|(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)|
|(3) Volcano:||Semisopochnoi (VNUM #311060)|
|(4) Current Color Code:||YELLOW|
|(5) Previous Color Code:||ORANGE|
|(6) Source:||Alaska Volcano Observatory|
|(7) Notice Number:||2021/A542|
|(8) Volcano Location:||N 51 deg 55 min E 179 deg 35 min|
|(10) Summit Elevation:||2625 ft (800 m)|
|(11) Volcanic Activity Summary:||Due to a marked decline is seismicity and no evidence of explosive activity detected in satellite, seismic or infrasound data since July 12, AVO is decreasing the Aviation Color Code to YELLOW and the Alert Level to ADVISORY.
When occurring, small eruptions producing minor ash deposits within the vicinity of the active north crater of Mount Cerberus and ash clouds under 10,000 ft above sea level are typical of activity at Semisopochnoi.
|(12) Volcanic cloud height:||none|
|(13) Other volcanic cloud information:||none|
|(14) Remarks:||Semisopochnoi is monitored by a local seismic and infrasound network, local web cameras, regional lightning and infrasound sensors, and satellite data.|
|(15) Contacts:||Michelle Coombs, Scientist-in-Charge, USGS firstname.lastname@example.org (907) 786-7497
David Fee, Coordinating Scientist, UAF email@example.com (907) 322-4085
|(16) Next Notice:||A new VAN will be issued if conditions change significantly or alert levels are modified. While a VAN is in effect, regularly scheduled updates are posted at http://www.avo.alaska.edu|
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