Alaska Volcano Observatory
ASH3D: Ash Cloud Load Forecast for Hypothetical Eruption
- This ash cloud load graphic is the output of a mathematical model of volcanic ash transport in the atmosphere (Ash3D, USGS).
- This model shows expected load (amount) of ash in the atmosphere for actual or hypothetical eruptions.
- AVO produces this graphic when a volcano is restless by assuming a reasonable hypothetical eruption, in order to provide a pre-eruptive forecast of airspace likely to be affected. During an eruption, AVO updates the forecast with actual observations (eruption start time and duration, plume height) as they become available.
- Colors represent amounts of ash in the atmosphere, summed from the bottom to the top of the cloud. Warmer colors represent areas of greater ash; colder colors mean less ash.
- Hover over the colored pixels to see the amount of ash in g/m2 of ash at any location within the model boundary (white box).
- The white bounding box is the model boundary and is based on an estimate of the extent of the cloud before the model is run.
- To view ash cloud arrival times and duration overhead for communities and airports, click “View Arrival Times” in the key. Communities and airports are only listed if an ash cloud is expected overhead.
- This graphic does not show ashfall deposition on the ground; go here for ashfall graphic. Note that it is possible for ash clouds to move overhead with little or no fallout on the ground.
- For more information about ASH3D, see USGS Open-File Report 2013-1122.
- Return to Great Sitkin activity page for more information on its eruptive status.
Page modified: December 21, 2022 15:07
Contact Information: AVO Web Team
This website is supported by the U.S. Geological Survey under Cooperative Agreement Grant G22AC00137
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