First Field Tests of ESMF

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First Field Tests of ESMF
NCAR/LANL CCSM
Climate
GFDL FMS Suite
Data Assimilation
NASA GMAO Analysis
GMAO Seasonal Forecast
MITgcm
Weather
Chris Hill ESMF Community Meeting 2004 Boulder, CO

NCEP Forecast
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Outline

• Interoperability Experiments
• CAM SSI
• CAM MITgcm
• MITgcm GFDL Atmos/Land/Sea-ice
• Conclusions

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Interoperability

• We want to validate and demonstrate
• ESMF is compatible with existing applications.
• ESMF can provide the technology to wire together
  these applications to form the basis for new
  configurations.

Interoperability
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ESMF Interoperability Demonstrations
Due by completion of project - three highlighted
have been demonstrated.
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Specific Applications in first three
demonstrations
Sources are available over the web through ESMF
site (ESMF 1.5 and 1.6 based).

• Each demonstrates how ESMF solves the technical
  aspects of software interoperability, not the
  science of building and coupling systems

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Outline

• Interoperability Experiments
• CAM SSI
• CAM MITgcm
• MITgcm GFDL Atmos/Land/Sea-ice
• Conclusions

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CAM-SSI Interoperability

• NCAR Finite-volume Community Atmospheric Model
  (fvCAM)
• Finite-volume Dynamical Core developed at
  NASA/GSFC by S.-J. Lin
• Latest NCAR Physics packages
• NCEP Spectral Statistical Interpolation (SSI)
  System
• Assimilates a wealth of conventional and
  satellite data
• Demo utilizes same observational stream used
  operationally at NCEP
• For this Demo, we have developed both fvCAM and
  SSI as ESMF Grid Components and coupled them
  using ESMF services.
• This is the first time a state-of-the-art data
  assimilation system has been coupled to the CAM

NCEP SSI
NCAR fvCAM
ESMF COUPLER COMPONENT
SSI ENCAPSULATED AS ESMF GRIDDED COMPONENT
NCAR fvCAM ENCAPSULATED AS ESMF GRIDDED COMPONENT
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CAM-SSI Interoperability Demonstration

• Can be downloaded to see how components were
  encapsulated
• Can be run on NCAR IBMs blackforest and
  bluesky
• when run the experiment executes as follows

5 ESMF based interoperability is demonstrated!
4 SSI returns updates to coupler which puts
them in form for CAM.
2 CAM Atmospheric temperatures are placed in an
ESMF Export State and passed to a coupler that
can map CAM fields to SSI fields.
1 CAM computes Atmospheric temperatures
3 Coupler passes SSI its input fields and SSI
computes analysis increments (using production
observation stream).
NCEP SSI
NCAR fvCAM
ESMF COUPLER COMPONENT
SSI ENCAPSULATED AS ESMF GRIDDED COMPONENT
NCAR fvCAM ENCAPSULATED AS ESMF GRIDDED COMPONENT
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Outline

• Interoperability Experiments
• CAM SSI
• CAM MITgcm
• MITgcm GFDL Atmos/Land/Sea-ice
• Conclusions

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MITgcm CAM Interoperability
In this experiment CAM is configured with 2
degree latitudinal resolution and 2.5 degree
longitudinal resolution, computational grid is
144x90 grid points in the horizontal. The MITgcm
ocean configuration uses 2.8125 degree resolution
both zonally and meridionally. Both
configurations execute domain decomposed into
sixteen latitude circles, but at different
resolutions. The experiment runs on 16 cpus and
an ESMF coupler component using parallel
ESMF_Regrid is used to map between
them. Demonstration is done passing SST from
ocean to atmosphere images show output from
actual runs.
MITgcm
NCAR fvCAM
ESMF COUPLER COMPONENT
MITgcm ENCAPSULATED AS ESMF GRIDDED COMPONENT
NCAR fvCAM ENCAPSULATED AS ESMF GRIDDED COMPONENT
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Outline

• Interoperability Experiments
• CAM SSI
• CAM MITgcm
• MITgcm GFDL Atmos/Land/Sea-ice
• Conclusions

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GFDL Atm MITgcm Interoperability
In this experiment the atmosphere-land-ice
composite component is configured with 2 degree
latitudinal resolution and 2.5 degree
longitudinal resolution, computational grid is
144x90 grid points in the horizontal. The MITgcm
ocean configuration uses 2.8125 degree resolution
both zonally and meridionally. The MITgcm
configurations executes domain decomposed into
thirty latitude circles. The atmosphere component
executes decomposed into thirty longitude bands.
Demonstration is done passing SST from ocean to
atmosphere on 30 CPUs. In this experiment the
parallel regrid must map from latitude circle
decomposition to longitude band decomposition
images are from actual runs.
MITgcm Ocean
GFDL atmosphere-land-seaice (ALS) composite
ESMF COUPLER COMPONENT
MITgcm ENCAPSULATED AS ESMF GRIDDED COMPONENT
GFDL ALS
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Under the hood
Before
Existing code
After
ESMFrun()
ESMFinit()
ESMFfinal()
Component interface layer
myrun()
myinit()
myfinal()
Computational layer
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Outline

• Interoperability Experiments
• CAM SSI
• CAM MITgcm
• MITgcm GFDL Atmos/Land/Sea-ice
• Conclusions

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Summary
3 NCAR Community Atmospheric Model (CAM) coupled
to MITgcm ocean Atmosphere, ocean, and coupler
are set up as ESMF components Uses ESMF
regridding tools to pass SST between component.
2
1 GFDL B-grid atmosphere coupled to MITgcm
ocean Atmosphere, ocean, and coupler are set up
as ESMF components Uses ESMF regridding tools to
pass SST betweeen components.
Temperature SSI import Temperature SSI
export Analysis increments
NCAR Community Atmospheric Model (CAM) coupled to
NCEP Spectral Statistical Interpolation (SSI)
System, both set up as ESMF components.
Experiment utilizes same observational stream
used operationally at NCEP

• The same MITgcm are used in 1 and 3. The same CAM
  is used in 2 and 3. All that has to be changed is
  the ESMF couplers.
• Demonstrates how ESMF solves the technical
  aspects of software interoperability, not the
  science of building and coupling systems

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More Information

• ESMF website http//www.esmf.ucar.edu

Acknowledgements The ESMF is sponsored by the
NASA Goddard Earth Science Technology Office.