East Nusa Tenggara Underwater Volcano Triggers One-Meter Tsunami

TEMPO.CO, Jakarta - A one-meter tsunami was detected in the area of Lembata, East Nusa Tenggara, on Sunday evening of November 28, which according to the Center for Volcanology and Geological Hazard Mitigation (PVMBG) was caused by an underwater volcano in the nearby ocean. 

Volcanic activities are constantly detected to this day but have yet to show any significant increase. PVMBG head of geology Andini in a statement today said local residents reported water levels had increased by one meter and reached 30 meters into the mainland.

The volcanic eruption is specifically from the Watirar volcanic crater, which is part of the larger Ile Werung volcano complex located just one kilometer from the Hobal Volcano that erupted in 1973.

“Considering that this eruption is a manifestation of the Ile Werung volcano, activities have been increased from Level 1 or normal to Level 2 or alert starting from November 29,” said Andini. 

The local observatory station recorded the first eruption on Sunday evening lasted for roughly one hour at 21:25 WITA and recurred at dawn at 05:17. The first wave of tsunami reportedly reached one meter and traveled 30 meters into the mainland following the first eruption. 

Smoke over the submarine volcanic eruption was still visible in observations on Monday morning and reached 100 meters above sea level.

The sub-coordinator of Eastern Volcano Disaster Mitigation, Geological Agency, Devy Kamili Syahbana, confirmed that Sunday night's tsunami was triggered by a volcanic eruption, and that the one-meter tsunami was considered  shallow. There was no sea level rise in observations on Monday morning.

The tsunami potential due to the eruptions of the Ile Werung volcanic complex is the second highest in the country. "This is the most frequent. The second after the Child of Krakatau," Devy said. 

Read: Indonesian Authority Reinforces Tsunami Mitigation Capacity in Southern Java 

AHMAD FIKRI (CONTRIBUTOR)