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The simulations will be computed using HYSPLIT (https://www.arl.noaa.gov/hysplit/hysplit/), a model developed by the National Oceanic and Atmospheric Administration (NOAA)'s Air Resources Laboratory. The model is used for trance tracer transport and computes air parcel trajectories; it is similar to ESGlobe, which we used in Project II. Its computational approach employs a combination of the Lagrangian and Eulerian methodologies. The Lagrangian approach uses a frame of reference that moves with the air parcels and the Eulerian approach uses a fixed 3D frame of reference.
Although the eruptions contributing to the majority of ash fall lasted for 6 days, the simulations will cover the first three days of eruptions.
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