KODIAK - One of the largest and most active volcanoes on the Alaska Peninsula has grown increasingly restless since the start of the new year, sending up small ash plumes and experiencing increased seismic tremors.
The Alaska Volcano Observatory on Tuesday upgraded Mount Veniaminof Volcano's level of concern to yellow for activity considered higher than the normal background.
The level of concern is up from green, indicating normal activity, but is not yet to the orange level, when an eruption is expected to occur or is occurring.
Mount Veniaminof, elevation 8,223 feet, is about 300 miles southwest of the city of Kodiak. A large eruption of the volcano is not expected to effect Kodiak.
Two Alaska Peninsula villages are far closer. Chignik Lake, with a population of 113, is 27 miles northeast of the mountain and Perryville, population 106, is 22 miles southeast.
Weak seismic tremors were observed starting Jan. 1 and increased slightly over the next few days. Ash emissions were observed in images of Veniaminof taken around 9:30 a.m. Tuesday.
At around 10 a.m. Tuesday, a pilot flying at 14,000 feet noted small ash emissions from Veniaminof, said Ken Dean, acting coordinating scientist at the University of Alaska Fairbanks. Later in the day, 19 separate ash bursts were observed from Veniaminof, none of which escalated above 1,650 feet from the summit, Dean said.
The most recent reports from Perryville included constant ash emissions at around 10 a.m. Wednesday.
"Activity at this volcano has been on and off over the past year," Dean told the Kodiak Daily Mirror
There is no evidence from the seismic data collected at this time that events larger than those already observed will occur, the volcano observatory indicated. The observatory warned, however, that steam and ash emissions may continue intermittently and could pose a hazard to people and low-flying aircraft near the active cone.
The observatory monitors Veniaminof continually with a nine seismic recording devices capable of detecting small earthquakes beneath the volcano. The observatory also monitors the volcano using satellite imagery collected every four to six hours to detect changes in surface temperature, ash emission, and ash cloud movement.
Veniaminof has erupted at least 12 times in the last 200 years. The last significant eruption occurred in 1993-95.
During that period of volcanic activity, intermittent emissions of ash, steam and occasional ejection of debris occurred.
Ash fall and rumbling noises were reported in Perryville and a light dusting of ash was reported in Port Heiden about 60 miles to the northeast.
A more energetic eruption occurred in 1939, depositing several centimeters of fine ash on areas within about 52 miles of the volcano, including Perryville.
Minor explosions producing ash also occurred as recently as 2002.