(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20161225/0457Z)
(3) Volcano:	Bogoslof (VNUM #311300)
(4) Current Color Code:	ORANGE
(5) Previous Color Code:	RED
(6) Source:	Alaska Volcano Observatory
(7) Notice Number:
(8) Volcano Location:	N 53 deg 55 min W 168 deg 2 min
(9) Area:	Aleutians
(10) Summit Elevation:	492 ft (150 m)
(11) Volcanic Activity Summary:	No further ash emissions have occurred at Bogoslof since the explosive eruption yesterday at 09:30 AKST (18:30 UTC). Seismicity attributed to the ongoing volcanic unrest has been periodically visible on nearby island networks in the past day and a half, but levels have been generally low since the explosion yesterday. While the possibility of further ash-producing eruptions is still present, we are unable to state that such activity is imminent. We are thus lowering the Aviation Color Code to ORANGE and the Alert Level to WATCH. AVO has no ground-based volcano monitoring equipment on Bogoslof volcano. We continue to monitor satellite images, information from the Worldwide Lightning Location Network pertaining to volcanic-cloud lightning, and data from seismic and infrasound instruments on other islands for indications of volcanic activity. At present, these observations should allow timely detection of additional explosive events.
(12) Volcanic cloud height:	none detected
(13) Other volcanic cloud information:	Unknown
(14) Remarks:
(15) Contacts:	Michelle Coombs, Scientist-in-Charge, USGS mcoombs@usgs.gov (907) 786-7497 Janet Schaefer, Acting Coordinating Scientist, DGGS janet.schaefer@alaska.gov (907) 322-4085
(16) Next Notice:

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AVO/USGS Volcanic Activity Notice

Volcano: Bogoslof (VNUM #311300)

Current Volcano Alert Level: WATCH
Previous Volcano Alert Level: WARNING

Current Aviation Color Code: ORANGE
Previous Aviation Color Code: RED

Issued: Saturday, December 24, 2016, 7:57 PM AKST
Source: Alaska Volcano Observatory
Notice Number:
Location: N 53 deg 55 min W 168 deg 2 min
Elevation: 492 ft (150 m)
Area: Aleutians

Volcanic Activity Summary: No further ash emissions have occurred at Bogoslof since the explosive eruption yesterday at 09:30 AKST (18:30 UTC). Seismicity attributed to the ongoing volcanic unrest has been periodically visible on nearby island networks in the past day and a half, but levels have been generally low since the explosion yesterday. While the possibility of further ash-producing eruptions is still present, we are unable to state that such activity is imminent. We are thus lowering the Aviation Color Code to ORANGE and the Alert Level to WATCH.

AVO has no ground-based volcano monitoring equipment on Bogoslof volcano. We continue to monitor satellite images, information from the Worldwide Lightning Location Network pertaining to volcanic-cloud lightning, and data from seismic and infrasound instruments on other islands for indications of volcanic activity. At present, these observations should allow timely detection of additional explosive events.

Recent Observations:
[Volcanic cloud height] none detected
[Other volcanic cloud information] Unknown

Contacts: Michelle Coombs, Scientist-in-Charge, USGS
mcoombs@usgs.gov (907) 786-7497

Janet Schaefer, Acting Coordinating Scientist, DGGS
janet.schaefer@alaska.gov (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.

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