USGS Volcano Notice for Aviation - DOI-USGS-AVO-2024-07-08T19:53:30+00:00

The Alaska Volcano Observatory is lowering the Aviation Color Code to GREEN and Volcano Alert Level to NORMAL at Mount Cleveland. Sulfur dioxide gas emissions continue to be detected on local gas monitoring sensors, however, gas emission rates are now typical to average values since local monitoring began 2 years ago. Steaming from the summit, slightly elevated surface temperatures in the summit crater, and occasional local earthquakes are still seen at Mount Cleveland, but this activity represents background behavior at this highly active Aleutian volcano.

The last eruptive activity at Mount Cleveland was a short-lived explosion during the evening (local time) of June 1, 2020. Despite the current pause, the eruptive period at Mount Cleveland, dating back to 2001, remains ongoing and future explosions are likely. These have occurred without warning and typically generate small clouds of volcanic ash that are a hazard in the immediate vicinity of the volcano, though more significant ash emissions are possible.

Mount Cleveland is currently monitored with a five-station real-time seismic network. Based on past events, explosive eruptions of Cleveland may occur with little or no warning. Rapid detection of an ash-producing eruption may be possible using a combination of seismic, infrasound, lightning, and satellite data.