WRF Model Update
WRF model tar file has been updated to Version
3.3 on April 6, 2011. For known problems in V3.3, please click here.
WRF Pre-Processing System (WPS) has been updated to Version 3.3.
Note: The V3.3 WRF can use V3.2 (and V3.1) wrfinput and wrfbdy files. However there are fixes in V3.3 program real (see below), and one may benefit from the change if wrfinput and wrfbdy files are regenerated.
As always, be cautious when using new options.
If you are interested in seeing
how V3 has been tested, click here.
New in Version 3.3:
Physics:
- Cumulus and shallow convection parameterization options:
* Tiedtke scheme, with shallow convection and momemtum transport (contributed by Zhang and Wang of University of Hawaii. See Tiedtke, 1989, MWR; and Zhang, Wang and Hamilton, 2011, MWR, 139, 3489-3513)
* New SAS (Simplied Arakawa-Schubert Scheme) from GFS with shallow convection and momemtum transport. (contributed by Hong et al. of University of Yonsei, S. Korea. See Han and Pan, 2011, Weather and Forecasting, in press)
*
Zhang-McFarlane scheme from CESM (a climate model), with momentum transport, and shallow convection as a separate option (see below). (Contributed by PNNL**. See Zhang and McFarlane 1995, Atmosphere and Ocean).
* SAS is adapted for ARW in this release (thanks to Zhang and Wang of U. of Hawaii). Shallow convection is included. Momentum transport is not on.
* A new trigger function based on Ma and Tan (2009, Atmospheric Research) is added to Kain-Fritsch scheme. The new trigger tends to trigger less convection in weakly forced environment.
* University of Washington shallow convection (contributed by PNNL**. See Park of Bretherton, 2009, J. of Climate)
- Microphysics option:
* Stony-Brook University scheme (contributed by Lin and Colle. See Lin and Colle, MWR, 2011, in press). This is a 5-class scheme with riming intensity predicted to account for mixed-phase processes.
- Atmospheric radiation option:
* Goddard long- and short-wave scheme (contributed by Shi and Matsui of NASA Goddard Space Flight Center)
- PBL options:
* University of Washington (TKE) scheme. (Contributed by PNNL**. See Bretherton and Park 2009, J. of Climate)
* Total Energy-Mass Flux scheme (contributed by Angevine of NOAA)
- Surface layer physics option:
* TEMF option. Works with TEMF PBL only.
- Wind-farm (drag) parameterization (contributed by Fitch and Alok Gupta of University of Bergen, Norway) (see README.windturbine)
(** PNNL: Gustafson, Fast and Rasch)
Dynamics:
- Stochastic kinetic-energy backscatter scheme for perturbing forecasts (contributed by Berner of NCAR. See Shutts, 2005, QJRMS; Berner et al. 2011, MWR, 138, 1972-1995)
Initialization:
- One-way nested DFI (contributed by Hutchinson of WSI and Chen of IUM, China)
- If fdda, sst_update, all_ic_times are not requested, then non-boundary calculations are excluded for efficiency purpose in program real.
- A way to initialize inland lake temperature using diurnally averaged skin temp.
- Idealized tropical cyclone case (contributed by Bryan of NCAR)
Improvements and Bug fixes: (with the significant ones highlighted in bold font)
Physics:
Atmospheric Radiation:
- RRTMG longwave: Improvement for temperature in stratosphere. This is similar to the improvement put in RRTM in V3.2. Reinstall fixes for clear-sky in v3.2 with consistant data files.
- RRTMG long- and short-wave schemes are coupled with chemistry option.
- Old Goddard shortwave scheme: correct outgoing SW diagnostics at TOA.
- CAM radiation: restore aborts if there is an error.
- slope effect on radiation: correct a bug if not all domains are using the option.
Microphysics:
- Thompson microphysics: bug fix and updates (see notes released on 12/13/2010)
- Old Thompson scheme: this is removed
- Milbrandt scheme: updated and minor fixes:
* corrected latent heat constants in thermodynamic functions (ABi and ABw) for sublimation and evaporation
* properly initialized variables No_g and No_h
* changed max ice crystal size (fallspeed) to 5 mm (2 m s-1)
* imposed maximum ice number concentration of 1.e+7 m-3
* removed unused supersaturation reduction
- Morrison microphysics:
* Modification for coupling with WRF-Chem (predicted droplet number concentration) as an option
* Modify fallspeed below the lowest level of precipitation, which prevents potential for spurious accumulation of precipitation during sub-stepping for sedimentation
* Bug fix to latent heat release due to collisions of cloud ice with rain
- WDM5, WDM6: minor fixes
- Eta scheme: allow for interaction with cumulus detrained cloud
Cumulus:
- GD cumulus: minor fix for vertical shear calculation
- G3 cumulus: fix for vertical shear calculation and entrainment rate
Planetary boundary layer physics:
- MYJ: TKE_MYJ and EL_MYJ are renamed to TKE_PBL and EL_PBL
-
BouLac scheme: add PBL height diagnostics
- MYNN PBL: QKE (TKE at half levels) is now advected
- LES: add HFX to output
Surface physics:
- Noah LSM: allow seasonal roughness length changes, fix underground run-off.
- PX LSM: minor fix.
-
LANDUSE.TBL: correct some categories in MODIS part.
- tmn_update: fix for the case when adaptive time stepping option is used.
- Ocean mixed layer: limit mixing by layer-mean temperature.
Gravity Wave Drag: clean-up, minor fix, add diagnostic output
Nudging:
- obs-nudging: add mm5 method to surface obs nudging.
Single-Column Model (SCM):
- addition of surface and large-scale forcing
- not limited to use Noah LSM
Adaptive Time Stepping:
- additional horizontal stability control by using new namelist option 'target_hcfl'
- restore correct output times by using
namelist option 'adjust_output_times'.
Dynamics:
- Minor fix for pressure calculation in hydrostatic option.
- Fix the use of perturbaion Coriolis for open boundary condition.
Initialization/IO:
- If specific humidity (most datasets have RH) is processed by WPS 3.2 (and 3.2 only because it introduced a new data flag: flag_sh) and passed to program real, then it is possible that RH calculation is ignored, hence resulting in errors in WRF input file. This is corrected in V3.3.
- Fix for RH-to-mixing ratio calculation if 'rh2qv_wrt_liquid' is false (default is true).
- A new method to compute mixing ratio from RH is added. To use the new method, add namelist 'rh2qv_method = 2' in &domains. This method appears to compute a very slightly drier atmosphere (contributed by Wee of UCAR).
- Fix
vertical interpolation using log pressure (interp_type=2) near surface where extrapolation may be needed (thanks to Wee of UCAR for the report).
- Allow for microphysical variables in the input automatically if WPS processes them . It was a compile option before.
- Fix for surface pressure and 2 m mixing ratio in wrfinput: they are now consistent with input. Both are not used by the model, though.
- IO associated with restart: there were a couple of problems / issues as a result of V3.2 updates:
1. output frequencies for history (wrfout) and restart (wrfrst) after restart: if one would make the frequency longer, the first output it would write would have used the old frequency. This is due to the IO alarms written to wrfrst file. This can be corrected by using namelist 'override_restart_timers = .true.' in &time_control
2. there
is not a wrfout file at the start of a restart run - this is not an error, it is just a different behaviour from the new restart. Output can be forecd by using namelist option 'write_hist_at_0h_rst = .true.'.
Care must be taken when using namelist ''override_restart_timers': if you use fdda and sst_update, and if you restart at a time which is not a data time, then the restart run could be wrong because it may use the wrong data for fdda and sst_update.
Nesting:
- Correct global attributes in nested wrfout files if nest wrfinput is not used.
- Time-series output for a nest is created even if nest wrfinput is not used.
- reactivate 'time_to_move' option for moving nest.
namelist.input
- further improved namelist check and advisory prints
Software:
New Features:
- p-netCDF support for io quilting (contributed by Andrew Porter of Daresbury Lab, UK)
Improvements:
- Internal checks are added inside the configure script to determine 32-bit vs 64-bit options in the compilers so that they are consistent with the libraries (such as netCDF). Also see 'Known Problems and Fixes'.
- Improved error messages when using runtime IO.
