ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Tuesday, May 30, 2017, 1:17 PM AKDT (Tuesday, May 30, 2017, 21:17 UTC)

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

Unrest continues at Bogoslof volcano. No detectable activity has been observed in data from seismic or infrasound stations located on nearby Islands. Sulfur dioxide gas from the eruption on May 28 continues to be observed in satellite data, with one region of detected gas located near the border between Alaska and the Yukon Territory of Canada and another over the northern Bering Strait. No new activity observed at the volcano in satellite data.

Bogoslof volcano remains at a heightened state of unrest and in an unpredictable condition. Activity may ramp back up with additional explosions producing high-altitude (>15,000 ft) volcanic clouds with little precursory activity. Some previous explosions have been preceded by an increase in earthquake activity that allowed for short-term forecasts of imminent significant explosive activity. Although we are able to detect energetic explosive activity in real-time, there is typically a lag of tens of minutes until we can characterize the magnitude of the event and the altitude of the volcanic cloud. It is possible for low-level unrest, including explosive activity, to occur that we are unable to detect with existing data sources. Such low-level periods of unrest and possible explosions could pose a hazard in the immediate vicinity of the volcano.

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.

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

No significant activity was observed in cloudy satellite images and no activity was detected in seismic or infrasound data during the past day. The summit of Cleveland Volcano has been obscured by cloud cover in web camera views over the past day.

Cleveland volcano is monitored with a limited real-time seismic network, which inhibits AVO's ability to detect precursory unrest that may lead to an explosive eruption. Rapid detection of an ash-producing eruption may be possible using a combination of seismic, infrasound, lightning, and satellite data.

OTHER ALASKA VOLCANOES

Information on all Alaska volcanoes is available at : http://www.avo.alaska.edu.

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

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

Jeff Freymueller, Coordinating Scientist, UAFGI
jfreymueller@alaska.edu (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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