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Damping Characteristics of Horizontal Laplacian Diffusion Filters
Publisher: American Meteorological Society
Abstract: AbstractHorizontally diffusive computational damping terms are frequently employed in 3D atmospheric simulation models to enhance stability and to suppress small-scale noise. In configuring these filters, it is desirable ...
A Study of the Tornadic Region within a Supercell Thunderstorm
Publisher: American Meteorological Society
Abstract: The transition of a supercell thunderstorm into its tornadic phase is investigated through high-resolution numerical cloud model simulations initiated within the interior portion of a previously simulated mature supercell ...
An Isolated Cumulonimbus Observed in Northeastern Colorado: Comparison of Field Observations with Results of a Three-Dimensional Simulation
Publisher: American Meteorological Society
Abstract: Observations are described of a small, isolated cumulonimbus developing in a wind field with relatively little directional shear. The storm displayed a high degree of symmetry about a vertical plane through the center of ...
The Influence of the Shear-Induced Pressure Gradient on Thunderstorm Motion
Publisher: American Meteorological Society
Abstract: In the present investigation we propose a simple theory to explain how a veering environmental wind shear vector can cause an initially symmetric updraft to grow preferentially to the right of the shear vector and acquire ...
Another Look at Downslope Winds. Part II: Nonlinear Amplification beneath Wave-Overturning Layers
Publisher: American Meteorological Society
Abstract: Numerical mountain wave simulations have documented that intense lee-slope winds frequently arise when wave-overturning occurs above the mountain. Explanations for this amplification process have been proposed by Clark and ...
Lifting by Convergence Lines
Publisher: American Meteorological Society
Abstract: The lifting depth of a convergence line in an unstratified boundary layer beneath a stably stratified atmosphere is examined with both analytical and numerical models. Cases are considered with and without flow in the layer ...
A Three-Dimensional Numerical Simulation of Splitting Severe Storms on 3 April 1964
Publisher: American Meteorological Society
Abstract: A three-dimensional numerical storm model is used to investigate the observed splitting of several reflectivity echoes on 3 April 1964 in Oklahoma. Representative soundings from this day exhibit a nearly one-directional ...
Adaptive Grid Refinement for Two-Dimensional and Three-Dimensional Nonhydrostatic Atmospheric Flow
Publisher: American Meteorological Society
Abstract: Although atmospheric phenomena tend to be localized in both time and space, numerical models generally employ only uniform discretizations or fixed nested grids. An adaptive grid technique implemented in 2D and 3D ...
The Stability of Time-Split Numerical Methods for the Hydrostatic and the Nonhydrostatic Elastic Equations
Publisher: American Meteorological Society
Abstract: The mathematical equivalence of the linearized two-dimensional (2D) shallow-water system and the 2D acoustic-advection system strongly suggests that time-split schemes designed for the hydrostatic equations can be employed ...