Atmospheric Dynamics Modeling Group



Atmospheric Dynamics Modeling Group / Education

The Dynamical Core Model Intercomparison Project (DCMIP-2016) and Summer School:
Future-Generation Non-Hydrostatic Weather and Climate Models

DCMIP-2016 Summer School on Future-Generation Non-Hydrostatic Weather and Climate Models

Boulder, CO, June, 6 - June, 17 2016

Organized by Paul Ullrich (University of California, Davis), Christiane Jablonowski (University of Michigan), Kevin Reed (Stony Brook University), Colin Zarzycki (NCAR), James Kent (University of South Wales, U.K.), Peter H. Lauritzen (NCAR) and Ramachandran D. Nair (NCAR)

We have organized a summer school and model intercomparison workshop with special focus on the newest non-hydrostatic global models. We invited students, postdocs and the international dynamical core modeling community to join us at the National Center for Atmospheric Research (NCAR, Boulder, CO) for 2 weeks from June/6-17/2016 for an exciting student-focused and research-driven event that led to an unprecedented dynamical core intercomparison project. The new aspects were that DCMIP-2016 focused very strongly on idealized dynamical core test cases with simple moisture feedbacks to assess the physics-dynamics coupling and interactions. As DCMIP-2012, DCMIP-2016 has been endorsed by the WMO Working Group on Numerical Experimentation (WGNE). The summer school and model intercomparison workshop is supported by cyberinfrastucture tools like shared workspaces via the Earth System CoG environment.

We explore new test techniques for non-hydrostatic models that are also applicable at hydrostatic scales. Examples are a new moist baroclinic wave test case without topography (applicable to both shallow-atmosphere and deep-atmosphere dynamical core equation sets) and a tropical cyclone test case of intermediate complexity that not only assesses the dynamical core but also includes a 'simple physics' package with a Kessler-type warm-rain scheme. It lets us investigate non-linear interactions and the physics-dynamics coupling. The third test is a supercell system on a reduced-size Earth that gives insight into non-hydrostatic motions at low computational cost.

Figure: Participants of DCMIP-2016 at the NCAR Center Green Lab in June 2016 (photo: UCAR copyright)

The Dynamical Core Model Intercomparison Project (DCMIP-2012) and Summer School:
Future-Generation Non-Hydrostatic Weather and Climate Models

DCMIP-2012 Summer School on Future-Generation Non-Hydrostatic Weather and Climate Models

Boulder, CO, July, 30 - August, 10 2012

Organized by Christiane Jablonowski (University of Michigan), Paul Ullrich (University of California, Davis), James Kent (University of South Wales, U.K.), Kevin Reed (Stony Brook University), Peter H. Lauritzen (NCAR), Ramachandran D. Nair (NCAR) and Mark Taylor (Sandia National Laboratories)

In 2012, we organized a summer school and model intercomparison workshop with special focus on non-hydrostatic global models which are under development right now. We invited students and the international dynamical core modeling community to join us at the National Center for Atmospheric Resaearch (NCAR, Boulder, CO) for 2 weeks from July/30-August/10/2012 for an exciting student-focused and research-driven event that will led to an unprecedented dynamical core intercomparison project, even broader in scale than our 2008 workshop. The event has been endorsed by the WMO Working Group on Numerical Experimentation (WGNE). The summer school and model intercomparison workshop was supported by newly developed cyberinfrastucture tools like shared workspaces that we developed in collaboration with NOAA and NCAR under an NSF grant.

We explored new test techniques for non-hydrostatic models that are also applicable at hydrostatic scales. Examples are our newly developed tropical cyclone test case of intermediate complexity that not only assesses the dynamical core but also includes a 'simple physics' package. It lets us investigate non-linear interactions and the physics-dynamics coupling. Other test cases include 'small Earth' experiments that give insight into non-hydrostatic motions at low computational cost.

Figure: Participants of DCMIP-2012 at the NCAR Foothill Lab in August 2012

2008 NCAR Advanced Study Program (ASP) Summer Colloquium

Numerical Techniques for Global Atmospheric Models

Boulder, CO, June 1-13, 2008

Organized by Peter H. Lauritzen (NCAR), Christiane Jablonowski (University of Michigan), Mark Taylor (Sandia National Laboratories) and Ramachandran D. Nair (NCAR)

The 2-week summer colloquium titled "Numerical Techniques for Global Atmospheric Models" surveyed the latest developments in numerical methods for the dynamical cores of Atmospheric General Circulation Models. The objectives of the colloquium were (1) to teach a large group of about 40 graduate students in atmospheric science and mathematics how today's and future dynamical cores are or need to be built, (2) to invite over 10 dynamical core modeling groups to NCAR for an unprecedented student-run dynamical core intercomparison project, (3) to establish new dynamical core test cases in the community and (4) to invite keynote speakers to NCAR that give lectures on modern numerical techniques and innovative computational meshes. More information can also be found on NCAR's CISL webpage.

Photo: Participants of the NCAR ASP 2008 Colloquium on Numerical Techniques for Global Atmospheric Models.

Photo: Organizers of the NCAR ASP 2008 Colloquium on Numerical Techniques for Global Atmospheric Models. Left to right: Ram Nair, Peter Lauritzen, Mark Taylor, Christiane Jablonowski


IPAM Long Program: Model and Data Hierarchies for Simulating and Understanding Climate

The Institute for Pure and Applied Mathematics (IPAM) is an NSF Math Institute on the campus of UCLA in Los Angeles, CA. In the spring of 2010 (March 8 - June 11, 2010) IPAM held a 13-week long program on Model and Data Hierarchies for Simulating and Understanding Climate. There were four one-week workshops and a week-long tutorial-workshop (first week) embedded into the long program. The themes of the four workshops addressed (1) the equation sets for climate modeling, (2) the numerical methods and hierarchies, (3) the subgrid-scale physics parameterizations and (4) data analysis and assimilation aspects. We were involved in several of the IPAM events. Prof. Jablonowski was a speaker at the tutorial-workshop, and an organizer (& speaker) of Workshop II: Numerical Hierarchies for Climate Modeling.

Figure: Adaptive Mesh Simulation with a Finite Volume shallow water model (St-Cyr, Jablonowski et al., MWR 2008). The figure shows the relative vorticity field at day 6 of a barotropically unstable wave. Nonuniform resolutions and other topics were discussed at the IPAM Workshop II in April 2010.


Tutorials on 'Parallel Computing 101' at the conference SuperComputing

For over 16 years Prof. Jablonowski has been collaborating with Prof. Quentin Stout (Computer Science and Engineering, University of Michigan) on the Parallel Computing tutorial 'Parallel Computing 101' which we update substantially every year. This tutorial provides a comprehensive overview of parallel computing, emphasizing those aspects most relevant to the user. It discusses software and hardware, with an emphasis on standards, portability, and systems that are widely available.

The tutorial surveys basic parallel computing concepts, using examples selected from large-scale engineering and scientific problems. These examples illustrate using MPI on distributed memory systems, OpenMP on shared memory systems, and MPI+OpenMP on hybrid systems. It discusses numerous parallelization approaches, and software engineering and performance improvement aspects, including the use of state-of-the-art tools. The tutorial helps attendees make intelligent decisions by covering the primary options that are available, explaining how they are used and what they are most suitable for. Extensive pointers to the literature and web-based resources are provided to facilitate follow-up studies. In recent years, the number of participants has exceeded 100. Among the participants are managers, students, commercial employees, researchers and software engineers from national research centers. Most recently, we taught it at SuperComputing '16 in Salt Lake City, UT, in November 2016 and at MASA Langley (May 2017). We will teach the tutorial again on Nov/12/2017 at SuperComputing '17 in Denver, CO.

Photo: Christiane Jablonowski and Quentin Stout at SuperComputing '07 in Reno, NV. The photo was taken by Ed Burnette who wrote about the Parallel Computing tutorial in his blog.


 

    Video Promotion for 'Parallel Computing 101': Full-day tutorial at the SuperComputing Conference Series

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Undergraduate course at the University of Michigan: Earth System Dynamics (CLIMATE 321)

The sophomore course Earth System Dynamics gives an introduction to the dynamics of the atmosphere, oceans and the solid earth. The course introduces the equations of motion that govern the motions of the Earth's Systems. We derive the full equation set and then discuss various approximations to study the components of the Earth's system. The first half of the course addresses the dynamics of the atmosphere and climate system. Special attention is paid to the dominant balances in the atmosphere, like the geostrophic balance or hydrostatic balance. The second half of the course focuses on ocean, cryosphere and solid Earth dynamics, and is taught by a faculty member from the UM Department of Geological Sciences. The course is quantitative and based on physical and mathematical principles.

Figure: Satellite image of the NASA Terra satellite, The image shows two spiraling storms, formed simultaneously above Iceland and Scotland on Jan/2/1007. The air in the low pressure systems rotates counterclockwise as expected in the Northern Hemisphere.

The lecture notes (PowerPoint files) for the first half of the course can be downloaded here. These are the lecture notes from the Winter 2009 term:

1 Introduction to the course

2 Characteristics of the atmosphere

3 Ideal gas law, hydrostatic equation, hypsometric equation, mathematical tools

4 Vorticity, divergence, spherical coordinates

5 Material derivative, advection, pressure gradient force (surface force)

6 & 7 Viscous force, gravitational force, introduction to apparent forces

8 Centrifugal force, gravity, Coriolis force

9 Momentum equations, scale analysis, geostrophic balance, hydrostatic balance

10 Continuity equation, thermodynamic equation, total energy equation

11 Potential temperature (Poisson equation), dry adiabatic lapse rate, static stability, Brunt-Vaisala frequency

12 Vertical pressure coordinate, thermal wind relationship

13 Equations of motion in pressure coordinates, pressure tendency equation, evolution of an idealized low


Graduate course at the University of Michigan: Atmospheric Dynamics (CLIMATE 451)

This graduate-level course provides an in-depth discussion of atmospheric motions. We start with a review of the equations of motion and dominant balances, and briefly remind ourselves of the quasi-geostrophic theory. This is our background knowledge. We then discuss waves and instabilities in the atmosphere. This includes the derivation of dispersion relations and a discussion of barotropic, baroclinic, inertial, Kelvin-Helmholtz and static instabilities. The course reviews the general circulation of the atmosphere including the Hadley cells, planetary and equatorial waves and gives an overview of the dynamics of the middle atmosphere. We address the wave-mean flow interaction, wavenumber-frequency diagrams, the mean and transformed Eulerian mean circulation, tropical meteorology, energy and angular momentum budgets, and atmospheric modeling.

Figure: Wheeler-Kiladis wavenumber-frequency diagrams based on ECMWF's ERA40 reanalysis data set. Left: wavenumber-frequency spectrum for temperature during Jan-Jun 1980 at 50mb altitude, averaged between 10S-10N. Kelvin wave stands out, with wavenumber of about 1 and period of 15-20 days. Right: wavenumber-frequency diagram for temperature during Jun-Nov 1980 at 30mb altitude, averaged between 10S-10N. A Rossby-Gravity wave signal can be picked out at about wavenumber 4-5, with a frequency of about 3-5 days.


Graduate Course at the University of Michigan: The Art of Climate Modeling (CLIMATE 589)

The course discusses how atmospheric general circulation models (GCMs) are or need to be built, thereby exposing the many design choices atmospheric modelers face. The course addresses both the dynamical cores of GCMs and selected physical parameterizations. It is a hands-on class with journal article reviews and many modeling projects that lets us explore NCAR's newest Community Earth System Model CESM. We utilize modern software and hardware technologies, shared Wiki-based workspaces, learn about numerical methods, model uncertainties and the coupling of model components, develop computing skills and deal with data.

 

Figure: Left: Example of an idealized simulation with the NCAR Finite-Volume (FV) dynamical core. The figure shows the 850 hPa temperature field of an idealized baroclinic wave as documented by Jablonowski and Williamson (QJ, 2006) and in the Jablonowski and Williamson NCAR Technical Report TN-469+STR (2006). Right: Example of a model grid (figure taken from David Noone's web page at the University of Colorado, Boulder).

Figure: Cubed-sphere and hexagonal computational grids on the sphere which are discussed in the course.


Latest update: August 16th, 2017