Introduction to the Earth System Modeling Framework

1
Introduction to the Earth System Modeling
Framework

• International Workshop on Next Generation Climate
  Models for
• Advanced High Performance Computing Facilities
• March 12, 2002
• Cecelia DeLuca / Scientific Computing Division /
  NCAR
• Chris Hill / Massachusetts Institute of
  Technology
• V. Balaji / SGI NOAA Geophysical Fluid Dynamics
  Laboratory

2
Outline

• Background and Motivation
• ESMF Design Overview
• ESMF Codes
• Milestones
• Development Plan
• Beyond 2004 ESMF Evolution
• Additional Information and Events

3
Trends in Earth System Modeling

• In climate research and numerical weather
  prediction
• Increased emphasis on detailed representation of
  individual physical processes
• Requires many teams of specialists to contribute
  components to a coupled system
• In computing technology
• Increase in complexity and variety in
  high-performance computing hardware
• Community Response
• Abstraction of underlying hardware to provide
  uniform programming model across architectures
• Modular design for interchangeable dynamical
  cores and larger components
• Development of prototype frameworks - GFDL (FMS),
  NASA/GSFC (GEMS), others
• The Earth System Modeling Framework (ESMF) aims
  to unify and extend these efforts

4
Project Background
NASAs Earth Science Technology Office (ESTO)
proposed the creation of the ESMF in a September
2000 Cooperative Agreement Notice Large
collaboration developed three linked proposals
in responsePart I Core ESMF Development (PI
Killeen, NCAR)Part II Modeling Applications
(PI Marshall, MIT)Part III Data Assimilation
Applications (PI da Silva, NASA DAO)
5
Project Organization
NASA ESTO
Part I
Part II
Part III
Data Assimilation Deployment
Core Framework Development
Prognostic Model Deployment
NSF NCAR PI
MIT PI
NASA DAO PI
Part I Proposal Specific Milestones
Part II Proposal Specific Milestones
Part III Proposal Specific Milestones
Joint Milestones
Joint Milestones
Joint Milestones
Joint Specification Team Requirements
Analysis System Architecture API Specification
6
Objectives of the ESMF

• Facilitate the exchange of scientific codes
  (interoperability)
• Promote the reuse of standardized technical
  software while preserving computational
  efficiency
• Focus community resources to preserve performance
  portability in a volatile computing environment
• Share overhead costs of the housekeeping aspects
  of software development
• Provide greater institutional continuity to model
  development efforts

7
Framework Architecture
8
Application Architecture
Coupling Layer
ESMF Superstructure
Model Layer
User Code
Fields and Grids Layer
ESMF Infrastructure
Low Level Utilities
External Libraries
BLAS, MPI, NetCDF,
9
ESMF CodesModeling Applications
10
ESMF CodesData Assimilation Applications
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Final Milestones

• Tested, optimized core framework software and
  documentation
• Support for many platforms, including commodity
  clusters
• All ESMF codes will achieve full ESMF compliance
• Will use coupling superstructure and utilities
• 8 Interoperability demonstrations
• Example NCAR CAM with MITgcm ocean
• Multiple time scales
• NWP, mid-range forecast experiments
• Coupled seasonal forecasts
• Interannual/decadal variability
• Centennial simulations
• Will require tuning and validation to be
  scientifically useful

12
Development Plan

• Requirements
• Intensive interaction involving ESMF
  collaborators and broader community, ESMF
  Community Requirements Meeting
• High-level results presented in General
  Requirements Document, detailed requirements
  documents prepared later
• Design
• Design study includes examination of FMS, GEMS,
  MCT, and other existing Earth science frameworks
• Results presented in Architecture Report,
  detailed design documents for specific components
  prepared later
• Community review of ESMF interface specification

13
Development Plan, cont.

• Implementation
• Implementation study will determine
  implementation language, language
  interoperability strategy, programming model
• Examine viability of supporting software tools,
  e.g. CCA, Cactus
• Results presented in Implementation Report
• Best Practices
• Early distribution of Software Developers Guide
  will encourage consistent standards, conventions
  and practices throughout the project

14
Beyond 2004ESMF Evolution

• Maintenance and management
• NCAR commitment to maintain and support core ESMF
  software
• Persistence of ESMF Executive Committee and
  Advisory Board
• Technical evolution
• Functional extension support for advanced data
  assimilation algorithms, additional grids, new
  domains
• Earth System Modeling Environment, including
  web/GUI interface, databases of components and
  experiments, links to GRID services

15
Additional Information and Upcoming Events

• ESMF Community Requirements Discussion and Review
• Open Meeting
• In conjunction with the Spring
• American Geophysical Union Meeting
• May 30, 2002
• ESMF website http//www.esmf.ucar.edu
• Questions esmf_at_ucar.edu