Automatic All Quadrilateral Mesh Adaption through Refinement and Coarsening

Anderson, Bret D.; Benzley, Steven E.; Owen, Steven J.

doi:10.1007/978-3-642-04319-2_32

Cited by 20 publications

(11 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Refined grids are generated through the use of CUBIT, a software package developed at Sandia National Laboratories (Anderson et al 2009). This software allows the user to create a globally uniform cubed-sphere grid of a specified resolution and then refine over userselected areas.…”

Section: Variable Resolution In Cam-sementioning

confidence: 99%

Using Variable-Resolution Meshes to Model Tropical Cyclones in the Community Atmosphere Model

Zarzycki

Jablonowski

Taylor

2014

Monthly Weather Review

View full text Add to dashboard Cite

A statically nested, variable-mesh option has recently been introduced into the Community Atmosphere Model's (CAM's) Spectral Element (SE) dynamical core that has become the default in CAM version 5.3. This paper presents a series of tests of increasing complexity that highlight the use of variable-resolution grids in CAM-SE to improve tropical cyclone representation by dynamically resolving storms without requiring the computational demand of a global high-resolution grid. As a simplified initial test, a dry vortex is advected through grid transition regions in variable-resolution meshes on an irrotational planet with the CAM subgrid parameterization package turned off. Vortex structure and intensity is only affected by grid resolution and no spurious artifacts are observed. CAM-SE model simulations using an idealized tropical cyclone test case on an aquaplanet show no numerical distortion or wave reflection when the cyclone interacts with an abrupt transition region. Using the same test case, the authors demonstrate that a regionally refined mesh with significantly fewer degrees of freedom can produce the same local results as a globally uniform grid. Additionally, the authors discuss a more complex aquaplanet experiment with meridionally varying sea surface temperatures that reproduces a quasi-realistic global climate. Tropical cyclogenesis is facilitated without the need for vortex bogusing in a high-resolution patch embedded within a global grid that is otherwise too coarse to resolve realistic tropical cyclones in CAM.

show abstract

Section: Variable Resolution In Cam-sementioning

confidence: 99%

Using Variable-Resolution Meshes to Model Tropical Cyclones in the Community Atmosphere Model

Zarzycki

Jablonowski

Taylor

2014

Monthly Weather Review

View full text Add to dashboard Cite

show abstract

“…Elements in the refinement region are divided into four and those bordering the region into three (Anderson et al 2009). The user selects a base resolution and subsequently refines over an arbitrary number of regions of arbitrary spatial extent.…”

Section: A Cam-sementioning

confidence: 99%

Aquaplanet Experiments Using CAM’s Variable-Resolution Dynamical Core

et al. 2014

View full text Add to dashboard Cite

A variable-resolution option has been added within the spectral element (SE) dynamical core of the U.S. Department of Energy (DOE)-NCAR Community Atmosphere Model (CAM). CAM-SE allows for static refinement via conforming quadrilateral meshes on the cubed sphere. This paper investigates the effect of mesh refinement in a climate model by running variable-resolution (var-res) simulations on an aquaplanet. The variable-resolution grid is a 28 (;222 km) grid with a refined patch of 0.258 (;28 km) resolution centered at the equator. Climatology statistics from these simulations are compared to globally uniform runs of 28 and 0.258. A significant resolution dependence exists when using the CAM version 4 (CAM4) subgrid physical parameterization package across scales. Global cloud fraction decreases and equatorial precipitation increases with finer horizontal resolution, resulting in drastically different climates between the uniform grid runs and a physics-induced grid imprinting in the var-res simulation. Using CAM version 5 (CAM5) physics significantly improves cloud scaling at different grid resolutions. Additional precipitation at the equator in the highresolution mesh results in collocated zonally anomalous divergence in both var-res simulations, although this feature is much weaker in CAM5 than CAM4. The equilibrium solution at each grid spacing within the var-res simulations captures the majority of the resolution signal of the corresponding globally uniform grids. The var-res simulation exhibits good performance with respect to wave propagation, including equatorial regions where waves pass through grid transitions. In addition, the increased frequency of high-precipitation events in the refined 0.258 area within the var-res simulations matches that observed in the global 0.258 simulations.

show abstract

“…For these applications, the dynamical cores ideally should satisfy several properties, such as conservation, compatible or mimetic properties, and accurate representation of global-to-mesoscale flows (Taylor and Fournier 2010;Ringler et al 2010;Skamarock 2011;Staniforth and Thuburn 2012). These numerical techniques, along with progress in grid generation (Tomita et al 2002;Anderson et al 2009;Ju et al 2011;Walko and Avissar 2011), make it possible to increase grid resolution locally while maintaining a quasi-uniform resolution outside the refined domain. The associated grids are often described as unstructured because each cell is identified by a unique index and its connectivity to the neighboring cells, due to nonrectangular cell shapes and/or local coordinate system used in the numerical scheme.…”

Section: B Emerging Challenges In Physics-dynamics Coupling With Mulmentioning

confidence: 99%

Physics–Dynamics Coupling in Weather, Climate, and Earth System Models: Challenges and Recent Progress

Groß

Wan

Rasch

et al. 2018

Monthly Weather Review

View full text Add to dashboard Cite

Numerical weather, climate, or Earth system models involve the coupling of components. At a broad level, these components can be classified as the resolved fluid dynamics, unresolved fluid dynamical aspects (i.e., those represented by physical parameterizations such as subgrid-scale mixing), and nonfluid dynamical aspects such as radiation and microphysical processes. Typically, each component is developed, at least initially, independently. Once development is mature, the components are coupled to deliver a model of the required complexity. The implementation of the coupling can have a significant impact on the model. As the error associated with each component decreases, the errors introduced by the coupling will eventually dominate. Hence, any improvement in one of the components is unlikely to improve the performance of the overall system. The challenges associated with combining the components to create a coherent model are here termed physics–dynamics coupling. The issue goes beyond the coupling between the parameterizations and the resolved fluid dynamics. This paper highlights recent progress and some of the current challenges. It focuses on three objectives: to illustrate the phenomenology of the coupling problem with references to examples in the literature, to show how the problem can be analyzed, and to create awareness of the issue across the disciplines and specializations. The topics addressed are different ways of advancing full models in time, approaches to understanding the role of the coupling and evaluation of approaches, coupling ocean and atmosphere models, thermodynamic compatibility between model components, and emerging issues such as those that arise as model resolutions increase and/or models use variable resolutions.

show abstract

Automatic All Quadrilateral Mesh Adaption through Refinement and Coarsening

Cited by 20 publications

References 17 publications

Using Variable-Resolution Meshes to Model Tropical Cyclones in the Community Atmosphere Model

Using Variable-Resolution Meshes to Model Tropical Cyclones in the Community Atmosphere Model

Aquaplanet Experiments Using CAM’s Variable-Resolution Dynamical Core

Physics–Dynamics Coupling in Weather, Climate, and Earth System Models: Challenges and Recent Progress

Contact Info

Product

Resources

About