A5086366156- Climate variability and models
- Oceanographic and Atmospheric Processes
- Meteorological Phenomena and Simulations
- Arctic and Antarctic ice dynamics
- Cryospheric studies and observations
- Methane Hydrates and Related Phenomena
- Tropical and Extratropical Cyclones Research
- Atmospheric and Environmental Gas Dynamics
- Geophysics and Gravity Measurements
- Fluid Dynamics and Turbulent Flows
- Ocean Waves and Remote Sensing
- Geology and Paleoclimatology Research
- Computational Fluid Dynamics and Aerodynamics
- Soil erosion and sediment transport
- Scientific Computing and Data Management
- Coastal and Marine Dynamics
- Reservoir Engineering and Simulation Methods
- Hydrology and Watershed Management Studies
- Plant Water Relations and Carbon Dynamics
- Hydrology and Sediment Transport Processes
- Advanced Numerical Methods in Computational Mathematics
- Tree-ring climate responses
- Simulation Techniques and Applications
- Aerodynamics and Acoustics in Jet Flows
- Solar and Space Plasma Dynamics
Los Alamos National Laboratory
2012-2022
Office of Science and Technology Policy
2021-2022
United States House of Representatives
2019-2022
University of Reading
2009
Imperial College London
2009
Met Office
2009
National Centre for Atmospheric Science
2009
Colorado State University
1999-2006
Cornell University
1992-1999
This work documents the first version of U.S. Department Energy (DOE) new Exascale Earth System Model (E3SMv1). We focus on standard resolution fully coupled physical model designed to address DOE mission-relevant water cycle questions. Its components include atmosphere and land (110-km grid spacing), ocean sea ice (60 km in midlatitudes 30 at equator poles), river transport (55 km) models. base configuration will also serve as a foundation for additional configurations exploring higher...
Abstract The formulation of a fully compressible nonhydrostatic atmospheric model called the Model for Prediction Across Scales–Atmosphere (MPAS-A) is described. solver discretized using centroidal Voronoi meshes and C-grid staggering prognostic variables, it incorporates split-explicit time-integration technique used in many existing meso- cloud-scale models. MPAS can be applied to globe, over limited areas on Cartesian planes. are unstructured grids that permit variable horizontal...
We revisit the challenges and prospects for ocean circulation models following Griffies et al. (2010). Over past decade, evolved through improved understanding, numerics, spatial discretization, grid configurations, parameterizations, data assimilation, environmental monitoring, process-level observations modeling. Important large scale applications over last decade are simulations of Southern Ocean, Meridional Overturning Circulation its variability, regional sea level change. Submesoscale...
Abstract The Energy Exascale Earth System Model (E3SM) is a new coupled system model sponsored by the U.S Department of Energy. Here we present E3SM global simulations using active ocean and sea ice that are driven Coordinated Ocean‐ice Reference Experiments II (CORE‐II) interannual atmospheric forcing data set. components MPAS‐Ocean MPAS‐Seaice, which use for Prediction Across Scales (MPAS) framework run on unstructured horizontal meshes. For this study, grid cells vary from 30 to 60 km...
Abstract The time scales of the Paris Climate Agreement indicate urgent action is required on climate policies over next few decades, in order to avoid worst risks posed by change. On these relatively short combined effect variability and change are both key drivers extreme events, with decadal also important for infrastructure planning. Hence, assess risk such scales, we require models be able represent aspects internally driven response changing forcings. In this paper argue that now have...
We evaluate the Community ocean Vertical Mixing (CVMix) project version of K-profile parameterization (KPP). For this purpose, one-dimensional KPP simulations are compared across a suite oceanographically relevant regimes against large eddy (LES). The LES is forced with horizontally uniform boundary fluxes and has initial conditions, allowing its horizontal average to be tests. find standard configuration consistent many forcing regimes, supporting physical basis KPP. Our evaluation...
The processes responsible for freshwater flux from the Antarctic Ice Sheet (AIS), ice-shelf basal melting and iceberg calving, are generally poorly represented in current Earth System Models (ESMs). Here we document cryosphere configuration of U.S. Department Energy's Energy Exascale Model (E3SM) v1.2. This includes simulating melting, which has been implemented through ocean circulation within static cavities, allowing ability to calculate melt rates associated heat fluxes. In addition,...
A new approach to climate simulation uses geodesic grids generated from an icosahedron and could become on attractive alternative current models. We implemented atmospheric general circulation model using a discretization of the sphere. Our message-passing interface runs efficiently massively parallel machines.
Abstract The ability to solve the global shallow-water equations with a conforming, variable-resolution mesh is evaluated using standard test cases. While long-term motivation for this study creation of climate modeling framework capable resolving different spatial and temporal scales in regions, process begins an analysis system order better understand strengths weaknesses approach developed herein. multiresolution meshes are spherical centroidal Voronoi tessellations where single,...
Abstract Results from aquaplanet experiments performed using the Model for Prediction across Scales (MPAS) hydrostatic dynamical core implemented within Department of Energy (DOE)–NCAR Community Atmosphere (CAM) are presented. MPAS is an unstructured-grid approach to climate system modeling that supports both quasi-uniform and variable-resolution meshing sphere based on conforming grids. Using simulations at resolutions 30, 60, 120, 240 km, authors evaluate performance CAM-MPAS via its...
Abstract Rapid and broad-scale forest mortality associated with recent droughts, rising temperature, insect outbreaks has been observed over western North America (NA). Climate models project additional future warming increasing drought water stress for this region. To assess potential changes in vegetation distributions NA, the Community Earth System Model (CESM) coupled its Dynamic Global Vegetation (DGVM) was used under A2 emissions scenario. better span uncertainties climate, eight sea...
Abstract This study presents a diagnosis of multiresolution approach using the Model for Prediction Across Scales–Atmosphere (MPAS-A) simulating regional climate. Four Atmospheric Intercomparison Project (AMIP) experiments were conducted 1999–2009. In first two experiments, MPAS-A was configured global quasi-uniform grids at 120- and 30-km grid spacing. other variable-resolution (VR) mesh with local refinement 30 km over North America South embedded in domain 120 elsewhere. Precipitation...
Abstract The Southern Ocean overturning circulation is driven by winds, heat fluxes, and freshwater sources. Among these sources of freshwater, Antarctic sea ice formation melting play the dominant role. Even though ice-shelf melt relatively small in magnitude, it located close to regions convection, where may influence dense water formation. Here, we explore impacts on water-mass transformation (WMT) using simulations from Energy Exascale Earth System Model (E3SM) both with without explicit...
This paper documents the development and testing of a new type atmospheric dynamical core. The model solves vorticity divergence equations in place momentum equation. is discretized horizontal using geodesic grid that nearly uniform over entire globe. formed by recursively bisecting triangular faces regular icosahedron projecting those vertices onto surface sphere. All analytic operators are reduced to line integrals, which numerically evaluated with second-order accuracy. In vertical...
Abstract The properties of C-grid staggered spatial discretizations the shallow-water equations on regular Delaunay triangulations sphere are analyzed. Mass-conserving schemes that also conserve either energy or potential enstrophy derived, and their features analogous to those quadrilateral grids. Results numerical tests carried out with explicit semi-implicit time show potential-enstrophy-conserving scheme is able reproduce correctly main large-scale atmospheric motion power spectra for...
The numerical modeling of glacier and ice sheet evolution is a subject growing interest, in part because the potential for models to inform estimates global sea level change. This paper focuses on development model that determines velocity pressure fields within an sheet. Our features high‐fidelity mathematical involving nonlinear Stokes system combinations no‐sliding sliding basal boundary conditions, high‐order accurate finite element discretizations based variable resolution grids, highly...
Abstract This study compares the error characteristics associated with two grid refinement approaches including global variable resolution and nesting for high-resolution regional climate modeling. The variable-resolution model, Model Prediction Across Scales-Atmosphere (MPAS-A), limited-area Weather Research Forecasting (WRF), are compared in an idealized aquaplanet context. For MPAS-A, simulations have been performed a quasi-uniform-resolution domain at coarse (1°) high (0.25°) resolution,...
Using the shallow water equations, a numerical framework on spherical geodesic grid that conserves domain-integrated mass, potential vorticity, enstrophy, and total energy is developed. The scheme equally applicable to hexagonal grids plane grids. This new compared its predecessor it shown does considerably better in conserving enstrophy energy. Furthermore, simulation of geostrophic turbulence, produces spectra with slopes approximately K−3 K−1, respectively, where K wavenumber. These are...
Global climate models (GCMs) are the primary tools for predicting evolution of system. Through decades development, GCMs have demonstrated useful skill in simulating at continental to global scales. However, large uncertainties remain projecting change regional scales, which limits ability scientists help decision makers cities and communities strategize how best adapt mitigate change.