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You are here: Home > Current Volcanic Activity > Shishaldin > Ash3d Ash Fall Model

ASH3D: Ashfall Forecast for Hypothetical Eruption
  • This ashfall graphic is the output of a mathematical model of volcanic ash transport and deposition on the ground (Ash3D, USGS).
  • This model shows expected ashfall accumulation (deposit thickness) for actual or hypothetical eruptions.
  • AVO produces this graphic when a volcano is restless by assuming a reasonable hypothetical eruption, to provide a pre-eruptive forecast of areas 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.
  • Colored areas represent points of equal ash thickness on the ground. Small accumulations of ash may occur beyond the "Trace" contour. Actual deposit thickness may vary from the forecast as the modelled points are based on our best estimates. Thickness terms are explained here.
  • Hover over colored pixels to see the thickness of the ashfall deposit on the ground at any location within the model boundary.
  • The white bounding box is the model boundary and is based on an estimate of the extent of the deposit that is made before the simulation is run.
  • Options to switch between metric or English units as well as UTC or local time are in the map key.
  • To view ash cloud arrival times and duration of ashfall for communities and airports, click “View Arrival Times” in the key. Communities and airports are only listed if ashfall is expected.
  • This graphic does not show ash cloud movement in the atmosphere; please refer to the other graphics for ash cloud forecasts.
  • Report ashfall observations here.
  • For more information about ASH3D, see USGS Open-File Report 2013-1122.
  • Return to Shishaldin activity page for more information on its eruptive status.


THESE PRODUCTS MAY NOT BE CURRENT.
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.
Contact AVO Privacy Accessibility Information Quality FOIA
URL: www.avo.alaska.edu/activity/ash3d/ashfall.php
Page modified: December 21, 2022 15:07
Contact Information: AVO Web Team

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