Introduction to WRF

The Advanced Research WRF (ARW-WRF) 歷經多年大氣學術社群及相關產業社群開發。WRF 模式堪稱一套靈活、最先進的 (最尖端的) 大氣模擬系統，在平行計算平台上運行高效且具可移植性。WRF 模式的應用範圍涵蓋各種尺度，從數公尺到大氣層的廣闊範圍皆能使用，在地理研究、氣候研究、天氣預報等領域發揮著重要作用。最新版本的原始碼可在 WRF GitHub Repository ( wrf-model/WRF ) 取得。

不僅如此，WRF 模式還允許使用者針對不同情境，選擇合適的物理參數化方案，例如地表模型、雲微物理方案、邊界層參數化方案和積雲參數化等，使模擬的结果更加貼近真實大氣狀況。

WRFV4.5+：

• A new package to compute two-moment prognostics for graupel/hail and a predicted density graupel category is added in the Thompson scheme (mp_physics=38). Other updates to the scheme include a change to the Y-intercept relationship for one-moment graupel and replacement of air temperature for wet-bulb temperature in riming and mixed phase processes (Jensen et al., in review). This code requires the datafile "qr_acr_qg_mp38V1.dat" to run, which can be found on the file system for the NCAR community HPC "Cheyenne" under /glade/work/wrfhelp/WRF_files/ and online at http://www2.mmm.ucar.edu/wrf/src/wrf_files/. Details

• A scale-aware or grid-distance-dependent option is added to the new Tiedtke scheme. The code is based on the paper by Wang (2022) with two minor changes removed. The option becomes active automatically when grid sizes is less than 15 km. PR1806 and PR1840

• A new k-epsilon-theta^2 PBL scheme, including two additional prognostic equations for dissipation rate and temperature variance, has been included in the WRF model (see Zonato et al.,2022:A New K–ε Turbulence Parameterization for Mesoscale Meteorological Models. Monthly Weather Review, DOI: https://doi.org/10.1175/MWR-D-21-0299.1). This scheme is designed for finer grids. It works with sfclay=2(time step = 90), sfclay=1(time step = 60), diff_opt=1, km_opt=4). Details

• Add support to build WRF on ARM64 (aarch64) architecture systems with the NVIDIA HPC SDK Compilers (nvfortran,nvc). Details

• Provided AMD AOCC Compiler support at the time of configuring WRF for AMD Architectures including Zen1, Zen2 and Zen3.

WRFV4.4+： 

• The capability to couple WRF and CMAQ (an air quality model developed at the US EPA) is added. As a coupled model, WRF-CMAQ can be run in a one-way fashion (i.e., meteorological information will be transferred to CMAQ directly to drive its calculation), or in a two-way fashion, (i.e., the aerosol information from CMAQ will be fed back to the RRTMG radiation physics in WRF). This is available beginning in WRFV4.4 and CMAQ v5.3.3.3. Refer to the EPA's WRF-CMAQ Model webpage for instructions. 

•   link   The ability to write compressed NetCDF4 files in parallel, via NetCDF V4.7.4+ is added. Performance is slower than pnetcdf, but can be notably faster than regular NetCDF on parallel file systems. As expected, compression provides files significantly smaller than pnetcdf generates.