|(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:|
|(8) Volcano Location:||N 51 deg 55 min E 179 deg 35 min|
|(10) Summit Elevation:||2625 ft (800 m)|
|(11) Volcanic Activity Summary:||High-resolution satellite data from yesterday afternoon shows no signs of eruptive activity or recent ash deposits at Semisopochnoi. Although seismic activity remains above background, it does not appear to be increasing towards an eruption in the short-term. Thus, AVO is reducing the Aviation Color Code to YELLOW and the Volcano Alert Level to ADVISORY.
Unrest continues. Seismic activity persists and is characterized by short bursts of volcanic tremor and earthquakes. Explosive activity could resume with little to no warning.
|(12) Volcanic cloud height:||n/a|
|(13) Other volcanic cloud information:||n/a|
|(14) Remarks:||Semisopochnoi is monitored with an on-island seismic network, and remotely by satellite and lightning sensors. An infrasound array on Adak Island could detect explosive emissions from Semisopochnoi with a 13 minute delay if atmospheric conditions permit.|
|(15) Contacts:||Michelle Coombs, Scientist-in-Charge, USGS
email@example.com (907) 786-7497
David Fee, Coordinating Scientist, UAFGI
firstname.lastname@example.org (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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