ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Saturday, December 31, 2016, 12:36 PM AKST (Saturday, December 31, 2016, 21:36 UTC)

BOGOSLOF VOLCANO (VNUM #311300)
53°55'38" N 168°2'4" W, Summit Elevation 492 ft (150 m)
Current Volcano Alert Level: WARNING
Current Aviation Color Code: RED

Bogoslof volcano exploded last night at 22:30 AKST (07:30 UTC Dec 31). The eruption lasted approximately 45 minutes and was recorded by seismic stations on nearby islands and infrasound (pressure) sensors in Dillingham. Eruptive activity was also detected by the World Wide Lightning Location Network, which identified lightning strikes associated with the resulting volcanic plume. Following a period of brief quiescence, low-level eruptive activity began again at 05:00 AKST (14:00 UTC) as detected by the distant Dillingham infrasound array, and remains ongoing. This activity is weaker than prior explosions, including last night’s, but is relatively continuous, indicating persistent unrest. No lightning strikes have been detected coinciding with the current activity, and nothing has been observed in satellite data above the regional cloud layer (25,000 ft asl). Seismic and infrasound data at nearby islands are currently hampered by windy conditions in the region, which limits our ability to detect unrest associated with explosions.

Due to the unpredictability of the situation and potential for resumed explosive activity, the Aviation Color Code remains RED and the Volcano Alert Level WARNING.

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 nearby islands for indications of volcanic activity.


PAVLOF VOLCANO (VNUM #312030)
55°25'2" N 161°53'37" W, Summit Elevation 8261 ft (2518 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

A small steam plume from the summit was observed in web camera images, and nothing was observed in partly cloud satellite views. Nothing significant was detected in seismic or pressure sensor data during the past day.

The degree of unrest at Pavlof can change quickly. A return to eruptive activity can occur with with little or no warning.

CLEVELAND VOLCANO (VNUM #311240)
52°49'20" N 169°56'42" W, Summit Elevation 5676 ft (1730 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

No activity was observed in cloudy satellite views over the past day, and no significant activity was detected in seismic or pressure sensor data during the past 24 hours.

OTHER ALASKA VOLCANOES

Other Alaska volcanoes show no signs of significant unrest: http://www.avo.alaska.edu/activity/

AVO scientists conduct daily checks of earthquake activity at all seismically-monitored volcanoes, examine web camera and satellite images for evidence of airborne ash and elevated surface temperatures, and consult other monitoring data as needed.

For definitions of Aviation Color Codes and Volcano Alert Levels, see: http://www.avo.alaska.edu/color_codes.php

FOR MORE INFORMATION ON ALASKA VOLCANOES: http://www.avo.alaska.edu

SUBSCRIBE TO VOLCANO ALERT MESSAGES by email: http://volcanoes.usgs.gov/vns/

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CONTACT INFORMATION:

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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