This is the Version 4.6 release of the WRF Model. This release includes all components of the system: WRF-ARW, WRF-Chem, and WRFDA.
Acknowledgements: We would like to thank Kasra Shamsaei (University of Nevada, Reno), Tim Juliano, Domingo Munoz-Esparza, Branko Kosovic (NCAR/RAL), Jun Tang (Amazon), RenChuanhua and Huangxin (Nanjing University), David Robertson (Rutgers University), Kasra Shamsaei (University of Nevada, Reno), Tim Juliano, Branko Kosovic (NCAR/RAL), Cristina Archer (UDEL), Yulong Ma(UDEL;GWA-MWF), Ahmad Vasel-Be-Hagh(Tennessee Technological University), Zhixiong Chen (Fujian Normal University, China),JJ Guerrette (NCAR/MMM, now at tomorrow.io), Deqin Li (Liaoning Meteorological Bureau of CMA), Cenlin He (NCAR), Joseph Olson (NOAA), Laura Fowler (NCAR), Sergey Osipov (KAUST), Daniel Wesloh (Penn State), Do Ngoc Khanh (Tokyo Institute of Technology), Jordan Schnell (NOAA), Soren Rasmussen and Ryan Cabell (NCAR),Parag Joshi and Katia Lamer (Brookhaven National Lab), and Ted Mansell (NOAA) for their contributions to this release.
New features in WRFV4.6
Physics
- Add revised MM5 surface layer scheme from the future shared MMM-physics repository. Detail
- Add new Tiedtke cumulus scheme from the future shared MMM-physics repository. Detail
- Add WSM6 microphysics scheme from the future shared MMM-physics repository. detail
- Add YSU PBL scheme from the future shared MMM-physics repository. Detail
- Add GWDO (gwd_opt=1) code from the future shared MMM-physics repository. Detail
- Add two options (slucm_distributed_drag and distributed_ahe_opt) to WRF SLUCM (sf_urban_physics = 1) so that spatially varying urban morphological parameters (building height, plan area index, frontal area index, roughness length for momentum, and displacement height) can be considered. Detail
- Add salinity effect in MM5 and revised MM5 surface layer schemes. The effect is lower the saturation vapor pressure over ocean by about 2%. Detail
- Add options for three new wind farm parameterizations and their ensembles to account for the individual and overlapping sub-grid wakes of wind turbines within a wind farm. It is recommended to use the new wind farm parameterizations, particularly for coarse resolution, high turbine density, and wind directions aligned with the turbine columns. Detail
- Add 3-moment option to NSSL microphysics scheme (for rain, graupel, and hail) (mp_physics=18). Changes to snow aggregation parameters reduce stratiform reflectivity bias. Also add namelist options to enable/disable bulk CCN prediction and graupel/hail density prediction, and deprecate old mp_physics options (17, 19, 21, 22). Main default parameter changes are for graupel/hail fall speed options (icdx, icdxhl; changed from 3 to 6), and default maximum gr/hail droplet collection efficiencies (ehw0/ehlw0 changed from 0.5/0.75 to 0.9/0.9) See doc/README.NSSLmp for details. A problem is fixed for high resolution vertical domains with nz > 128, where hydrometeor sedimentation did not work at k > 128 (this bug affected most or all previous releases). Detail
Real-Data initialization
- Add a new namelist option "use_sh_qv = T" to allow for choosing to use SH or Qv data directly. If water mixing ratio or specific humidity is available in the metgrid output, they can be used directly in vertical interpolation. Previously these fields are first converted to RH, interpolated vertically, and the water vapor mixing ratio is computed at model levels.Detail
Data assimilation
- Add the capability for assimilating GOES-ABI radiance data. Detail
- Add a lightning data assimilation scheme to assimilate pseudo vertical velocity, divergence fields, or water vapor retrievals from lightning flash rate data. Detail
- Add a background-dependent hydrometeor retrieval scheme for indirect radar reflectivity assimilation. Detail
WRF-FIRE
- Add Scott and Burgan (2005) 40 fuel models for WRF-Fire. Detail
- Add a new Truncated Gaussian scheme to distribute fire heat and smoke in the atmosphere. Detail.
Chemistry
- Add WRF-SoilN-chem, a dynamic ammonia emission model capable of calculating NH3 emission rate interactively with time- and spatial-varying meteorological and soil conditions. Detail
Compiling
- Introduce a CMake build system for em_real and em_ideal as an optional compilation method. Detail. Users are welcome to try and provide feedback.
- Add CMake build option to WRF-Hydro. General bug fixes and code cleanup are also done. MPI routine is more efficient. All hydro file suffixes are now .F90. Detail
Bug fixes and enhancement in WRFV4.6
Physics
- Correct net long wave fluxes for application in modeling urban climate using Single Layer Urban Canopy Model (SLUCM). It slightly improved 2-m temperature in urban area. Details
- Change the behavior of the mp_zero_out flag so that it affects only the 'moist' array, whereas previously it also caused the scalar/chem/tracer arrays to also be set to zero for values below threshold. Now there is a separate flag (mp_zero_out_all) if one wishes to reproduce the old behavior. Details
- Move the call to shalwater_init from module_sf_sfclayrev.F to module_physics_init.F. This is in preparation to make sfclayrev module ccpp-compliant, and potentially make the initialization and physics available to other surface layer modules. Detail
- Fix a bug in Noah-MP for uninitialized leaf mass when LCZ is used. Detail
- Update urban LCZ parameter table (URBPARM_LCZ.TBL) with more reasonable values. Detail
- Update MYNN-EDMF . Detail
- Fix bugs in Noah-MP for snow combination, vegetation fraction scaling, and urban ground heat flux sign. Detail
- Remove zero negative latent heat flux limit (atmosphere to water) in the revised MM5 and original MM5 surface layer schemes. Detail
- Make the Pleim-Xiu LSM compatible with MODIS LCZ. Also, effects of evaporation from transpiration, soil in both vegetated and non-veg parts and wet leaves on ground temperature all are considered. Previously only the effect from transpiration and evaporation from non-veg soil are considered. Detail
- Modify the RUC LSM to add options to the snow model, use real-time vegetation fraction as an indicator for irrigation scheme, and change soil diffusional and hydraulic conductivities. Detail
- Correct diffusion coefficients for tke in LES. Detail
Chemistry
- A building issues with Intel compilers (ifx/icx) for WRF/WRF-chem is addressed. Detail
- Add KPP configure option for alternative libfl name, libfl.so, in addition to libfl.a. Detail
- Fix n2o5 heterogenous namelist option for MADE schemes. Detail
- A bug was introduced after splitting chem_opt 100 and 106. Currently, the chemistry initialization always calls for module_aerosol_soa_vbs routine, leaving the module_aerosol_soa_vbs_HET and corresponding data constants unitialized. As a result, aerosol concentrations are set to 0 after the first time integration (10**-16). This bug is fixed by Differentiate between module_aerosol_soa_vbs and module_aerosol_soa_vbs_het initialization routines. Detail
- Update the registry description for settling velocity of bin 5 for GOCART. Detail
Data assimilation
- Change an existing HDF5 lib name and add additional HDF5 libs to make sure WRFDA can be compiled in NCAR HPC Derecho when including RTTOV lib with HDF5. Detail
- Fix Bufrlib C code to ensure that WRFDA can be built with intel oneAPI compiler. A run-time segfault bug is also fixed. Detail
Compiling
- Add error checks in registry to catch code generation failure. Detail
- Add the ability for registry code generation to be out of source. Detail
- Fix missing or erroneous dependencies in make rules. Detail
- Fix a compiling issue on Cygwin. Detail
- Some versions of make appear to fail on the USENETCDFPAR logic in the top level Makefile if the variable is undefined. Thais issue is fixed by making sure it is at least set to 0 by the configure script fixes the issue. Detail
- Many files are generated in the repo's directories and should be ignored to avoid accidental addition to commits.Detail
- Update g2lib png encode/decode to use correct png_voidp define. Detail
- Fix bugs in gen_allocs to use correct conditional compilation logic on allocatables vs pointers. Detail
- Remove redundant code files wrf_status_codes.h, wrf_io_flags.h, io_int_idx_tags.h. Detail
- Fix issue with generalized compiler version output using the wrong flags. Detail
Miscellaneous
- Fix erroneous syntax in dyn_em/module_first_rk_step_part1.F. Detail
- Loop order is rearranged (permute) to help memory access; it also breaks down larger loops into smaller ones to allow partial vectorization (GCC). [Detail](loop order (permute) to help memory access; it also breaks down larger loops into smaller ones to allow partial vectorization (GCC))
- Adjust #defines to accommodate future CMake build. Detail
- Add a print for parameters used when running real.exe using auto_levels_opt = 2 option, which is the default. Details