1. 1 The NOAA Environmental Modeling System at NCEP Thomas Black Mark Iredell Hann-Ming Henry Juang NOAA/ NWS/ NCEP/ Environmental Modeling Center 19 th Conference on Numerical Weather Prediction Omaha, NE 1 June 2009

2. 2 NEMS Team at EMC Hui-ya Chuang Edward Colón (Session 18, A.2) Dusan Jović Sarah Lu Shrinivas Moorthi Matt Pyle Ratko Vasić Jun Wang Wei-yu Yang

3. 3 Common Modeling Frameworks A model framework shared among developers offers potentially significant advantages if it lessens the difficulty of exchanging diverse codes and can unify their use/interactions efficiently. The framework should include global and regional models with separate components for dynamics, physics, data assimilation, post-processing, and ensemble capability for atmosphere, ocean, land, ice, and aerosols while adding minimal computational expense. In order to unify and streamline efforts within EMC and to enhance the ability to share packages developed elsewhere, construction of the new ESMF-based NEMS framework was undertaken.

4. 4 Why an ESMF-Based System? Now being used by a wide variety of developers. Offers considerable flexibility in how it is actually employed thereby also providing the opportunity to apply it in a manner that is not too difficult for users to understand. Undergoing continual development guided by direct user involvement. http://www.esmf.ucar.edu

5. 5 The integration portions of the GFS and NMM-B consist of coupled Dynamics and Physics subcomponents. Generic output components are in place for the NMM-B and in test phase for the GFS. NEMS-IO writes the final history/restart files. A common post-processor is available within the output components or as a stand alone process. Current NEMS Contents The forecast component of the Global Forecast System (GFS) and the Nonhydrostatic Multiscale Model (NMM-B) have been placed together under the single controlling layer.

6. 6 MAIN Program ATM Gridded Component INIT-RUN-FINALIZE Import State Export State DYNAMICS Gridded Component INIT-RUN-FINALIZE Import State Export State PHYSICS Gridded Component INIT-RUN-FINALIZE Import State Export State Dyn-Phys COUPLER Component INIT-RUN-FINALIZE Import State Export State Output Gridded Component 1 INIT-RUN-FINALIZE Import State Export State Output Gridded Component N INIT-RUN-FINALIZE Import State Export State Fundamental NEMS Structure

7. 7 Unified GFS-NAM Execution MAIN Program ATM/composite Gridded Component GFS-NAM Coupler Component ATM/NAM Gridded Component Physics Component Coupler Component Dynamics ComponentPhysics Component Coupler Component Dynamics Component ATM/GFS Gridded Component

8. 8 Coupled Forecast System Execution MAIN Program CFS Gridded Component ATM-MOM Coupler Component (may contain flux computations) OcnIce/MOM Component ATM Component Ice Component Coupler Component Ocean Component Land Component ATM-Land Coupler Component (may contain flux computations) NAM Component Coupler Component GFS Component

9. 9 Analysis -------------- Ocean ------------- Wind Waves -------------- LSM ---------------- Ens. Gen. -------------- Ecosystem -------------- Etc Physics (1,2,3) ESMF Utilities (clock, error handling, etc) Bias Corrector Post processor & Product Generator Verification Resolution change 1-1 1-2 1-3 2-1 2-2 2-3 ESMF Superstructure (component definitions, MPI communications, etc) Multi-component ensemble + Stochastic forcing Coupler1 Coupler2 Coupler3 Coupler4 Coupler5 Coupler6 Etc. Dynamics (1,2) Application Driver NOAA Environmental Modeling System (NEMS) (uses standard ESMF-compliant software) * Earth System Modeling Framework (NCAR/CISL, NASA/GMAO, Navy (NRL), NCEP/EMC, NOAA/GFDL) 2, 3 etc: NCEP-supported thru NUOPC, NASA, NCAR or NOAA institutional commitments Components are: Dynamics (spectral, FV, NMM, FIM, ARW, FISL, COAMPS…)/Physics (GFS, NRL, NCAR, GMAO, ESRL…) Atmospheric Model Chemistry

10. 10 Summary of Planned NEMS Capabilities (1) Components and capabilities of the NEMS infrastructure –Configuration control Domain Resolution (horizontal, vertical) Standardized fixed field generation (NPS - topography, land use, etc) Tracer definition –Nesting (static and moving, telescoping, 1-way, 2-way) –Concurrent ensemble execution (single executable, multiple members) –Data assimilation (3D-Var and advanced techniques) –Model dynamics and physics (including WRF schemes) Atmosphere Ocean Land surface and hydrology Air Quality, aerosols, and trace gases –Post-processor

11. 11 Summary of Planned NEMS Capabilities (2) Operational Models –Global Forecast System GFS –Global Ensemble (GEFS) GFS FIM –North American (NAM), standard/on-demand nested apps (e.g. Fire Weather…) NMM –Short-range Ensemble (SREF) NMM ARW Physics diversity –High Resolution Window (HRW) NMM ARW –Rapid Refresh (RR) Ensemble ARW Dynamics + GSD physics NMM dynamics + NCEP physics –Aerosols GOCART –Land Surface & Hydrology (LIS) Noah & LIS –Hurricane (HUR) NMM for hurricanes HYCOM + Wavewatch –Ocean, waves and Seasonal Climate Forecast (CFS) GFS for climate MOM4 HYCOM-Wavewatch

12. 12 ► First operational application of NEMS planned for 4 th Quarter 2010 12 km NAM NMM-B 4 km CONUS Nest 4-6 km Alaska Nest

13. 13 Operational 12 km NAM Domain

14. 14 4 km CONUS Nest

15. 15 4-6 km Alaska Nest

16. 16 Status Report (1) Forecast Models –The same layer controls forecast component of GFS and the NMM-B with digital filter(s). –Eventually it will do so for coupled runs and ensembles (GEFS and SREF). –First operational implementation in 4 th quarter 2010: NAM with CONUS/Alaska nests. 3DVAR –Work has begun to include NCEP 3DVAR (GSI).

17. 17 Status Report (2) Post-Processor –Unified NCEP Post-processor is operational (stand alone). –Being placed within the output component of NEMS (4 th quarter 2010 for NAM). Output –Generic output components with parallel I/O nearing completion. –Creating such components permits overall generalization and optimization.

18. 18 Status Report (3) NOAA/GSD –Collaborating on placing the FIM (Finite-volume Icosahedral Model) under NEMS. NOAA/GFDL –Collaborating on making the MOM4 an ocean component in the coupled seasonal CFS (Climate Forecast System) and GFS. NASA/Goddard –Collaborating on Aerosols. –Collaborating on including LIS schemes.

19. 19 Summary ► NCEP/EMC is constructing NEMS as a single ESMF-based framework for its primary operational systems in order to unify and streamline their development and to expedite interaction with other developers throughout the community. ► The GFS and NMM-B have been placed together under NEMS with additional cores to follow. ► Collaboration is ongoing with other centers to promote the exchange of various modeling systems/packages.