ALASKA VOLCANO OBSERVATORY WEEKLY UPDATE
U.S. Geological Survey
Friday, September 9, 2011, 2:16 PM AKDT (Friday, September 9, 2011, 22:16 UTC)

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

On September 6, AVO raised the Aviation Color Code at Cleveland to ORANGE and the Alert Level to WATCH, as a persistent thermal anomaly observed in satellite data September 3-6 indicated slow effusion of lava in the summit crater had resumed. A thermal anomaly has also been spotted over the past 24 hours, suggesting that lava-dome growth is continuing.

A growing lava dome in the crater increases the possibility of an explosive eruption, but does not necessarily indicate that one will occur. Short-lived explosions could produce ash clouds that exceed 20,000 ft above sea level. These events can occur without warning and may go undetected in satellite imagery for hours.

Without a real-time seismic network on the volcano, AVO is unable to track local earthquake activity related to volcanic unrest, provide forecasts of eruptive activity, or confirmation of explosive, ash-producing events. AVO will continue to monitor the volcano using satellite data as it becomes available.




CONTACT INFORMATION:


Chris Waythomas, Acting Scientist-in-Charge, USGS
chris@usgs.gov (907) 786-7497

Steve McNutt, Coordinating Scientist, UAF
steve@giseis.alaska.edu (907) 474-7131

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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