alaska volcano observatory

Scientists have raised Pavlof Volcano's alert level, after the volcano began showing signs of restlessness. 

The Alaska Volcano Observatory issued an "advisory" for Pavlof on Monday following an ongoing tremor at the volcano, located 36 miles northeast of Cold Bay.

Scientists have downgraded the alert level at Makushin Volcano after a sustained pause in unrest. 

John Power, a geophysicist with the Alaska Volcano Observatory, said the seismicity has been steadily declining for months, following an earthquake sequence near the volcano that began in mid-June. 

Scientists have downgraded the alert level at one of Alaska's most active volcanoes after a sustained pause in volcanic unrest. 

This comes after the Alaska Volcano Observatory  raised Cleveland Volcano's alert level to "advisory" early in the summer, after a short-lived explosion on the evening of June 1.

Over the past two weeks, there has been increased earthquake activity near Makushin Volcano. The activity started on June 15 with a magnitude 4.2 earthquake, followed by several additional significant earthquakes ranging in magnitude from 3.1 to 4.1 over the next 24 hours.

These larger earthquakes have been accompanied by over 850 smaller ones located by the Alaska Volcano Observatory since mid-June. 

More than half of the City of Unalaska's tsunami sirens aren't functioning, according to city officials.

The city tested its tsunami sirens, which were purchased in 1996, on Wednesday. Three out of seven worked. 

Following a number of earthquakes near Makushin Volcano earlier in the week — which prompted the Alaska Volcano Observatory to increase the volcano's alert level to "advisory" — local concern about Unalaska's emergency preparedness has been elevated.