WRFV3.9.1 with ERA-Interim data on ORR2

Before trying to run WRF with ERA-Interim data, make sure you have completed the following:

    1. WPS: Use this as a template: namelist.wps, then run geogrid.exe to generate geo_em.d01.nc
    2. WPS: Copy the Vtable for ERA-Interim data into the WPS directory
      cp ungrib/Variable_Tables/Vtable.ERA-interim.ml Vtable

      Now link to your data files

      ./link_grib.csh ../../GRIB/ERAI/ERA

      and run ungrib.exe:

      [conor@orr2 WPS]$ ls -hl FILE*
      -rw-rw-r-- 1 conor conor 115M Mar 2 18:01 FILE:2017-12-01_12
      -rw-rw-r-- 1 conor conor 115M Mar 2 18:01 FILE:2017-12-01_18
      -rw-rw-r-- 1 conor conor 115M Mar 2 18:01 FILE:2017-12-02_00
      -rw-rw-r-- 1 conor conor 115M Mar 2 18:01 FILE:2017-12-02_06
      -rw-rw-r-- 1 conor conor 115M Mar 2 18:01 FILE:2017-12-02_12
      -rw-rw-r-- 1 conor conor 115M Mar 2 18:01 FILE:2017-12-02_18
      -rw-rw-r-- 1 conor conor 115M Mar 2 18:01 FILE:2017-12-03_00
      -rw-rw-r-- 1 conor conor 115M Mar 2 18:01 FILE:2017-12-03_06
      -rw-rw-r-- 1 conor conor 115M Mar 2 18:01 FILE:2017-12-03_12
    3. We need to convert the ERA-Interim data from model level to pressure levels. To do this, we need to create a file with information about the ERA-Interim model levels: (still in the WPS directory) create a file called ecmwf_coeffs file and put in the following data:
          0         0.000000    0.00000000
          1        20.000000    0.00000000
          2        38.425343    0.00000000
          3        63.647804    0.00000000
          4        95.636963    0.00000000
          5       134.483307    0.00000000
          6       180.584351    0.00000000
          7       234.779053    0.00000000
          8       298.495789    0.00000000
          9       373.971924    0.00000000
         10       464.618134    0.00000000
         11       575.651001    0.00000000
         12       713.218079    0.00000000
         13       883.660522    0.00000000
         14      1094.834717    0.00000000
         15      1356.474609    0.00000000
         16      1680.640259    0.00000000
         17      2082.273926    0.00000000
         18      2579.888672    0.00000000
         19      3196.421631    0.00000000
         20      3960.291504    0.00000000
         21      4906.708496    0.00000000
         22      6018.019531    0.00000000
         23      7306.631348    0.00000000
         24      8765.053711    0.00007582
         25     10376.126953    0.00046139
         26     12077.446289    0.00181516
         27     13775.325195    0.00508112
         28     15379.805664    0.01114291
         29     16819.474609    0.02067788
         30     18045.183594    0.03412116
         31     19027.695313    0.05169041
         32     19755.109375    0.07353383
         33     20222.205078    0.09967469
         34     20429.863281    0.13002251
         35     20384.480469    0.16438432
         36     20097.402344    0.20247594
         37     19584.330078    0.24393314
         38     18864.750000    0.28832296
         39     17961.357422    0.33515489
         40     16899.468750    0.38389215
         41     15706.447266    0.43396294
         42     14411.124023    0.48477158
         43     13043.218750    0.53570992
         44     11632.758789    0.58616841
         45     10209.500977    0.63554746
         46      8802.356445    0.68326861
         47      7438.803223    0.72878581
         48      6144.314941    0.77159661
         49      4941.778320    0.81125343
         50      3850.913330    0.84737492
         51      2887.696533    0.87965691
         52      2063.779785    0.90788388
         53      1385.912598    0.93194032
         54       855.361755    0.95182151
         55       467.333588    0.96764523
         56       210.393890    0.97966272
         57        65.889244    0.98827010
         58         7.367743    0.99401945
         59         0.000000    0.99763012
         60         0.000000    1.00000000
      

      Then copy the WRF conversion program into the WPS directory:

      cp ./util/calc_ecmwf_p.exe .

      and run it:

      ./calc_ecmwf_p.exe

      This should produce the files:

      [conor@orr2 WPS]$ ls -hl PRES*
      -rw-rw-r-- 1 conor conor 54M Mar 2 18:01 PRES:2017-12-01_12
      -rw-rw-r-- 1 conor conor 54M Mar 2 18:01 PRES:2017-12-01_18
      -rw-rw-r-- 1 conor conor 54M Mar 2 18:01 PRES:2017-12-02_00
      -rw-rw-r-- 1 conor conor 54M Mar 2 18:01 PRES:2017-12-02_06
      -rw-rw-r-- 1 conor conor 54M Mar 2 18:01 PRES:2017-12-02_12
      -rw-rw-r-- 1 conor conor 54M Mar 2 18:01 PRES:2017-12-02_18
      -rw-rw-r-- 1 conor conor 54M Mar 2 18:01 PRES:2017-12-03_00
      -rw-rw-r-- 1 conor conor 54M Mar 2 18:01 PRES:2017-12-03_06
      -rw-rw-r-- 1 conor conor 54M Mar 2 18:01 PRES:2017-12-03_12
      
    4. Run metgrid.exe, and you should see the following files:
      [conor@orr2 WPS]$ ls -hl met_em*
      -rw-rw-r-- 1 conor conor 13M Mar 2 18:01 met_em.d01.2017-12-01_12:00:00.nc
      -rw-rw-r-- 1 conor conor 13M Mar 2 18:01 met_em.d01.2017-12-01_18:00:00.nc
      -rw-rw-r-- 1 conor conor 13M Mar 2 18:01 met_em.d01.2017-12-02_00:00:00.nc
      -rw-rw-r-- 1 conor conor 13M Mar 2 18:01 met_em.d01.2017-12-02_06:00:00.nc
      -rw-rw-r-- 1 conor conor 13M Mar 2 18:01 met_em.d01.2017-12-02_12:00:00.nc
      -rw-rw-r-- 1 conor conor 13M Mar 2 18:01 met_em.d01.2017-12-02_18:00:00.nc
      -rw-rw-r-- 1 conor conor 13M Mar 2 18:01 met_em.d01.2017-12-03_00:00:00.nc
      -rw-rw-r-- 1 conor conor 13M Mar 2 18:01 met_em.d01.2017-12-03_06:00:00.nc
      -rw-rw-r-- 1 conor conor 13M Mar 2 18:01 met_em.d01.2017-12-03_12:00:00.nc
    5.  Change into your WRFV3/run directory and use this as a template: namelist.input. Copy or link the met_em files to your run directory, then run real.exe. You should get files like this:
      [conor@orr2 run]$ ls -hl wrfinput_d01 wrfbdy_d01 
      -rw-rw-r-- 1 conor conor  20M Mar  2 18:02 wrfbdy_d01
      -rw-rw-r-- 1 conor conor 8.6M Mar  2 18:02 wrfinput_d01
      
    6. Now run wrf: qsub RUN_WRF.qsub and you forecast should produce output files like this:
      [conor@orr2 run]$ ls -hl wrfout*
      -rw-rw-r-- 1 conor conor 395M Mar  2 18:05 wrfout_d01_2017-12-01_12:00:00
      

    Done!

Downloading ERA-Interim data for WRF

The ECMWF has a publicly accessible reanalysis dataset called ERA-Interim which can be used to run WRF. To download data for WRF, follow these steps:

  1. Go to the ECMWF website: https://www.ecmwf.int/ and click the “Log in” link in the top right-hand corner.
  2. If you already have an account, enter your username and password. If not, register by clicking “New users register here“. Fill in your name, UCD email address, Country: Ireland, Sector: Academic/Research. You will get an email with a link you need to click to confirm your application for an account. After a while you should receive another email with your ECMWF account details. Use these to log in, and change your password.
  3. We need three different types of data to run WRF:
    • Invariant data (things that don’t change)
    • Surface data
    • Model Level data
  4. We only need to download Invariant data once, which we can do here: http://apps.ecmwf.int/datasets/data/interim-full-invariant/. If you haven’t yet done so, click on “conditions of use”, fill in: Organisation: UCD, Organisation type: Academic/Research, Country: Ireland. If you agree with the conditions, click “Accept”. Select “Land-sea mask” and click “Retrieve GRIB”. Click “Retrieve now” on the next page, then you’ll see a page with the status of your request. When it changes from “queued” to “Download grib”, right-click on the download link and copy the link address. Open a terminal and ssh to the computer you will run WRF on (ORR2). If you need to, create a directory for this data. Mine is ~/GRIB/ERAI. Change into that directory, and use wget to download the data from the link you have copied. It will download with a strange name, like _mars-atls13-blahblah.grib, so move (mv) it to a sensible name, like ERA-Invariant.grib
  5. We need to download Surface data for each forecast date, which we can do here: http://apps.ecmwf.int/datasets/data/interim-full-daily/levtype=sfc/.
    • Select the month you want (I’m getting December 2017).
    • In the “Select Time” box, select all: 00:00:00 06:00:00 12:00:00 18:00:00
    • In the “Select Step” box, select zero: 0
    • In the “Select parameter” box, select the following:- 2 metre dewpoint temperature
      – 2 metre temperature
      – 10 metre U wind component
      – 10 metre V wind component
      – Mean sea level pressure
      – Sea surface temperature
      – Sea-ice cover
      – Skin temperature
      – Snow density
      – Snow depth
      – Soil temperature levels 1, 2, 3, 4
      – Surface pressure
      – Volumetric soil water layer 1, 2, 3, 4
    • Click on the “Retrieve GRIB” button, then click on “Retrieve now”. This will bring you to a status page. When your download is ready, copy the link, wget it to ORR2 ~/GRIB/ERAI/ and give it a sensible name, like: ERA-SFC-201712.grib
  6. Next we need the model level data, from here: http://apps.ecmwf.int/datasets/data/interim-full-daily/levtype=ml/. Select the same date, all times, and click on the following parameter names (which should tick all available levels):
    • Specific humidity
    • Temperature
    • U component of wind
    • V component of wind
      Then click on the “Retrieve GRIB” button, and “Retrieve now”. When the status of the request is complete, copy the “Download grib” link, wget to ORR2 and rename to something like: ERA-ML-201712.grib
      Finally, repeat the model level download procedure for one extra parameter, in a separate downloaded file:
    • Geopotential
      Download this file to ORR2 and rename to: ERA-MLZ-201712.grib

Your ERA-Interim files should now look something like this:

[conor@orr2 ERAI]$ ls -hl
total 346M
-rw-rw-r-- 1 conor conor 453K Mar 1 16:35 ERA-Invariant.grib
-rw-rw-r-- 1 conor conor 320M Mar 1 18:19 ERA-ML-201712.grib
-rw-rw-r-- 1 conor conor 1.4M Mar 2 13:12 ERA-MLZ-201712.grib
-rw-rw-r-- 1 conor conor 24M Mar 1 17:21 ERA-SFC-201712.grib