| (1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA) | |
| (2) Issued: | (20120619/2306Z) |
| (3) Volcano: | Cleveland (CAVW# 1101-24-) |
| (4) Current Color Code: | ORANGE |
| (5) Previous Color Code: | yellow |
| (6) Source: | Alaska Volcano Observatory |
| (7) Notice Number: | 2012/A9 |
| (8) Volcano Location: | N 52 deg 49 min W 169 deg 56 min |
| (9) Area: | Aleutians Alaska |
| (10) Summit Elevation: | 5676 ft (1730 m) |
| (11) Volcanic Activity Summary: | A pilot report, web camera image, and infrasound data indicate an ash producing explosion occurred at Cleveland Volcano today around 22:05 UTC (14:05 AKDT). The pilot report suggests the cloud height is 35,000 feet (10 km) above sea level. Infrasound data indicate the eruption is short in duration. Additional sudden explosions of blocks and ash are still possible with little warning. It is possible for associated ash clouds to exceed 20,000 feet above sea level. If a large ash-producing event occurs, seismic, infrasound, or volcanic lightning networks should detect the event and alert AVO staff. There is no real-time seismic monitoring network on Mount Cleveland so AVO is unable to track activity in real time. |
| (12) Volcanic cloud height: | Estimated at 35,000 ft |
| (13) Other volcanic cloud information: | Unknown |
| (14) Remarks: | Cleveland volcano forms the western half of Chuginadak Island, a remote and uninhabited island in the east central Aleutians. It is located about 75 km (45 mi.) west of the community of Nikolski, and 1500 km (940 mi.) southwest of Anchorage. The volcano's most recent significant eruption began in February, 2001 and it produced 3 explosive events that produced ash clouds as high as 12 km (39,000 ft) above sea level. The 2001 eruption also produced a rubbly lava flow and hot avalanche that reached the sea. The most recent minor ash emissions were observed in December 2011. |
| (15) Contacts: | John Power, Scientist-in-Charge, USGS jpower@usgs.gov (907) 786-7497 Steve McNutt, Coordinating Scientist, UAF steve@giseis.alaska.edu (907) 474-7131 |
| (16) Next Notice: | A new VONA will be issued if conditions change significantly or alert levels are modified. While a VONA is in effect, regularly scheduled updates are posted at http://www.avo.alaska.edu |
