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Mount Semeru Erupts, Residents Evacuate Amid California Mudslides

1/4/2026

47 9 Full Breakdown

Summary

Story summary

On January 3, 2026, Mount Semeru in East Java erupted again.
The ash column reached 1,000 meters above the peak.
The Center for Volcanology and Geological Hazard Mitigation kept the alert level at III.
Residents were advised to avoid the southeast sector and stay 500 meters from riverbanks due to hot clouds.
In California, Highway 101 is closed due to mudslides and flooding.

History

Historical Context

Mount Semeru, Indonesia's highest volcano at 3,676 meters, erupted on December 4, 2021, following heavy rainfall that caused the lava dome to collapse. This eruption displaced over 10,000 people and resulted in significant damage to homes and infrastructure. Indonesia's geological activity, part of the Pacific Ring of Fire, has a history of eruptions, including notable events like Krakatoa in 1883.

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Story summary

On January 3, 2026, Mount Semeru in East Java erupted again.
The ash column reached 1,000 meters above the peak.
The Center for Volcanology and Geological Hazard Mitigation kept the alert level at III.
Residents were advised to avoid the southeast sector and stay 500 meters from riverbanks due to hot clouds.
In California, Highway 101 is closed due to mudslides and flooding.

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