(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20220511/0019Z)
(3) Volcano:	Cleveland (VNUM #311240)
(4) Current Color Code:	YELLOW
(5) Previous Color Code:	UNASSIGNED
(6) Source:	Alaska Volcano Observatory
(7) Notice Number:	2022/A502
(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:	Elevated surface temperatures and sulfur dioxide emissions have been detected in satellite data over the past couple of days, representing a departure from background activity. AVO is increasing the Aviation Color Code and Volcano Alert Level from YELLOW/ADVISORY.  Cleveland volcano is monitored with a limited real-time seismic network. This smaller network inhibits AVO's ability to detect precursory unrest that may lead to an explosive eruption. Rapid detection of an ash-producing eruption may be possible using a combination of seismic, infrasound, lightning, and satellite data. Eruptions from Cleaveland 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.
(12) Volcanic cloud height:	not applicable
(13) Other volcanic cloud information:	not applicable
(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:	Michelle Coombs, Scientist-in-Charge, USGS mcoombs@usgs.gov (907) 786-7497; Tarsilo Girona, Acting Coordinating Scientist, UAFGI tarsilo.girona@alaska.edu (907) 322-4085
(16) Next Notice:

---

AVO/USGS Volcanic Activity Notice

Volcano: Cleveland (VNUM #311240)

Current Volcano Alert Level: ADVISORY
Previous Volcano Alert Level: UNASSIGNED

Current Aviation Color Code: YELLOW
Previous Aviation Color Code: UNASSIGNED

Issued: Tuesday, May 10, 2022, 4:19 PM AKDT
Source: Alaska Volcano Observatory
Notice Number: 2022/A502
Location: N 52 deg 49 min W 169 deg 56 min
Elevation: 5676 ft (1730 m)
Area: Aleutians

Volcanic Activity Summary:

Elevated surface temperatures and sulfur dioxide emissions have been detected in satellite data over the past couple of days, representing a departure from background activity. AVO is increasing the Aviation Color Code and Volcano Alert Level from YELLOW/ADVISORY. 

Cleveland volcano is monitored with a limited real-time seismic network. This smaller network inhibits AVO's ability to detect precursory unrest that may lead to an explosive eruption. Rapid detection of an ash-producing eruption may be possible using a combination of seismic, infrasound, lightning, and satellite data. Eruptions from Cleaveland 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.

Recent Observations:
[Volcanic cloud height] not applicable
[Other volcanic cloud information] not applicable

Hazard Analysis:
[Other hazards] elevated surface temperatures detected
[Volcanic gas] sulfur dioxide detected

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.

Contacts: Michelle Coombs, Scientist-in-Charge, USGS mcoombs@usgs.gov (907) 786-7497; Tarsilo Girona, Acting Coordinating Scientist, UAFGI tarsilo.girona@alaska.edu (907) 322-4085

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.

---