Alaska island volcano erupts, sends ash cloud to Bering Sea

A short eruption of a volcano in Alaska’s the Aleutian Islands sent an ash cloud soaring into the sky Thursday near a lightly populated area. Shishaldin Volcano erupted for about three minutes at 7:10 a.m., the Alaska Volcano Observatory announced. It produced an ash cloud that reached up to 25,000 feet (7,620 meters). The village of False Pass, with a population of 39, is on the eastern shore of the island about 22 miles (35.4 kilometres) east of Shishaldin’s summit.

The village was not affected because winds of 52 mph (84 kph) pushed the ash cloud northwest into the Bering Sea. Observers recorded a tremor that lasted for the duration of the eruption and three lightning strikes. Ongoing volcanic activity at Shishaldin already had resulted in an aviation alert watch. That level remained in effect afterwards. The National Weather Service issued an advisory about the cloud height to aircraft so they could avoid it.

Shishaldin remains at a heightened level of unrest, the observatory said, and additional explosions may occur with little warning. Shishaldin is near the centre of Unimak Island, the largest island in the Aleutian chain. The island is about 645 miles (1,038 kilometres) southwest of Anchorage. The volcano is a symmetric cone with a base diameter of about 10 miles (16 kilometres). It rises to 9,373 feet (2,857 meters).

A funnel-shaped crater at the summit is about 660 feet (200 meters) wide. It typically emits a steam plume and occasional small amounts of ash, according to the observatory. Shishaldin is one of the most active volcanoes in the Aleutians. It has had at least 54 episodes of unrest and more than 24 confirmed eruptions since 1775, according to the observatory. Most eruptions are small but an eruption in 1999 generated an ash column that reached 45,000 feet (13,716 meters).

The observatory is made up of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute and a state agency, the Alaska Division of Geological and Geophysical Surveys.