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You are here: Home > Current Volcanic Activity > Great Sitkin > ASH3D: Ash Cloud Height Model

ASH3D: Ash Cloud Height Forecast for Hypothetical Eruption
  • This ash cloud height graphic is the output of a mathematical model of volcanic ash transport in the atmosphere (Ash3D, USGS).
  • This model shows expected movement of an ash cloud 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 the height of the top of the ash cloud, in feet above sea level, as it drifts downwind.
  • 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.

During an actual eruption, see National Weather Service forecasts of airborne ash hazard to aircraft (SIGMETS: https://weather.gov/aawu/ and Volcanic Ash Advisories: https://weather.gov/vaac) as well as forecasts of ash fall: https://weather.gov/afc.
URL: avo.alaska.edu/activity/ash3d/cloud_height.php
Page modified: November 27, 2017 11:43
Contact Information: AVO Web Team

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