"This incident has caused a rise in sea level," a volcano observer, Wilson Wuri Wutun, said when contacted from Kupang.
According to Wutun, who was at the Ile Werung volcano post, some residents near the volcano were worried by the emission of boiling water underwater in addition to the eruption.
Based on residents' reports, the sea level increased on Sunday evening and was recorded as less than one meter while the sea inundation reached 30 meters, he said.
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"The observation station of Ile Werung volcano recorded the eruption happened on Sunday (November 28, 2021) at 9:35 p.m. local time and lasted for one hour," he informed.
The Ile Werung erupted and emitted boiling water again at 5:17 a.m. local time, he said. As of 14:59 p.m. Western Indonesian Time (WIB), the eruption was still ongoing but not significant, he added.
According to Wutun's team, based on field monitoring by observers, the emission of smoke and an explosion was witnessed one hundred meters above sea level, which was accompanied by boiling water emission at 8:29 a.m. local time.
Visually, the boiling water did not seem to be emitted by the underwater volcano in Hobal sea, Wutun said. The exact location was one kilometer south of the Hobal underwater volcano and was assessed to have the potential to influence the activity of the Ile Werung volcano complex, he added.
Wutun also asked the community surrounding Ile Werung volcano to remain alert to the impact of the eruption and emission of boiling water.
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