Volcanoes Investigation and Technology Development Center (BPPTK) Yogyakarta has changed the status of Mount Merapi from “standby” to “alert” on Monday (25/10) at 06.00 am. They urged people to evacuate immediately, especially those who live in the vicinity of the river in the south-southeast sector and the southwest sector within 10 kilometers from the summit of Mount Merapi including Boyong, Kali Kuning, Gendol, Kali Woro, Kali Bebeng, Kali Krasak and Kali Bedog.
UGM disaster expert, Dr. Sudibyakto, MS, confirmed the change of status of Merapi; it is one form of early-warning system in anticipation of casualties during eruptions. "In accordance with the procedure, this alert status should be followed by all the people living around Merapi to evacuate immediately," said Sudibyakto to the reporters on Monday (25/10).
In evacuating people away from Merapi, Sudibyakto highlighted more on the need for improvements in the handling of Internally Displaced Persons as compared to that in 2006. One that needs to be addressed includes logistics distribution. In addition, the handling of trauma in children during the evacuation process needs to be done. “The children's mental condition needs to be considered especially in relation with their school activities; these should not be stopped and should run as usual," he said.
It is likely that hot clouds and ashes should come out of the Merapi eruption that can harm all agricultural products and livestocks of the community. Sudibyakto suggested that related government and community agencies pay attention to the condition.
The Geography lecturer said that the evacuation is not only aimed at avoiding casualties but raising the awareness of people who live around the Merapi. Coordination among 4 regencies including Sleman, Klaten, Magelang, and Boyolali needs to be performed continuously in terms of evacuation. "Although Magelang and Boyolali are not exposed to hot clouds, cooperation between regencies is very important," he added.
Considering the amount of Merapi’s blazing lava and lava sediment that are likely to slide down due to the increase in rainfalls, Sudibiyakto also warned the people of the possibility of lava flood. "This should be anticipated seriously because the lava deposits at the peak of Merapi amount to 10 millions cubic meters," he said.
Separately, Subandrio, said the average deformation of the body of the mountain during the “standby” status on October 21 was only 10.5 centimeters, while on October 24, it reached 42 centimeters. Material sliding down the old lava dome also increased significantly, i.e. on October 21, 2010 it was less than 100 times. But on 23 and 24 October 2010, it was recorded at 183 and 194 respectively. The measurement of deformation (swelling) of the body of the mountain was done using Electric Distance Measurement (EDM) with a reflector being installed around the peak of Merapi. "The lava has reached near the top of the mountain," Subandrio added when he was met in his office.
The data recorded on the seismograph showed that on October 22, volcanic earthquakes occurred 52 times, multiphase earthquakes (many phases) 514 times, low frequency seismic 0 time. On October 23, volcanic earthquakes occurred 80 times, seismic multi-phase earthquakes occurred 525 times and low frequency earthquakes occurred once. Meanwhile, on October 24 volcanic earthquakes occurred 80 times, 588 multiphase earthquakes and low-frequency earthquakes occurred 3 times.