Merapi is Indonesia's most active volcano and its hazard is not lava but awan panas — flows of gas, ash and rock at hundreds of degrees running down the slope at tens to more than a hundred kilometres an hour. Such a flow cannot be outrun, which is why hazard management on Merapi rests on evacuating beforehand rather than responding after.

The eruptions of October and November 2010 were the largest since 1872. They killed more than three hundred people, drove some three hundred thousand from their homes, and their ash covered Borobudur and stopped air traffic over Java for several days. Afterwards the hazard zone boundaries were redrawn, and several hamlets on the southern slope were not permitted to be reoccupied.

The Yogyakarta court appoints a juru kunci of Merapi, a courtier charged with conducting the labuhan on the mountain's slope, a position that is religious and not one of disaster management. In 2010 the incumbent, Mas Penewu Surakso Hargo — widely known as Mbah Maridjan — did not leave his house at Kinahrejo when the evacuation order was issued, and died there with a number of those who were with him.

The episode set two real authorities against each other: an evacuation order from the disaster agency, and the standing of a courtier whose charge is at that place. After 2010 the court and the provincial government arrived at an arrangement stating that evacuation orders apply to everyone including holders of customary charges, and the arrangement was stated publicly. This encyclopedia records the event and the arrangement, and does not present 2010 as a case of resistance to science, because such a presentation misses that what met were two forms of obligation.