A5079274357- Meteorological Phenomena and Simulations
- Climate variability and models
- Tropical and Extratropical Cyclones Research
- Computational Fluid Dynamics and Aerodynamics
- Atmospheric and Environmental Gas Dynamics
- Ionosphere and magnetosphere dynamics
- Atmospheric Ozone and Climate
- Fluid Dynamics and Turbulent Flows
- Ocean Waves and Remote Sensing
- Geophysics and Gravity Measurements
- Advanced Numerical Methods in Computational Mathematics
- Precipitation Measurement and Analysis
- Wind and Air Flow Studies
- Oceanographic and Atmospheric Processes
- Methane Hydrates and Related Phenomena
- Arctic and Antarctic ice dynamics
- Fluid Dynamics Simulations and Interactions
- Atmospheric chemistry and aerosols
- Fluid Dynamics and Vibration Analysis
- Solar and Space Plasma Dynamics
- Climate change and permafrost
- Distributed and Parallel Computing Systems
- Geological and Geophysical Studies
- Cryospheric studies and observations
- Earthquake Detection and Analysis
University of Michigan
2014-2024
Sandia National Laboratories
2023-2024
Michigan United
2022-2023
NOAA Great Lakes Environmental Research Laboratory
2022
NSF National Center for Atmospheric Research
2005-2008
University Corporation for Atmospheric Research
2004
Abstract We present an analysis of version 5.1 the Community Atmospheric Model (CAM5.1) at a high horizontal resolution. Intercomparison this global model approximately 0.25°, 1°, and 2° is presented for extreme daily precipitation as well suite seasonal mean fields. In general, amounts are larger in resolution than lower‐resolution configurations. many but not all locations and/or seasons, rates high‐resolution configuration higher more realistic. The produces tropical cyclones up to...
Abstract While a quantitative climate theory of tropical cyclone formation remains elusive, considerable progress has been made recently in our ability to simulate climatologies and understand the relationship between formation. Climate models are now able realistic rate global formation, although simulation Atlantic climatology challenging unless horizontal resolutions finer than 50 km employed. This article summarizes published research from idealized experiments Hurricane Working Group...
Abstract A deterministic initial‐value test case for dry dynamical cores of atmospheric general‐circulation models is presented that assesses the evolution an idealized baroclinic wave in northern hemisphere. The initial zonal state quasi‐realistic and completely defined by analytic expressions which are a steady‐state solution adiabatic inviscid primitive equations with pressure‐based vertical coordinates. two‐component strategy first evaluates ability discrete approximations to maintain...
Abstract Using a variable‐resolution option within the National Center for Atmospheric Research/Department of Energy Community Atmosphere Model (CAM) Spectral Element (SE) global model, refined nest at 0.25° (∼28 km) horizontal resolution located over North Atlantic is embedded 1° (∼111 grid. The grid designed such that fine cells are where tropical cyclones (TCs) observed to occur during TC season (June–November). Two simulations compared, one with refinement and control case no (globally...
Abstract A variable-resolution option has been added within the spectral element (SE) dynamical core of U.S. Department Energy (DOE)–NCAR Community Atmosphere Model (CAM). CAM-SE allows for static refinement via conforming quadrilateral meshes on cubed sphere. This paper investigates effect mesh in a climate model by running (var-res) simulations an aquaplanet. The grid is 2° (~222 km) with refined patch 0.25° (~28 resolution centered at equator. Climatology statistics from these are...
The paper introduces a moist, deterministic test case of intermediate complexity for Atmospheric General Circulation Models (AGCMs). We suggest pairing an AGCM dynamical core with simple physical parameterizations to the evolution single, idealized, initially weak vortex into tropical cyclone. initial conditions are based on seed that is in gradient‐wind and hydrostatic balance. suggested “simple‐physics” package consists bulk aerodynamic surface fluxes moisture, sensible heat momentum,...
In an effort to study the applicability of adaptive mesh refinement (AMR) techniques atmospheric models interpolation-based spectral element shallow water model on a cubed-sphere grid is compared block-structured finite volume method in latitude-longitude geometry. Both utilize non-conforming adaptation approach which doubles resolution at fine-coarse interfaces. The underlying AMR libraries are quad-tree based and ensure that neighboring regions can only differ by one level. via selected...
Abstract A statically nested, variable-mesh option has recently been introduced into the Community Atmosphere Model’s (CAM's) Spectral Element (SE) dynamical core that become default in CAM version 5.3. This paper presents a series of tests increasing complexity highlight use variable-resolution grids CAM-SE to improve tropical cyclone representation by dynamically resolving storms without requiring computational demand global high-resolution grid. As simplified initial test, dry vortex is...
Abstract Idealised studies of key dynamical features the atmosphere provide insight into behaviour atmospheric models. A very important, well understood, aspect midlatitude dynamics is baroclinic instability. This can be idealised by perturbing a vertically sheared basic state in geostrophic and hydrostatic balance. An unstable wave mode then results with exponential growth (due to linear dynamics) time until, eventually, nonlinear effects dominate breaks. new, unified, instability test case...
Abstract Tropical cyclone (TC) forecasts at 14-km horizontal resolution (0.125°) are completed using variable-resolution (V-R) grids within the Community Atmosphere Model (CAM). Forecasts integrated twice daily from 1 August to 31 October for both 2012 and 2013, with a high-resolution nest centered over North Atlantic eastern Pacific Ocean basins. Using CAM version 5 (CAM5) physical parameterization package, regional refinement is shown significantly increase TC track forecast skill relative...
Abstract Numerical weather, climate, or Earth system models involve the coupling of components. At a broad level, these components can be classified as resolved fluid dynamics, unresolved dynamical aspects (i.e., those represented by physical parameterizations such subgrid-scale mixing), and nonfluid radiation microphysical processes. Typically, each component is developed, at least initially, independently. Once development mature, are coupled to deliver model required complexity. The...
Abstract. This paper provides an overview of the United States (US) Department Energy's (DOE's) Energy Exascale Earth System Model version 2 (E3SMv2) fully coupled regionally refined model (RRM) and documents overall atmosphere, land, river results from Coupled Intercomparison Project 6 (CMIP6) DECK (Diagnosis, Evaluation, Characterization Klima) historical simulations – a first-of-its-kind set climate production using RRM. The North American (NA) RRM (NARRM) is developed as high-resolution...
Abstract A new two-dimensional advection test on the surface of sphere is proposed. The combines a solid-body rotation and deformational flow field to form moving vortices over sphere. resulting time-dependent deforming vortex centers are located diametrically opposite sides move along predetermined great circle trajectory. horizontal wind nondivergent, analytic solution known at any time. During one revolution around initially smooth transported scalar develops strong gradients. Such an...
This paper presents a new approach for discretizing the nonhydrostatic Euler equations in Cartesian geometry using an operator-split time-stepping strategy and unstaggered upwind finite-volume model formulation. Following method of lines, spatial discretization governing leads to set coupled nonlinear ordinary differential equations. In general, explicit methods cannot be applied directly these because large aspect ratio between horizontal vertical grid spacing stringent restriction on time...
The Jablonowski test case is widely used for debugging and evaluating the numerical characteristics of global dynamical cores that describe fluid dynamics component Atmospheric General Circulation Models. defined in terms a steady‐state solution to equations motion an overlaid perturbation triggers baroclinically unstable wave. initial conditions are zonally symmetric. Therefore, design has potential favor models built upon regular latitude‐longitude or Gaussian grids. Here we suggest...
Abstract Using the spectral element (SE) dynamical core within National Center for Atmospheric Research–Department of Energy Community Atmosphere Model (CAM), a regionally refined nest at 0.25° (~28 km) horizontal resolution located over North Atlantic is embedded global 1° (~111 grid. A 23-yr simulation using Intercomparison Project (AMIP) protocols and default CAM, version 5, physics compared to an identically forced run grid without refinement. The addition patch basin does not noticeably...
Abstract. Recently, a standard test case suite for 2-D linear transport on the sphere was proposed to assess important aspects of accuracy in geophysical fluid dynamics with "minimal" set idealized model configurations/runs/diagnostics. Here we present results from 19 state-of-the-art scheme formulations based finite-difference/finite-volume methods as well emerging (in context atmospheric/oceanographic sciences) Galerkin methods. Discretization grids range traditional regular...
Abstract This paper describes an objective technique for detecting the extratropical transition (ET) of tropical cyclones (TCs) in high‐resolution gridded climate data. The algorithm is based on previous observational studies using phase spaces to define symmetry and vertical thermal structure cyclones. Storm tracking automated, allowing direct analysis Tracker performance North Atlantic assessed 23 years data from variable‐resolution Community Atmosphere Model (CAM) at two different...
Abstract A spherical 2D adaptive mesh refinement (AMR) technique is applied to the so-called Lin–Rood advection algorithm, which built upon a conservative and oscillation-free finite-volume discretization in flux form. The AMR design based on two modules: block-structured data layout grid library for parallel computer architectures. latter defines manages blocks geometry, provides user interfaces interpolation routines, supports communication load-balancing aspects applications. simulations...
This paper explores the impact of physical parameterization suite on evolution an idealized tropical cyclone within National Center for Atmospheric Research's (NCAR) Community Atmosphere Model (CAM). The CAM versions 3.1 and 4 are used to study development initially weak vortex in environment over a 10-day simulation period aqua-planet setup. main distinction between lies deep convection. now includes dilute plume Convective Available Potential Energy (CAPE) calculation Momentum Transport...
Abstract This paper evaluates the numerical convergence of very short (1 h) simulations carried out with a spectral‐element (SE) configuration Community Atmosphere Model version 5 (CAM5). While horizontal grid spacing is fixed at approximately 110 km, process‐coupling time step varied between 1800 and 1 s to reveal rate respect temporal resolution. Special attention paid behavior parameterized subgrid‐scale physics. First, dynamical core test reduced dynamics steps presented. The results...