The WRF model tar file has been updated to Version 3.5 on April 18, 2013. In order to upgrade to version 3.5, users can obtain a new copy of the code from the download page.

The WRF Pre-Processing System (WPS) has also been upgraded to Version 3.5.

Note: WRF V3.5 can use WRFV3 wrfinput and wrfbdy only if iso_temp is set to 0 K in namelist &dynamics. If this option already used, please leave it in. This is important as the default value for iso_temp has been changed from 0 to 200 K in V3.5. Rerunning the new programs is always recommended. Be cautious when using new options.

Also see 'Known Problems' in this release. If you are interested in seeing how V3 has been tested, click here.

WRF Version 3.5 new features, improvements and bug fixes

HWRF specific updates

• New Capabilities and bug fixes:
• Triple nest 27/9/3 km capability matching the 2013 operational HWRF
• New vortex tracking algorithms
• Revised nest/parent interpolation routines
• Ability to run with all microphysics schemes (preliminarily tested)
• Interoperability added - Tiedke cumulus scheme can be used with HWRF
• Capability to perform I/O in netCDF or binary format in both big- and little-endian platforms
• Miscellaneous bug fixes

General updates - improvements and bug fixes

New Physics

Microphysics options:

• CAM5.1 2-moment scheme: Interacts with WRF-Chem (Thanks to PNNL)
• Two NSSL 1-moment schemes (Thanks to T. Mansell of NSSL)

Deep and shallow cumulus options:

• Grell-Freitas ensemble scheme (manuscript coming soon): An improved GD scheme that attempts to smooth the transition to cloud-resolving scales as proposed by Arakawa et al. (2004)
• Global/Regional Integrated Modeling System (GRIMS) shallow scheme (Hong et al. 2013 APJAS; thanks to Songyou Hong, Junhong Lee and Jihyeon Jang of YSU)

PBL option:

• Grenier-Bretherton-McCaa PBL (Grenier and Bretherton 2001, MWR): Scheme has the same origin as UW PBL and tested for marine boundary layer (Thanks to Natelie Perlin of Oregon State University)

Land Surface Models:

• Community Land Model Version 4 (CLM4) from CAM (Oleson et al. 2010; Lawrence et al. 2010): CLM4 was developed at the National Center for Atmospheric Research with many external collaborators and represents a state-of-the-science land surface process model. It contains sophisticated treatment of biogeophysics, hydrology, biogeochemistry, and dynamic vegetation. In CLM4, the land surface in each model grid cell is characterized into five primary sub-grid land cover types (glacier, lake, wetland, urban, and vegetated). The vegetated sub-grid consists of up to 4 plant functional types (PFTs) that differ in physiology and structure. The WRF input land cover types are translated into the CLM4 PFTs through a look-up table. The CLM4 vertical structure includes a single-layer vegetation canopy, a five-layer snowpack, and a ten-layer soil column. An earlier version of CLM has been quantitatively evaluated within WRF in Jin and Wen (2012; JGR-Atmosphere), Lu and Kueppers (2012; JGR-Atmosphere), and Subin et al. (2011; Earth Interactions) (Thanks to Jiming Jin of Utah State University and Yaqiong Lu of UC Merced)
• University of Arizona snow physics for Noah: Treatment of snow related to vegetation canopy (Wang et al. 2010: Improving snow processes in the Noah land model, J. Geophys. Res., 115, D20108, doi:10.1029/2009JD013761). (Thanks to Xubin Zeng, University of Arizona; Zhuo Wang, NASA; Michael Barlage, NCAR)

WRF-Hydro:

• An initial suite of hydrological physics parameterizations to represent routing (horizontal movement) processes including, groundwater transport, overland flow and streamflow. It is also a coupling framework for coupling additional hydrologic and land surface models to WRF. For more information and code download, click here.

Others:

• Input to atmospheric radiation option: Time-varying green-house gases for CAM/RRTM/RRTMG longwave radiation options, contains values for 250 years from 1765 to 2500; future scenarios of A2, A1B, RCP4.6, 6 and 8.5 are provided (Thanks to Claire Carouge of UNSW, Australia, Luis Fita and Jesus Fernandez, Universidad de Cantabria, Spain, Rowan Fealy, National University of Ireland Maynooth)
• RRTMG: Options to use CAM ozone data (o3input = 2) and Tegen climatological aerosol (aer_opt = 1)
• topo_wind = 2: A simpler terrain-variance-related correction; it works for YSU PBL (Thanks to Cliff Mass and David Ovens of University of Washington)
• Seaice initialization: Option to use default value or read in from input file (ICEDEPTH); special input required (Thanks to Byrd Polar Research Center, The Ohio State University)
• Snow depth on seaice: Bounded by minimum and maximum (controlled by namelists), or read in from input SNOWSI; special input required (Thanks to Byrd Polar Research Center, The Ohio State University)
• PWP 3D ocean model with simple initialization (Thanks to Chiaying Lee and Shuyi Chen of Univ. of Miami)
• Option to use NSBD/NUDAPT data for urban options (Thanks to Tim Glotfelty and Jason Ching of NCSU)
• NLCD 2006 40-category data: Works for slab, Noah and Pleim-Xiu LSM (Thanks to Rob Gilliam and Jon Pleim of EPA)
• Lightning parameterization without WRF-Chem (Thanks to John Wong of CU)

Dynamics/Advection

Default temperauture value for reference state in the stratosphere has been changed from 0 to 200 K. This is to ensure reasonable reference state used when model top is higher than 50 hPa and will change how the eta levels are computed in program real. If you use wrfinput files produced by previous versions of the model, make sure you include iso_temp = 0 in the namelist &dynamics section.

Improvements and Bug Fixes

Physics:

Atmospheric Radiation
• FLG: Bug fix for low model top; aerosol off by default, and aerosol option requires input
• Goddard: Limited ice effective radius to between 25 and 125 um
• Constants used for RRTM radiation have been changed for CO2 from 330 to 379 ppm, N2O from 0 to 319 ppb, and CH4 from 0 to 1774 ppb. These constants are now the same as those used in RRTMG. This change will make lower atmosphere and surface slightly warmer.

Microphysics
• Thompson: Minor update; also fix for computing radar reflectivity
• Morrison: Corrected for too much ice in anvil cloud; for accelerated melting from collisions, should use rain mass collected by snow, not snow mass collected by rain
• WDM5 and WDM6: Limited rain and cloud number concentrations using smaller maximum and minimum slope parameter values; helps to reduce strong radar reflectivity and rain rates
• WDM6/WSM6: Fixes for time-step graupel calculation
• NSSL 2-moment: Bug fixes and sedimentation change

Cumulus
• CAMZM: Changed time-scale for CAPE removal (tau) from constant 3600 s to grid distance-dependent
• NSAS shallow: Bug fix which allows shallow convection to activate

Planetary Boundary Layer Physics
• BouLac: Added a Troen-Mahrt gamma term option
• MYJ PBL: Diagnosed PBL height corrected
• MYNN: Option to (not) advect qke (namelist bl_mynn_tkeadvect; thanks to Joe Olson of NOAA)

Surface Physics
• NoahMP: Improvements to energy balance and distribution of energy over vegetated/non-vegetated portions of a grid cell; thread the packing and unpacking of MPI messages (will improve performance of all dm+sm runs); special optimized version of WSM5; a couple of other miscellaneous performance modifications that should help on Xeon Sandybridge (SNB)
• Glacier physics separated from land physics for Noah and NoahMP
• Corrected parameters in SOILPARM.TBL (Thanks to Thanks to Peter Shellito of CU)
• RUC LSM: Bug fixes for coupling with YSU and MYNN; seasonal variations of land-surface properties; increased roughness length for forest and cropland to correct high-wind biases; use of exponential formulation to compute grid-cell averaged roughness length; fixes in frozon soil moisture transport
• SSiB: Fix for sea ice

Others
• Renamed namelist option: omlcall to sf_ocean_physics to accommodate more ocean options
• Renamed CAM routines: module_cam_camuwshcu_driver.F to module_shcu_camuwshcu_driver.F and module_cam_camuwshcu.F to module_shcu_camuwshcu.F
• Renamed fire routines

Nudging:

• Minor bug fix for gridded nudging

Stochastic Kinetic-Energy Backscatter Scheme:

• Perturbed BC using SKEBS (namelist option perturb_bdy)

Initialization/IO:

• Diagnostic output of output-interval maximum of surface wind, max up- and down-draft velocity, column-mean w (eta between 0.8 to 0.5), 2-5 km helicity, column-integrated graupel and max column-integrated graupel, activated by namelist option nwp_diagnostics (Thanks to NSSL)
• wrfbdy file name may be changed using the namelist option bdy_inname
• Restart fix: chanrval in restart with FDDA, sst_update
• Vertical profiles of U, V, geopotential height, potential temp, and water vapor mixing ratio; this is done the same as 2D time-series; more information in run/README.tslist (Thanks to Torge Lorenz from University Research in Bergen, Norway)
• Inline trajectory code for pre-specified parcels (Thanks to Chiaying Lee of University of Miami)
• ndown can produce mp variables in bc file, but WRF cannot use them yet - will update in WRFv3.5.1
• Grib 1 and 2 tables updated
• rsl files will be automatically removed before new ones are written

Namelist:

• All vertical levels in the namelist templates have been changed to 30 to accommodate minimum vertical layer thickness requirement when iso_temp is changed to 200 K

Software:

New Features
• Added netCDF4 compression capability (for more details, click here
• Fujitsu FX10 support (Thanks to Fujitsu)
• MIC support for new Intel Xeon Phi Many Integrated Core (MIC) architecture:
• Modified shared memory tiling algorithm so that tiles are calculated only once per zone per domain
• Threaded the packing and unpacking of MPI messages (will improve performance of all dm+sm runs)
• Special optimized version of WSM5
• Several other miscellaneous performance modifications helping on Xeon Sandybridge (SNB) processors (e.g., Yellowstone)

Improvements
• Improved OpenMP use (Thanks to many at Intel, Jeff McDonald and Todd Hutchinson of WSI, Pete Johnsen and James Schwarzmeier of Cray, and John Michalakes at NREL)
• Fixes to binary IO
• Fixed make dependency
• Updated diffwrf