source: lmdz_wrf/trunk/WRFV3/README.NMM @ 2795

WRF-NMM Model Version 3.2 (March 31, 2010)

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WRF-NMM PUBLIC DOMAIN NOTICE
----------------------------

WRF-NMM was developed at National Centers for
Environmental Prediction (NCEP), which is part of
NOAA's National Weather Service.  As a government
entity, NCEP makes no proprietary claims, either
statutory or otherwise, to this version and release of
WRF-NMM and consider WRF-NMM to be in the public
domain for use by any person or entity for any purpose
without any fee or charge. NCEP requests that any WRF
user include this notice on any partial or full copies
of WRF-NMM. WRF-NMM is provided on an "AS IS" basis
and any warranties, either express or implied,
including but not limited to implied warranties of
non-infringement, originality, merchantability and
fitness for a particular purpose, are disclaimed. In
no event shall NOAA, NWS or NCEP be liable for any
damages, whatsoever, whether direct, indirect,
consequential or special, that arise out of or in
connection with the access, use or performance of
WRF-NMM, including infringement actions.

================================================

V3 Release Notes:
-----------------

This is the main directory for the WRF Version 3 source code release.

- For directions on compiling WRF for NMM, see below or the 
  WRF-NMM Users' Web page (http://www.dtcenter.org/wrf-nmm/users/)
- Read the README.namelist file in the run/ directory (or on 
  the WRF-NMM Users' page), and make changes carefully.

For questions, send mail to wrfhelp@ucar.edu

Release Notes:
-------------------

Version 3.2 is released on March 31, 2010.

- For more information on WRF V3.2 release, visit WRF-NMM Users home page
  http://www.dtcenter.org/wrf-nmm/users/, and read the online User's Guide.
- WRF V3 executable will work with V3.1 wrfinput/wrfbdy.  As 
  always, rerunning the new programs is recommended.

The Online User's Guide has also been updated.
================================================

The ./compile script at the top level allows for easy selection of 
NMM and ARW cores of WRF at compile time. 

   - Specify your WRF-NMM option by setting the appropriate environment variable:

         setenv WRF_NMM_CORE 1
           setenv WRF_NMM_NEST 1 (if nesting capability is desired)
         setenv HWRF 1 (if HWRF coupling/physics are desired)

   - The Registry files for NMM and ARW are not integrated
     yet. There are separate versions:

         Registry/Registry.NMM         <-- for NMM
           Registry/Registry.NMM_NEST    <-- for NMM with nesting
         Registry/Registry.EM          <-- for ARW (formerly known as Eulerian Mass)


How to configure, compile and run?
----------------------------------

- In WRFV3 directory, type:

   configure

  this will create a configure.wrf file that has appropriate compile 
  options for the supported computers. Edit your configure.wrf file as needed.

  Note: WRF requires netCDF library. If your netCDF library is installed in
        some odd directory, set environment variable NETCDF before you type
        'configure'. For example: 

        setenv NETCDF /usr/local/lib32/r4i4

- Type: 
        compile nmm_real
       
- If sucessful, this command will create nmm_real.exe and wrf.exe
  in directory main/, and the appropriate executables will be linked into
  the run directories under test/nmm_real, or run/.

- cd to the appropriate test or run directory to run "nmm_real.exe" and "wrf.exe".

- Place files from WPS (met_nmm.*, geo_nmm_nest*)
  in the appropriate directory, type

  real_nmm.exe

  to produce wrfbdy_d01 and wrfinput_d01. Then type

  wrf.exe

  to run.

- If you use mpich, type

  mpirun -np number-of-processors wrf.exe

=============================================================================

What is in WRF-NMM V3.2?

* Dynamics:

  - The WRF-NMM model is a fully compressible, non-hydrostatic model with a
    hydrostatic option.

  - Supports One-way and two-way static and moving nests.

  - The terrain following hybrid pressure sigma vertical coordinate is used.

  - The grid staggering is the Arakawa E-grid.

  - The same time step is used for all terms.

  - Time stepping:
     - Horizontally propagating fast-waves: Forward-backward scheme
     - Veryically propagating sound waves: Implicit scheme

  - Advection (time):
     T,U,V:
      - Horizontal: The Adams-Bashforth scheme
      - Vertical:   The Crank-Nicholson scheme
     TKE, water species: Forward, flux-corrected (called every two timesteps)/Eulerian, Adams-Bashforth
     and Crank-Nicholson with monotonization.

  - Advection (space):
     T,U,V:
      - Horizontal: Energy and enstrophy conserving,
        quadratic conservative,second order

      - Vertical: Quadratic conservative,second order, implicit

      - Tracers (water species and TKE): upstream, positive definite, conservative antifiltering
        gradient restoration, optional, see next bullet.

      - Tracers (water species, TKE, and test tracer rrw): Eulerian with monotonization, coupled with
        continuity equation, conservative, positive definite, monotone, optional.  To turn on/off, set
        the logical switch "euler" in solve_nmm.F to .true./.false.  The monotonization parameter
        steep in subroutine mono should be in the range 0.96-1.0.  For most natural tracers steep=1.
        should be adequate.  Smaller values of steep are recommended for idealizaed tests with very
        steep gradients.  This option is available only with Ferrier microphysics.

  - Horizontal diffusion: Forward, second order "Smagorinsky-type"

  - Vertical Diffusion:
     See "Free atmosphere turbulence above surface layer" section
     in "Physics" section given in below.

  - Added a new highly-conservative passive advection scheme to v3.2

Added Operational Hurricane WRF (HWRF) components to v3.2. These enhancements include:
     - Vortex following moving nest for NMM
     - Ocean coupling (with POM)
     - Changes in diffusion coefficients
     - Modifications/additions to physics schemes (tuned for the tropics)
         - Updated existing SAS cumulus scheme
         - Updated existing GFS boundary layer scheme
         - Added new HWRF microphysics scheme         - Added new HWRF radiation scheme
     Please see the WRF for Hurricanes webpage for more details:
         http://www.dtcenter.org/HurrWRF/users


* Physics:

  - Explicit Microphysics: WRF Single Moment 5 and 6 class /
    Ferrier (Used operationally at NCEP.) / Thompson [a new version in 3.1] 
    / HWRF microphysics: (Used operationally at NCEP for HWRF)

  - Cumulus parameterization: Kain-Fritsch with shallow convection /
    Betts-Miller-Janjic (Used operationally at NCEP.)/ Grell-Devenyi ensemble
    / Simplified Arakawa-Schubert (Used operationally at NCEP for HWRF)

  - Free atmosphere turbulence above surface layer: Mellor-Yamada-Janjic (Used operationally at NCEP.)

  - Planetary boundary layer: YSU /  Mellor-Yamada-Janjic (Used operationally at NCEP.) 
    / NCEP Global Forecast System scheme (Used operationally at NCEP for HWRF)
    / GFS / Quasi-Normal Scale Elimination

  - Surface layer: Similarity theory scheme with viscous sublayers
    over both solid surfaces and water points (Janjic - Used operatinally at NCEP).
    / GFS / YSU / Quasi-Normal Scale Elimination / GFDL surface layer (Used operationally at NCEP for HWRF)

  - Soil model: Noah land-surface model (4-level - Used operationally at NCEP) /
    RUC LSM (6-level) / GFDL slab model (Used operationally at NCEP for HWRF)

  - Radiation:
    - Longwave radiation: GFDL Scheme  (Fels-Schwarzkopf) (Used 
      operationally at NCEP.) / Modified GFDL scheme (Used operationally 
      at NCEP for HWRF) / RRTM
    - Shortwave radiation: GFDL-scheme (Lacis-Hansen) (Used operationally 
      at NCEP.) / Modified GFDL shortwave (Used operationally at NCEP 
      for HWRF)/ Dudhia

  - Gravity wave drag with mountain wave blocking (Alpert; Kim and Arakawa)
  
  - Sea Surface temperature updates during long simulations

* WRF Software:

  - Hierarchical software architecture that insulates scientific code
    (Model Layer) from computer architecture (Driver Layer)
  -  Multi-level parallelism supporting distributed-memory (MPI)
  -  Active data registry: defines and manages model state fields, I/O,
    nesting, configuration, and numerous other aspects of WRF through a single file,
    called the Registry
  - Two-way nesting:
      Easy to extend: forcing and feedback of new fields specified by
        editing a single table in the Registry
      Efficient: 5-8% overhead on 64 processes of IBM
  - Enhanced I/O options:
      NetCDF and Parallel HDF5 formats
      Nine auxiliary input and history output streams separately controllable through the
       namelist
      Output file names and time-stamps specifiable through namelist
  -  Efficient execution on a range of computing platforms:
      IBM SP systems, (e.g. NCAR "bluevista","blueice","bluefire" Power5-based system)
      IBM Blue Gene
      SGI Origin and Altix
      Linux/Intel
         IA64 MPP (HP Superdome, SGI Altix, NCSA Teragrid systems)
         IA64 SMP
         x86_64 (e.g. TACC's "Ranger", NOAA/GSD "wJet" )
         PGI, Intel, Pathscale, gfortran, g95 compilers supported
      Sun Solaris (single threaded and SMP)
      Cray X1, X1e (vector), XT3/4 (Opteron)
      Mac Intel/ppc, PGI/ifort/g95
      NEC SX/8
      HP-UX
      Fujitsu VPP 5000
  - RSL_LITE: communication layer, scalable to very large domains, supports nesting.
  - I/O: NetCDF, parallel NetCDF (Argonne), HDF5, GRIB, raw binary, Quilting (asynchronous I/O)
, MCEL (coupling)
  - ESMF Time Management, including exact arithmetic for fractional
    time steps (no drift).
  - ESMF integration - WRF can be run as an ESMF component.
  -  Improved documentation, both on-line (web based browsing tools) and in-line
 
    (Model Layer) from computer architecture (Driver Layer)
  - Multi-level parallelism supporting shared-memory (OpenMP), distributed-memory (MPI), 
    and hybrid share/distributed modes of execution
  - Serial compilation can be used for single-domain runs but not for runs with
    nesting at this time.
  - Active data registry: defines and manages model state fields, I/O,
    configuration, and numerous other aspects of WRF through a single file, 
    called the Registry
  - Enhanced I/O options:
      NetCDF and Parallel HDF5 formats
      Five auxiliary history output streams separately controllable through the namelist
      Output file names and time-stamps specifiable through namelist

  - Testing: Various regression tests are performed on HP/Compaq systems at
    NCAR/MMM whenever a change is introduced into WRF cores. 

  - Efficient execution on a range of computing platforms:
      IBM SP systems, (e.g. NCAR "bluevista","blueice" and NCEP's "blue", Power4-based system)
      HP/Compaq Alpha/OSF workstation, SMP, and MPP systems (e.g. Pittsburgh 
         Supercomputing Center TCS)
      SGI Origin and Altix
      Linux/Intel
         IA64 MPP (HP Superdome, SGI Altix, NCSA Teragrid systems)
         IA64 SMP
         Pentium 3/4 SMP and SMP clusters (NOAA/FSL iJet system)
      PGI and Intel compilers supported
      Alpha Linux (NOAA/FSL Jet system)
      Sun Solaris (single threaded and SMP)
      Cray X1
      HP-UX
      Other ports under development:
         NEC SX/6
         Fujitsu VPP 5000
  - RSL_LITE: communication layer, scalable to very
    large domains 
  - ESMF Time Management, including exact arithmetic for fractional
    time steps (no drift); model start, stop, run length and I/O frequencies are
    now specified as times and time intervals 
  - Improved documentation, both on-line (web based browsing tools) and in-line

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