NCAR Command Language (NCL)


NCL is an interpreted language designed for scientific data analysis and visualization.


Note

  • You will be using NCL version 6.6.2, which includes all functions necessary for creating plots

  • We recommend using an existing sample script as template, and then modifying it to suit your needs, if you want to make modifications


Available NCL Scripts

Below are the pre-written sample scripts are available from your wrf/test/em_real directories, but can also be found in /glade/campaign/mmm/wmr/wrf_tutorial/WRF_NCL_scripts.


Scripts for Real-data Cases


CreateTracks.ncl

wrf_AdaptiveTime.ncl

wrf_cape.ncl

wrf_Cloud.ncl

wrf_Cross2D.ncl

wrf_CrossSection_1.ncl

wrf_CrossSection1.ncl

wrf_CrossSection_2.ncl

wrf_CrossSection2.ncl

wrf_CrossSection_3.ncl

wrf_CrossSection3.ncl

wrf_CrossSection_4.ncl

wrf_CrossSection4.ncl

wrf_CrossSection_add_smooth_terrain4.ncl

wrf_CrossSection_add_smooth_terrain.ncl

wrf_dbz1.ncl

wrf_dbz2.ncl

wrf_EtaLevels.ncl

wrf_eth.ncl

wrf_Height2.ncl

wrf_Height.ncl

wrf_helicity.ncl

wrf_meteo_1.ncl

wrf_meteo_2.ncl

wrf_meteo_3.ncl

wrf_meteo_4.ncl

wrf_meteo_5_limited_height.ncl

wrf_meteo_5.ncl

wrf_metgrid1.ncl

wrf_metgrid2.ncl

wrf_metgrid3.ncl

wrf_metgrid4.ncl

wrf_metgrid5.ncl

wrf_metgrid6.ncl

wrf_metgrid7.ncl

wrf_metgrid8.ncl

wrf_moving_nest.ncl

wrf_moving_nest_overlap.ncl

wrf_moving_nest_precip_2doms.ncl

wrf_moving_nest_precip.ncl

wrf_overlay_doms.ncl

wrf_Overlay.ncl

wrf_panel1-1.ncl

wrf_panel1-2.ncl

wrf_panel1.ncl

wrf_panel2-2.ncl

wrf_panel2.ncl

wrf_Precip2.ncl

wrf_Precip3.ncl

wrf_Precip_multi_files.ncl

wrf_PressureLevel1.ncl

wrf_PressureLevel2.ncl

wrf_PressureLevel3.ncl

wrf_pv.ncl

wrf_PW2.ncl

wrf_PW3.ncl

wrf_PW.ncl

wrf_SkewT1.ncl

wrf_SkewT2.ncl

wrf_SkewT3.ncl

wrf_SkewT4.ncl

wrf_SkewT5.ncl

wrf_SkewT.ncl

wrf_Surface1.ncl

wrf_Surface2.ncl

wrf_Surface3.ncl

wrf_Surface_multi_files_avg.ncl

wrf_Surface_multi_files.ncl

wrf.ts.ncl

wrf_updraft_helicity.ncl

wrf_wind_rose.ncl

wrf_wps_plot_all.ncl

wrf_wps_ter1.ncl

wrf_wps_ter2.ncl

wrf_wps_ter3.ncl

wrf_wps_ter4.ncl

wrf_wps_ter5.ncl

wrf_wps_ter6.ncl

wrf_Zoom.ncl

olr.ncl

get_wrf_file_dims.ncl

gWRF_merc.ncl

design_grids.ncl


For beginners wanting to plot a single wrf output file (wrfout*), the following scripts are recommended:

  • wrf_CrossSection_1.ncl

  • wrf_EtaLevels.ncl

  • wrf_Height.ncl

  • wrf_PressureLevel1.ncl

  • wrf_Surface1.ncl

  • wrf.ts.ncl


For beginners wanting to plot multiple wrf output file (wrfout*), the following scripts are recommended:

  • wrf_Precip_multi_files.ncl

  • wrf_Surface_multi_files




Scripts for Idealized Cases


wrf_BWave.ncl

wrf_Grav2x.ncl

wrf_Hill2d.ncl

wrf_QSS.ncl

wrf_Squall_2d_x.ncl

wrf_Squall_2d_y.ncl





Running an NCL Script


  1. Create your own script, or pick one from of the supplied scripts. If you start with a supplied script, most often all you need to do is change the input file, in this line:


    a = addfile("./wrfout_d01_2023-03-31_00:00:00 .nc","r")
    

    Note

    You do not need to change your filenames so that they have a trailing .nc. But KEEP the trailing .nc in the above line, as this is used as a file type communicator to NCL.



  2. Run the script


    ncl <script>
    

    The output depends on your setting of “type” in the scripts. See detailed running instructions from the WRF Online Tutorial.






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