NSF NCAR | NASA GSFC | DOE LANL ANL | NOAA NCEP GFDL | MIT | U MICH
www.esmf.ucar.edu
Emergence of the Earth System Modeling Framework
NSIPP Seasonal Forecast
NCAR/LANL CCSM
NCEP Forecast
GFDL FMS Suite
MITgcm
NASA GMAO Analysis
ClimateData Assimilation
Weather
Cecelia DeLucaSymposium on the 50th Anniversary of ONWP
NSF NCAR | NASA GSFC | DOE LANL ANL | NOAA NCEP GFDL | MIT | U MICH
www.esmf.ucar.edu
MotivationIn NWP, seasonal prediction and climate research...
increased emphasis on detailed representation of individual physical processes; requires many teams of specialists to contribute components to an overall modeling system
In computing technology... increase in hardware and software complexity in high-performance computing, shift toward the use of scalable computing architectures
In software …development of frameworks (integrated libraries), such as the GFDL Flexible Modeling System (FMS) and Goddard Earth Modeling System (GEMS) that encourage software reuse and interoperability
The ESMF is a community effort to tame the complexity of models and the computing environment. It leverages, unifies and extends existing software frameworks, breaking down institutional barriers and creating new opportunities for scientific contribution and collaboration.
NSF NCAR | NASA GSFC | DOE LANL ANL | NOAA NCEP GFDL | MIT | U MICH
www.esmf.ucar.edu
ESMF Project DescriptionGOALS: To increase software reuse, interoperability, ease of use and performance portability in
climate, weather, and data assimilation applications
PRODUCTS: • Core framework: Software for coupling geophysical components and utilities for building
components • Applications: Deployment of the ESMF in 15 of the nation’s leading climate and weather models,
assembly of 8 new science-motivated applications
METRICS:
RESOURCES and TIMELINE: $9.8M from NASA ESTO over 3 years, starting February 2002Ongoing support from the National Science Foundation
Reuse Interoperability Ease of Adoption Performance
15 applications use ESMF component coupling services and 3+ utilities
8 new applications comprised of never-before coupled components
2 codes adopt ESMF with < 2% lines of code changed, or within 120 FTE-hours
No more than 10% overhead in time to solution, no degradation in scaling
NSF NCAR | NASA GSFC | DOE LANL ANL | NOAA NCEP GFDL | MIT | U MICH
www.esmf.ucar.edu
ESMF Architecture
1. ESMF provides an environment for assembling geophysical components into applications, with support for ensembles and hierarchies.
2. ESMF provides a toolkit that components use to
i. increase interoperability
ii. improve performance portability
iii. abstract common services
ESMF InfrastructureData Classes: Bundle, Field, Grid, Array
Utility Classes: Clock, LogErr, DELayout, Machine
ESMF SuperstructureAppDriver
Component Classes: GridComp, CplComp, State
User Code
NSF NCAR | NASA GSFC | DOE LANL ANL | NOAA NCEP GFDL | MIT | U MICH
www.esmf.ucar.edu
Hierarchies and Ensembles
assim
sea iceocean
landatm
physics dycore
assim_atm
atmland
Seasonal Forecast
coupler
ESMF encourages applications to be assembled hierarchically and intuitively
Coupling interfaces are standard at each layer
Components can be used in different contexts
assim_atm
Ensemble Forecast
assim_atm assim_atm
ESMF supports ensembles with multiple instances of components running sequentially (and soon, concurrently)
NSF NCAR | NASA GSFC | DOE LANL ANL | NOAA NCEP GFDL | MIT | U MICH
www.esmf.ucar.edu
ESMF In More Detail…
• Fortran interfaces (mixed-language implementation)• Multi-platform support (SGI, Compaq, IBM, Linux - Intel, PGI, NAG, Absoft)• Clear, simple hierarchy of data objects (arrays, fields, bundles of fields,
components) for developing modeling codes• Toolkits for communications (redist, halo, etc.), time management, error
handling and logging, resource files, IO • Regridding library is on-line, parallelized version of SCRIP from LANL• Tools for multithreading, cache blocking, and load balancing integrated into
the architecture – development has been highly performance-aware!• Data objects and toolkits have consistent naming and behavior across the
framework
NSF NCAR | NASA GSFC | DOE LANL ANL | NOAA NCEP GFDL | MIT | U MICH
www.esmf.ucar.edu
The Benefits
• Standard interfaces to modeling components promote increased interoperability between centers, faster movement of modeling components from research to operations
• The ability to construct models hierarchically enables developers to add new modeling components more systematically and easily, facilitates development of complex coupled systems
• Multi-use objects mean that the same data structure can carry information about decomposition, communications, IO, coupling – this makes code smaller and simpler, and therefore less bug-prone and easier to maintain
• Shared utilities encourage efficient code development, higher quality tools, more robust codes
NSF NCAR | NASA GSFC | DOE LANL ANL | NOAA NCEP GFDL | MIT | U MICH
www.esmf.ucar.edu
Open Development• Open source• Currently ~800 unit tests, ~15 system tests are bundled with the ESMF
distribution, can be run in non-exhaustive or exhaustive modes• Results of nightly tests on many platforms are accessible on a Test and
Validation webpage• Test coverage, lines of code, requirements status are available on a Metrics
webpage• Exhaustive Reference Manual, including design and implementation notes, is
available on a Downloads and Documentation webpage
• Development is designed to allow users clear visibility into the workings and status of the system, to allow users to perform their own diagnostics, and to encourage community ownership
NSF NCAR | NASA GSFC | DOE LANL ANL | NOAA NCEP GFDL | MIT | U MICH
www.esmf.ucar.edu
ESMF Key Accomplishments• Public delivery of prototype ESMF v1.0 in May 2003• Monthly ESMF internal releases with steadily increasing functionality • Completion of first 3 coupling demonstrations using ESMF in March
2004– NCAR CAM with NCEP SSI– NCAR CAM with MITgcm ocean– GFDL B-grid atmosphere with MITgcm ocean– All codes above running as ESMF components and coupled using
the framework, codes available from Applications link on website– Other codes running as ESMF components: MOM4, GEOS-5– Less than 2% lines of source code change
• On track for delivery of ESMF v2.0 on 23 June 2004• 3rd Community Meeting to be held on 15 July 2004 at NCAR
NSF NCAR | NASA GSFC | DOE LANL ANL | NOAA NCEP GFDL | MIT | U MICH
www.esmf.ucar.edu
Interoperability Experiments Completed
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
3
NCAR Community Atmospheric Model (CAM) coupled to MITgcm ocean
Atmosphere, ocean, and coupler are set up as ESMF components
Uses ESMF regridding tools
1
GFDL B-grid atmosphere coupled to MITgcm ocean
Atmosphere, ocean, and coupler are set up as ESMF components
Uses ESMF regridding tools
2Temperature SSI import
Temperature SSI export
Temperature difference
NSF NCAR | NASA GSFC | DOE LANL ANL | NOAA NCEP GFDL | MIT | U MICH
www.esmf.ucar.edu
Next Steps– Integration with data archives and metadata standardization efforts,
anticipate collaboration with Earth System Grid (ESG) and European infrastructure project PRISM
– Integration with scientific model intercomparison projects (MIPs), anticipate collaboration with the Program for Climate Model Diagnosis and Intercomparison (PCMDI), other community efforts
– Integration with visualization and diagnostic tools for end-to-end modeling support, anticipate collaboration with the Earth Science Portal (ESP)
– ESMF “vision” for the future articulated in multi-agency white paper on the Publications and Talks webpage
NSF NCAR | NASA GSFC | DOE LANL ANL | NOAA NCEP GFDL | MIT | U MICH
www.esmf.ucar.edu
More Information
ESMF website: http://www.esmf.ucar.edu
3rd Community Meeting on 15 July at NCAR