Thursday, 16 July 2015

LFR reforecasts using 20CR and ERA-20C


20CR

The latest (recommended) version of the NOAA/CIRES Twentieth Century Global Reanalysis is Version 2c:
http://rda.ucar.edu/datasets/ds131.2/

I registered for an account, and downloaded data using "Data Access" > "Get a Subset"

Land cover and geometric height were downloaded from a different page:
http://rda.ucar.edu/datasets/ds131.1/index.html#sfol-wl-/data/ds131.1?g=2

Recommended data for WRF:

3D: Temp, U, V, HGT, RH
2D: Surface Pressure, MSLP, Skin Temp, 2mT, 2mRH, 10mU, 10mV


If the WRF model is going to be run with the Noah LSM model, then at least 2 levels of Soil Temperature and Soil Moisture are required.

Soil Height is recommended but not required. If Soil Height is supplied, then SOIL Temperatures and TSK can be adjusted to the WRF model terrain height.

Water equivalent snow depth (SNOW) is a nice field to have, but not required.

SEAICE is good to have for a high latitude winter case, but it is not required.

http://www2.mmm.ucar.edu/wrf/OnLineTutorial/Basics/UNGRIB/ungrib_req_fields.htm


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ERA-20C

ERA-20C is ECMWF's first atmospheric reanalysis of the 20th century, from 1900-2010. It assimilates observations of surface pressure and surface marine winds only.
http://www.ecmwf.int/en/research/climate-reanalysis/era-20c

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WRF

Latest version for WRF-ARW and WPS is V3.7:
http://www2.mmm.ucar.edu/wrf/users/wrfv3.7/wrf_model.html

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Run WRF with 20CR

Change into WPD directory and clean up any previous data:
rm geo_em* GRIBFILE.* met_em.* FILE\:* *.log

# module load netcdf/2014_10
Run goegrid.exe.


Link in the AWIP Vtable. I've written one called Vtable.20CRv2c based on Vtable.NARR. Differences:

use SPECHUMD at 2m
PMSL GRIB = 2
ST GRIB = 11
SOILHGT GRIB = 8

ln -sf ungrib/Variable_Tables/Vtable.20CRv2c Vtable

Link-in the GRIB data.
ls
./link_grib.csh ../../../DATA/20CRv2c/

Edit namelist.wps.
start_date = '1910-05-20_06:00:00',
end_date   = '1910-05-21_06:00:00',
...
 e_we              =  67,
 e_sn              =  54,
 geog_data_res     = '10m',
 dx = 50000,
 dy = 50000,
 map_proj = 'lambert',
 ref_lat   =  48.049,
 ref_lon   =  8.07,
 truelat1  =  50.0,
 truelat2  =  46.0,
 stand_lon =  8.0,
...

Run
./ungrib.exe

Run
# module load netcdf-fortran/4.4.1 
./metgrid.exe

Change into WRF directory. Clean up any old data.
cd ../WRFV3p7/run
rm met_em.* wrfinput_* wrfbdy_* namelist.output wrfout_* rsl.*

Link-in the met_em files created with metgrid.exe
ln -sf ../../WPS/met_em.* .

check namelist.input. Run real.exe. Check that the following two files have been created:
wrfinput_d01
wrfbdy_d01

Run wrf.exe. Check that the following file has been created:
wrfout_d01_2000-01-24_12:00:00

xxxx

I should check out my old work files on metstore:

/store/CONOR/BACKUP/Code/WRF/WRF-20CRV2

xxxx