| (1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA) | |
| (2) Issued: | (20120201/0021Z) |
| (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/A2 |
| (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: | Renewed eruptive activity of Cleveland Volcano has been observed in satellite data, and AVO is raising the Aviation Color Code to Orange and the Alert Level to Watch. A new lava dome has been observed in the summit crater, and as of 30 January 2012 was approximately 40 meters (130 feet) in diameter. There have been no observations of ash emissions or explosive activity during this current lava eruption. The lava dome that formed throughout the fall-winter of 2011 was largely removed by the explosive activity on 25 and 29 December, 2011. It remains possible for intermittent, sudden explosions of blocks and ash to occur at any time, and ash clouds exceeding 20,000 feet above sea level may develop. Such explosions and their associated ash clouds may go undetected in satellite imagery for hours. If a large, explosive, ash-producing event occurs, seismic, infrasound, or volcanic lightning may be detected by local and regional monitoring networks. There is no real-time seismic monitoring network on Mount Cleveland. Additional information on Cleveland Volcano and the current activity may be found at this link: http://www.avo.alaska.edu/activity/Cleveland.php Please see http://www.avo.alaska.edu/color_codes.php for complete definitions of Aviation color codes and Volcano alert levels. |
| (12) Volcanic cloud height: | No volcanic cloud observed. |
| (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. |
| (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 |
