DEVELOPMENT OF WARNING CRITERIA FOR LAHAR FLOW DISASTER IN GENDOL RIVER AREA OF MOUNT MERAPI
Abstract: The eruption of
Mount Merapi in 2010 leads to the lahar flow disaster in the region of the
mountain slopes. Due to the impact caused by the lahar flow, it is important to
develop warning criteria for lahar flow disaster with a simple method
corresponding to the limitation of existing data and parameters. One of the
methods is by analyzing rainfall data to predict the occurrence of lahar flow
in Gendol River. It applies the setting of standard rainfall for warning and
evacuation of sediment disasters based on Guidelines for the Development of
Warning and Evacuation System against Sediment Disasters in Developing
Countries, published by the Ministry of Land, Infrastructure, and Transport
(MLIT) Infrastructure Development Institute - Japan, 2004. This study analyzed
the critical line (CL) which can be used to predict the occurrence of lahar
flow based on the rain characteristics namely working rainfall and rainfall
intensity. Furthermore, it can be established by warning line (WL) and the
evacuation line (EL) as a basis for determining the standard rainfall for
warning (R1) and standard rainfall for evacuation (R2). The value of R1
obtained ± 6 mm and R2 ± 29 mm. The value of R1 and R2 are strongly influenced
by the availability of rainfall data and occurrence of lahar flow. The results
of this research were expected to be used as input for the warning criteria
development of early warning system lahar flow disaster on the slopes of Mount
Merapi, particularly in the area of Gendol River.
Author: Ernowo Ary
Fibriyantoro
Journal Code: jptsipilgg150040
