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Eruption source parameter needs of the operational ash dispersal modelling community

^^ ^^ Samantha Engwell1, Larry Mastin2 , Lara Smale1

  • Affiliations: 1British Geological Survey, The Lyell Centre, Edinburgh, UK; 2U.S. Geological Survey, Volcano Science Center, Vancouver, Washington USA 

  • Presentation type: Poster

  • Presentation time: Thursday 16:30 - 18:30, Room Poster Hall

  • Poster Board Number: 272

  • Programme No: 6.4.18

  • Theme 6 > Session 4

Abstract

Eruption Source Parameters (ESPs) are crucial for characterising volcanic eruptions and are essential inputs to numerical models used for hazard assessment. Key ESPs for simulating ash dispersal associated with explosive volcanic eruptions include eruption plume height, mass eruption rate, eruption duration and grain-size distribution. ESPs may be estimated from ground or satellite observations, or, where observations are not available, from studies of previous eruptions or eruptions from analogous volcanoes, with additional insight provided by analysis of unrest signals. Ash dispersal modelling in an operational context, e.g. ash cloud forecasting by Volcanic Ash Advisory Centres (VAACs), requires ESPs that can approximate eruption conditions well enough for outputs to be useful for decision making. Currently, ash dispersion forecasts are communicated as 2D plots of forecast ash dispersion. However, improved computational efficiencies and recent changes to VAAC operational procedures mean that these plots will be replaced by 4D probabilistic products. The modelling approaches to produce these new products require more complex input parameter information than is currently available. To better understand these input requirements, we conducted a survey of the VAACs to detail the type and format of ESPs used in the numerical modelling approaches. While there are some differences in the specific approaches and needs of the different VAACs, survey results highlight an increasing need for uncertainty information on ESPs. This presentation will highlight key results from the survey with the aim to inform the volcanic community so that improved ESPs can be developed for operational forecasting.