1. Recent Status of NEMS/NMMB- AQ Development Youhua Tang 1, Jeffery T. McQueen 2, Sarah Lu 1, Thomas L. Black 2, Zavisa Janjic 2, Mark D. Iredell 2, Carlos Pérez García-Pando 3, Oriol Jorba Casellas 3, Pius Lee 4, Daewon Byun 4, Paula M. Davidson 5, and Ivanka Stajner 6 1. Scientific Applications International Corporation 2. NOAA/NCEP/EMC 3. Barcelona Supercomputing Center, Edificio Nexus II c/ Jordi Girona 29, Barcelona, Spain 4. NOAA Air Resource Laboratory 5. Office of Science and Technology,NOAA/National Weather Service 6. Noblis Inc, Falls Church, VA

2. An inline model allows frequent interaction between meteorological and air quality processes. - Especially important for non-hydrostatic scales when meteorological features have fine temporal and spatial scales. This air quality model can be driven by different meteorological models (which can be on different grids, e.g. for quick testing) A common framework allows varying degrees of coupling and flexibility. Advantages of the ESMF Framework for Air Quality Application

3. Pros and Cons of the Inline Model Immediate and fast data access to the corresponding meteorological model. Overall efficiency by reducing the intermediate I/O files Can provide in-situ feedback to the met model Depends more on the met model than the offline version. Could slow down the meteorological forecast when running in the same domain

4. Analysis -------------- Ocean ------------- Wind Waves -------------- LSM -------------- Ens. Gen. -------------- Other 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

5. NEMS Atmosphere Atmospheric Model DynamicsPhysics and Chemistry Dyn-Phy Coupler NMM-B Spectral FIM Color Key Component class Coupler class Completed Instance Under Development NAM Phy GFS Phy Simple unified atmosphere including digital filter Future Development ARW FVCORE FISL NOGAPSWRF Phy Navy PhyCOAMPS Regrid, Redist, Chgvar, Avg, etc CMAQ Chemistry FVCORE: Finite-Volume Dynamical Core NOGAPS: Navy's Operational Global Atmospheric Prediction System COAMPS: Coupled Ocean/Atmosphere Mesoscale Prediction System NMM-B: Nonhydrostatic Multiscale Model on B grid FIM: Flow-following finite-volume Icosahedral Model FISL: Fully-Implicit Semi-Lagrangian GOCART Aerosol model Simple Chemistry

6. Two Inline Methods Meteorological Model Dynamics Physics Air Quality Model Dynamics Physics Chemistry Exchange data via the memory with specified time frequency A) B) Meteorological Model/Air Quality Model Dynamics with passive tracers Physics with AQ species Chemistry Meteorological I/O AQ I/O Unified I/O

7. Method A: Allows flexibility and can be made consistent Can keep most of the original AQM architecture with minimal changes. Different components can run on different grids supported by ESMF Inconsistencies may exist between meteorological and air quality models Overhead due to different dynamics/physics and diagnostic variables Method B: Focuses on efficiency and is inherently consistent All computation uses common native grid and dynamics High efficiency Low flexibility. Introduces dependency on certain meteorological dynamics or physics components Require positive-definite mass-consistent advection scheme and inclusion of AQ processes in the meteorological modules Pros and Cons of the two Methods in NEMS

8. MAIN Program MAIN Gridded Component INIT-RUN-FINALIZE Import State Export State DYNAMICS Gridded Component INIT-RUN-FINALIZE Chemical Initialization Lateral Boundary Conditions Chemical Advection Chemical Output Import State Export State PHYSICS Gridded Component INIT-RUN-FINALIZE Input Emissions Input Dry Depositions PBL Mixing (MYJ) Photolysis Calculation Chemical Reactions Convective Mixing Wet/Cloud Scavenging Import State Export State Dyn-Phys COUPLER Component INIT-RUN-FINALIZE Import State Export State General Output Gridded Component INIT-RUN-FINALIZE Import State Export State General Output Gridded Component INIT-RUN-FINALIZE Import State Export State Framework of NEMS/NMMB-AQ Method B

9. Coordinate System and Grid –Global lat-lon, regular grid –Regional rotated lat-lon, more uniform grid size –Arakawa B grid (in contrast to the WRF-NMM E grid) Pressure-sigma hybrid (Sangster 1960; Arakawa and Lamb 1977; Simmons and Burridge 1981) Flat coordinate surfaces at high altitudes where sigma problems worst (e.g. Simmons and Burridge, 1981) Higher vertical resolution over elevated terrain No discontinuities and internal boundary conditions –Lorenz vertical grid NMM-B Advection Scheme for Passive Tracers –Conservation through flux cancelations, not forced a posteriori –Quadratic conservative advection scheme coupled with continuity equation Crank-Nicholson for vertical advection Modified Adams-Bashforth for horizontal advection –Advection of square roots of tracers (c.f. Schneider, MWR 1984) provides positive definiteness –Quadratic conservation provides tracer mass conservation –Monotonization with a posteriori forced conservation to correct oversteepening NMM-B Dynamical Core

10. The NMM-B’s new scheme is shown to be mass conservative

11. Courtesy: Barcelona Supercomputing Center (BSC) Designated center within WMO Sand and Dust Storm Warning Advisory and Assessment System (SDS-WAS), NMM/BSC-DUST model

12. CMAQWRF-CHEMNMMB-AQ Model Framework CMAQWRFNEMS/ESMF Input Meteorology Offline, recalculate some variables, like w and PBL heights Inline Input frequency hourly Every advection time Step Advection scheme piecewise parabolic method WRF-ARW, WRF-NMM NMM-B PBL Mixing ACM2 (derived from input meteorology) Kz (calculated from YSU, MYJ etc) Inline MYJ Convective Mixing ACM (derived)Grell (derived) BMJ adjustment or Grell (derived) Gaseous Mechanism CB04, CB05, SAPRC RADM2, CBMZ, CB05, RACM CB05 Photolysis Look-up-table, Simplified TUV Fast-J, Fast-TUVTUV, Fast-TUV

13. NMMB Dry Run ONLY without convective mixing or wet scavenging

14. Solutions to avoid slowing down the Met forecast Run AQM on sub-domains Run AQM as a separate cycle from the operational Met model

15. Summary The development of NEMS/NMMB inline air quality model has started using ESMF framework Most of related chemical/physical modules are zero-dimensional or one dimensional, which can be placed into this system directly, either as normal subroutines or as an ESMF gridded component. We will use CMAQ existing chemical modules in this system. The new mass-conservative NMM-B advection scheme can support air quality applications.

16. Next steps for NEMS/NMMB-AQ development Add convective mixing for passive tracers Add in-cloud and under-cloud chemical scavenging. Replace interpolated emissions with native- grid emissions (CMAQ SMOKE package) Biogenic emission and Dry deposition inline Alternative more flexible coupling approach through a separate chemistry grid component (method A) will be explored Feedback case testing – leverage NEMS radiative interactions