Redoubt – latest AVO updates 23 March 2009Posted by admin in activity reports, Alaska, eruptions, Redoubt, United States.
The latest Redoubt update from the Alaska Volcano Observatory was issued at 13:59 local time (21:59 GMT) and reports that seismicity is still elevated, ‘but has declined slightly over the past several hours’, and notes that ‘The last large explosive burst occurred at 4:31 AKDT [12:31 GMT]. There have been several smaller bursts lasting for 1-2 minutes since then. AVO has received no new reports of ash emission in the past hour’. An overflight is in progress.
A detailed statement was issued by the AVO at 12:18 local time (20:18 GMT). It reports that the eruption began at approximately 22:38 local time on 22 March: ‘Redoubt Volcano produced a series of five explosive eruptions that each lasted from four to thirty minutes. The last one ended at 5:00 AM AKDT this morning (March 23)’. Analysis of satellite imagery suggests that the ash clouds from these explosions ‘reached 60,000 ft above sea level (asl), with the bulk of the ash volume between 25 – 30,000 ft asl’. Melting of the Drift River Glacier during the eruption greatly increased water flow down the Drift River: there will be an AVO overflight today to assess conditions. At the mouth of the Drift River sits the Drift River Oil Terminal, the potential vulnerability of which has caused some concern.
A subsequent ‘Current Status Report’ issued at 12:46 local time (20:46 GMT) reports: ‘Seismic unrest remains elevated and volcanic tremor is ongoing. Since 5:00 AKDT, no ash has been visible in radar, suggesting that if ash emission is occurring, it is below approximately 13,000 ft asl and/or too fine to be detected’. The AVO warns, ‘Further explosive activity could occur with little or no warning, and could occur intermittently for weeks or months’.
The AVO’s Hut Webcam near the summit of Redoubt ceased to function during the eruption and is blacked out (the AVO’s 12:18 statement suggests this may be a telemetry failure rather than destruction of the camera), and the Cook Inlet Webcam is still showing nothing but water, mist and cloud.
For all our Redoubt coverage: Redoubt « The Volcanism Blog.
Global Volcanism Program: Redoubt – summary information for Redoubt (1103-03-)
Alaska Volcano Observatory – Redoubt – AVO information and updates for Redoubt
Alaska Volcano Observatory – main page for the AVO
Anchorage VAAC advisories – volcanic ash advisories issued by Anchorage VAAC are archived here