Very low level seismicity was observed over the past day with a couple small local earthquakes detected. Satellite and web camera views were mostly obscured by clouds over the past day. 

Great Sitkin Volcano is monitored by local seismic and infrasound sensors, satellite data, web cameras, and regional infrasound and lightning networks.

No unusual activity was observed in seismic or infrasound data over the past day. Steam emissions were seen in the north cone of Mount Young in a few partly cloudy web camera views this morning, but satellite views were obscured by clouds.

Although the active north cone of Mount Young continues to produce a robust steam plume when views are clear, no ash emissions or explosive activity have been detected at Semisopochnoi volcano since late January. The level of seismic activity has also decreased, with no significant seismic tremor observed since January 25th. The Alaska Volcano Observatory therefore lowered the Aviation Color Code to YELLOW and Volcano Alert Level to ADVISORY this morning.

Small eruptions producing minor ash deposits within the vicinity of the active north crater of Mount Young and ash clouds usually under 10,000 ft (3 km) above sea level have characterized the recent activity. Additional ash-producing events could occur again with little warning. 

Semisopochnoi volcano is monitored by local seismic and infrasound sensors, satellite data, web cameras, and regional infrasound and lightning networks.

Earthquake activity beneath Trident Volcano has recently increased and is ongoing, although there have been no signs of unrest in other monitoring data. Due to this increase in seismic activity to above-background levels, the Alaska Volcano Observatory raised the Aviation Color Code to YELLOW and the Volcano Alert Level to ADVISORY this morning. Over the past 24 hours, seismicity has been elevated at Trident Volcano, but no significant activity was seen in partly cloudy satellite and web camera views.

The current period of seismic unrest began on August 24, 2022. Earthquake depths at the beginning of the swarm were mostly deep, around 25 km (16 miles) below sea level, and became progressively shallower to around 5 km (3 miles) over the following four days. Since late August 2022, most earthquakes have been located in the shallow crust, with depths less than 6 km below sea level. Since January 1, 2023, earthquakes under Trident are occurring at an average rate of about ten per day. A few episodes of weak seismic tremor and low frequency earthquakes have also occurred. Increases in seismic activity have been detected previously at Trident Volcano and other similar volcanoes, with no subsequent eruptions. We expect additional shallow seismicity and other signs of unrest, such as gas emissions, elevated surface temperatures, and surface deformation to precede any future eruption, if one were to occur. 

AVO monitors Trident Volcano with a local network of seismometers, a webcam, remote sensing data, and regional infrasound and lightning networks.

Seismicity remains elevated with earthquakes detected over the past 24 hours. Satellite views of the volcano were obscured by clouds.

Takawangha volcano is monitored by local seismic and infrasound sensors, satellite data, and regional infrasound and lightning networks.