Sulfur dioxide gas emissions were detected on local gas monitoring sensors at Mount Cleveland starting June 21 with an increase in emission rate June 24–30. Although sulfur dioxide emissions declined to background levels on July 1, moderately elevated surface temperatures and vigorous steaming at the summit of the volcano observed over the past couple of days, suggest that Cleveland is in a state of volcanic unrest prompting the Alaska Volcano Observatory to upgrade the Aviation Color Code to YELLOW and Volcano Alert Level to ADVISORY.
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.
Cleveland volcano forms the western portion of Chuginadak Island, a remote and uninhabited island in the east central Aleutians. The volcano is located about 45 miles (75 km) west of the community of Nikolski, and 940 miles (1500 km) southwest of Anchorage. The most recent significant period of eruption began in February 2001 and produced 3 explosive events that generated ash clouds as high as 39,000 ft (11.8 km) above sea level. The 2001 eruption also produced a lava flow and hot avalanche that reached the sea. Since then, Cleveland has been intermittently active producing small lava flows, often followed by explosions that generate small ash clouds generally below 20,000 ft (6 km) above sea level. These explosions also launch debris onto the slopes of the cone producing hot pyroclastic avalanches and lahars that sometimes reach the coastline.
Matt Haney, Scientist-in-Charge, USGS mhaney@usgs.gov (907) 786-7497
David Fee, Coordinating Scientist, UAFGI dfee1@alaska.edu (907) 378-5460
The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.
| (1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA) | |
| (2) Issued: | (20240705/2254Z) |
| (3) Volcano: | Cleveland (VNUM #311240) |
| (4) Current Color Code: | YELLOW |
| (5) Previous Color Code: | GREEN |
| (6) Source: | Alaska Volcano Observatory |
| (7) Notice Number: | 2024/A507 |
| (8) Volcano Location: | N 52 deg 49 min W 169 deg 56 min |
| (9) Area: | Aleutians |
| (10) Summit Elevation: | 5676 ft (1730 m) |
| (11) Volcanic Activity Summary: |
Sulfur dioxide gas emissions were detected on local gas monitoring sensors at Mount Cleveland starting June 21 with an increase in emission rate June 24–30. Although sulfur dioxide emissions declined to background levels on July 1, moderately elevated surface temperatures and vigorous steaming at the summit of the volcano observed over the past couple of days, suggest that Cleveland is in a state of volcanic unrest prompting the Alaska Volcano Observatory to upgrade the Aviation Color Code to YELLOW and Volcano Alert Level to ADVISORY. 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.
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| (12) Volcanic cloud height: | not applicable |
| (13) Other volcanic cloud information: | Sulfur dioxide gas emissions detected on local gas monitoring sensors. |
| (14) Remarks: | Cleveland volcano forms the western portion of Chuginadak Island, a remote and uninhabited island in the east central Aleutians. The volcano is located about 45 miles (75 km) west of the community of Nikolski, and 940 miles (1500 km) southwest of Anchorage. The most recent significant period of eruption began in February 2001 and produced 3 explosive events that generated ash clouds as high as 39,000 ft (11.8 km) above sea level. The 2001 eruption also produced a lava flow and hot avalanche that reached the sea. Since then, Cleveland has been intermittently active producing small lava flows, often followed by explosions that generate small ash clouds generally below 20,000 ft (6 km) above sea level. These explosions also launch debris onto the slopes of the cone producing hot pyroclastic avalanches and lahars that sometimes reach the coastline. |
| (15) Contacts: | Matt Haney, Scientist-in-Charge, USGS mhaney@usgs.gov (907) 786-7497 David Fee, Coordinating Scientist, UAFGI dfee1@alaska.edu (907) 378-5460 |
| (16) Next Notice: | |