Alaska Volcano Observatory

Lava continues to slowly erupt within the summit crater at Great Sitkin Volcano. Minor lava dome growth to the southwest and rockfalls down the south side of the dome were observed in rare clear satellite views. Elevated surface temperatures from the warm, active lava dome were also observed when conditions allowed. Seismic activity remains low, with the detection of occasional small volcanic earthquakes and seismic signals from small rockfalls within the crater.   

The current lava eruption began in July 2021 and has filled most of the summit crater and advanced into the valleys below. There have been no explosions at Great Sitkin Volcano since an event in May 2021. The volcano is monitored using local seismic and infrasound sensors, satellite data, and web cameras, and regional infrasound and lightning networks.

Signs of volcanic unrest at Shishaldin Volcano continue. Seismic and infrasound activity remain elevated, with numerous small earthquakes, frequent infrasound signals, and volcanic tremor recorded throughout the week. Daytime web camera views and a high-resolution satellite view on March 19 showed minor steaming from the summit, and sulfur dioxide gas emissions were detected in satellite data all week.   

Shishaldin Volcano is monitored by local seismic and infrasound sensors, web cameras, and a telemetered geodetic network. In addition to the local monitoring network, the Alaska Volcano Observatory uses nearby geophysical networks, regional infrasound and lightning data, and satellite data to monitor the volcano. 

Low-level unrest continued at Atka volcanic complex with weak-to-moderate volcanic tremor, and numerous small earthquakes detected in seismic data. Clear satellite views over the week showed weak-to-moderately elevated surface temperatures for the Korovin summit lake region. Sulfur dioxide gas emissions were also detected in satellite data all week. 

The Atka volcanic complex is monitored by local seismic and infrasound sensors and webcam, satellite data, and regional lightning detection instruments.