"Seismic, infrasound, and satellite data over the past two weeks have shown no signs of eruptive activity at Semisopochnoi. A robust steam plume and a crater lake have been seen in clear satellite images, but no recent ash deposits.
"Although seismic activity remains above background, it does not appear to be increasing towards an eruption in the short-term. Thus, AVO is reducing the Aviation Color Code to YELLOW and the Volcano Alert Level to ADVISORY. Unrest continues. Seismic activity persists and is characterized by occasional small earthquakes and satellite data show detectable volcanic gas (sulfur dioxide) being emitted from the volcano. Explosive activity could resume with little to no warning." (AVO) [less]

A robust steam plume and a crater lake have been seen in clear satellite images, but no recent ash deposits. Although seismic activity remains above background, it does not appear to be increasing towards an eruption in the short-term.
Seismic activity persists and is characterized by occasional small earthquakes and satellite data show detectable volcanic gas (sulfur dioxide) being emitted from the volcano. Explosive activity could resume with little to no warning. [less]

The Aviation Color Code raised to Orange and the Alert Level to Watch.
No significant ash emissions have been detected, clouds cover much of the island to around 10,000 ft (3,048 m) altitude. [less]

A clear satellite image showed steam emissions from the North Cerebus crater but no evidence for eruptive deposits on the flanks.
Volcanic Alert Level remains at Level 2. [less]

"... no signs of eruptive activity or recent ash deposits at Semisopochnoi. Although seismic activity remains above background, it does not appear to be increasing towards an eruption in the short-term. Thus, AVO is reducing the Aviation Color Code to YELLOW and the Volcano Alert Level to ADVISORY.
Unrest continues. Seismic activity persists and is characterized by short bursts of volcanic tremor and earthquakes. Explosive activity could resume with little to no warning." (AVO) [less]

Additionally, the seismic station records small explosions on 16 February.
An ash plumes were not visible, though a weather cloud deck persisted between 5,000 ft-15,000 ft (1,500 m-4,600 m) altitude. Weather clouds continued to obscure views of the volcano. [less]

During 17-20 December seismicity was characterized by tremor bursts and small explosions, though cloudy weather conditions prevented visual confirmation.
Elevated seismicity was recorded on 21 December. [less]

"The event started at 00:26 AKST / 09:26 UTC and has continued with and ongoing but weaker local seismic signal. Any volcanic ash emissions are most likely low-level.
The meteorological cloud deck has been around 10,000' (3000 m) asl over Semisopochnoi and no ash signals have been detected above this height. Nothing has been detected in lightning data." (AVO) [less]

The U.S. Geological Survey Alaska Volcano Observatory (AVO) noted that weak seismicity levels continue. No eruptive activity has been detected by regional infrasound data, and no anomalous activity was observed in cloudy satellite data over the past day.

Seismicity at the volcano has decreased over the past few weeks with no observations of seismic tremor since September 15. ...mehr

AVO reported that during 31 July-6 August seismicity at the volcano remained elevated and was characterized by periods of weak, continuous tremor and discrete low-frequency earthquakes. Satellite images were mostly cloudy, though a possible steam plume was visible during 5-6 August. ...mehr

Yesterday, the Alaska Volcano Observatory raised the alert level of the volcano due to an increase in seismicity above background levels. ...mehr

AVO reports that there have been no explosions in the last day, and only two the day before. The volcano remains highly restless and explosions could resume.

The renewed eruption has continued in the last few days. Regular small explosions are occurring, but there have been no sightings of ash plumes.

A small eruption occurred at the volcano this morning (21:00 pm local time) and was detected in seismic data. The Alaska Volcano Observatory (AVO) reports: ...mehr [alles lesen]

AVO has lowered the Aviation Color Code and Alert Level to YELLOW/ADVISORY due to satellite observations and a lack of tremor lately indicating that eruptive activity has stopped. Elevated seismicity continues.