A volcano on Unimak Island in the Eastern Aleutians is on watch for an eruption — Shishaldin is spewing lava at its summit, but the real threat is if it starts to emit ash.
The Alaska Volcano Observatory detected increased activity on Shishaldin Monday — its surface temperatures had greatly elevated and the frequency of ground tremors had also increased.
According to the observatory, the U.S. Coast Guard flew over the remote volcano Wednesday to collect observations.
Cheryl Searcy is a research geophysicist for the volcano observatory. She said hazards from an eruption could affect people within 10 miles of the summit, but the closest community to Shishaldin is False Pass, 23 miles away. The main concern is if the volcano erupts ash, which can travel much further.
Searcy said ash clouds could “pose a significant hazard to aircraft and may produce ash fall on local communities such as False Pass and Cold Bay.” She said ash eruptions from Shishaldin have happened in the past and can occur with little warning. But the observatory routinely monitors the volcano using satellite and infrared data.
Shishaldin is one of the most active volcanoes in the Aleutians — it’s had nearly 30 eruptions since 1824.
Shishaldin’s most recent eruption was in 2020 when lava flowed outside the summit.