Sedimentation for 2-moments microphysics models: How to make it fast, interactive, and avoid excessive size sorting.
Sedimentation for 2-moments microphysics models: How to make it fast, interactive, and avoid excessive size sorting.
French Title: Un nouveau schéma de sédimentation pour les modèles microphysiques à deux moments numériquement économique, interactif et sans accroissement excessif de la taille des particules.
Previously Published Material: Under review. Journal of Atmospheric Research.
Abstract ID#: 36808
English Abstract:
We present a new sedimentation scheme for 2-moments microphysical models that mimic Eulerian or Lagrangian
classical approaches with three major advantages. First, it is much faster and numerically efficient than
classical Eulerian/Lagrangian methods and it is easy to implement. Second, it allows the microphysical
processes to take into account the sedimenting particles during sedimentation; and vice versa. That is to
say that sedimentation and microphysical processes are computed at the same time. Third, it manages the
sedimenting fluxes of the two moments (particles number concentration and mass content) together to excessive size sorting, accordingly to a
minimum and a maximum mean mass particle size observable in nature. In contrast to currently used sedimentation approaches, these characteristics also allow
much longer time step for the microphysics model with a satisfying precision, and total conservation of both
mass and concentration of hydrometeor particles, paving the way toward the use of 2-moments microphysics
schemes within operational numerical weather prediction from regional to global scales and climate models.
classical approaches with three major advantages. First, it is much faster and numerically efficient than
classical Eulerian/Lagrangian methods and it is easy to implement. Second, it allows the microphysical
processes to take into account the sedimenting particles during sedimentation; and vice versa. That is to
say that sedimentation and microphysical processes are computed at the same time. Third, it manages the
sedimenting fluxes of the two moments (particles number concentration and mass content) together to excessive size sorting, accordingly to a
minimum and a maximum mean mass particle size observable in nature. In contrast to currently used sedimentation approaches, these characteristics also allow
much longer time step for the microphysics model with a satisfying precision, and total conservation of both
mass and concentration of hydrometeor particles, paving the way toward the use of 2-moments microphysics
schemes within operational numerical weather prediction from regional to global scales and climate models.