gwf-ncar-conus_ii

NCAR-GWF WRF-CONUSII Simulation Outputs

In this file, the details of the dataset is explained.

Warning

It must be noted that the WRF-CONUSII dataset are in .tar format and the script untars the files automatically.

Caution

WRF-CONUSII dataset needs extensive I/O operations in the cache directory. So, in case of submitting SLURM jobs, it is recommended to use the $SLURM_TMPDIR directory as cache. This can be provided to the main extract-dataset.sh script using the --cache='$SLURM_TMPDIR' option. Please be mindful of single quotation marks for the argument.

Location of Dataset Files

The WRF-CONUSII simulation outputs are located under the following directories accessible from Compute Canada (CC) Graham Cluster:

/project/rpp-kshook/Model_Output/wrf-conus/CONUSII/hist # years 1995-2015
/project/rpp-kshook/Model_Output/wrf-conus/CONUSII/fut  # years 2080-2100

and the structure of the dataset hourly files is as following:

/project/rpp-kshook/Model_Output/wrf-conus/CONUSII/hist
├── 1995
│   ├── wrf2d_conusii_19950101.tar
│   ├── wrf2d_conusii_19950102.tar
│   ├── .
│   ├── .
│   ├── .
│   └── wrf2d_conusii_19951231.tar
.
.
.
├── %Y
│   ├── wrf2d_conusii_%Y%m%d.tar
│   ├── .
│   ├── .
│   ├── .
│   .
│   .
│   .
.
.
.
└── 2015
    ├── .
    ├── .
    ├── .
    └── wrf2d_conusii_20151231.tar

And, each .tar file has the following structure of content:

foo@bar:~$ tar --strip-components=5 -xvf wrf2d_conusii_%Y%m%d.tar > /dev/null
/path/to/tar/extracted/files
└── %Y
    ├── wrf2d_d01_%Y-%m-%d_00:00:00
    .
    .
    .
    └── wrf2d_d01_%Y-%m-%d_23:00:00

Coordinate Variables and Time-stamps

Coordinate Variables

The coordinate variables of the WRF-CONUSII simulations are located outside of the main dataset files. The NetCDF file containing the coordinate varibles could be found at the following:

/project/rpp-kshook/Model_Output/wrf-conus/CONUSII/hist/wrf04km_coord.nc

However, upon many trials by the author, the variables were not concatenated with the main NetCDF files easily. A workaround has been provided to add at least two necessary coordinate variables, i.e., XLAT and XLONG, to the WRF simulation files. These two coordinates are enough to work with almost all of the meteorological variables included in the dataset. The following scripts are used on Compute Canada (CC) Graham Cluster to produce the substitute NetCDF file containing coordinate variables:

# make a copy of coordinate variable NetCDF file first!
foo@bar:~$ module load cdo/2.0.4; module load nco/5.0.6; # load necessary modules
foo@bar:~$ coordFile="/project/rpp-kshook/Model_Output/wrf-conus/CONUSII/hist/wrf04km_coord.nc"
foo@bar:~$ ncks -v XLAT,XLONG "$coordFile" coord.nc
foo@bar:~$ nccopy -4 coord.nc coord_new.nc
foo@bar:~$ ncatted -O -a FieldType,XLAT,d,, coord_new.nc
foo@bar:~$ ncatted -O -a MemoryOrder,XLAT,d,, coord_new.nc
foo@bar:~$ ncatted -O -a stagger,XLAT,d,, coord_new.nc
foo@bar:~$ ncatted -O -a coordinates,XLAT,d,, coord_new.nc 
foo@bar:~$ ncatted -O -a FieldType,XLONG,d,, coord_new.nc
foo@bar:~$ ncatted -O -a MemoryOrder,XLONG,d,, coord_new.nc
foo@bar:~$ ncatted -O -a stagger,XLONG,d,, coord_new.nc
foo@bar:~$ ncatted -O -a coordinates,XLONG,d,, coord_new.nc
foo@bar:~$ ncwa -O -a Time coord_new.nc coord_new.nc
foo@bar:~$ ncrename -a XLONG@description,long_name coord_new.nc
foo@bar:~$ ncrename -a XLAT@description,long_name coord_new.nc
foo@bar:~$ ncatted -O -a cell_methods,,d,, coord_new.nc
foo@bar:~$ ncatted -O -a cell_methods,,d,, coord_new.nc
foo@bar:~$ ncatted -O -a ,global,d,, coord_new.nc
foo@bar:~$ ncatted -O -h -a license,global,c,c,"GNU General Public License v3 (GPLv3)" coord_new.nc

Furthermore, the substitute NetCDF file containing the coordinate variables are located at /asset/coord_XLAT_XLONG_conus_i.nc within this repository. The workaround NetCDF is automatically being used by the script to add the XLAT and XLONG variables to the final, produced files.

Time-stamps

Each hourly, extracted NetCDF files from .tar files will have a single time-stamp indicating the time-step of the file.

Dataset Variables

The NetCDF files of the dataset contain 187 variables. You may see a list of variables by using the ncdump -h command on one of the files:

foo@bar:~$ module load cdo/2.0.4
foo@bar:~$ module load nco/5.0.6
foo@bar:~$ ncdump -h  /path/to/extracted/conusii/netcdf/file.nc

Spatial Extent

The spatial extent of the WRF-CONUSII is on latitutes from 15.02852 to 73.27542 and longitudes from -156.8242 to -40.3046.

Temporal Extent

As is obvious from the nomenclature of the dataset files, the time-steps are hourly covering from the January 1995 to December 2015 (hist dataset directory). Also, the dataset covers data from January 2080 to December 2100 (fut dataset directory).

Short Description on WRF-CONUSII Variables

In most hydrological modelling applications, usually 7 variables are needed detailed as following: 1) specific humidity at 2 meters, 2) surface pressure, 3) air temperature at 2 meters, 4) wind speed at 10 meters, 5) precipitation, 6) downward short wave radiation, and 7) downward long wave radiation. These variables are available through WRF-CONUSII dataset and their details are described in the table below:

Variable Name	WRF-CONUSII Variable	Unit	IPCC abbreviation	Comments
surface pressure	PSFC	Pa	ps
specific humidity @2m	Q2	1	huss
air tempreature @2m	T2	k	tas
wind speed @10m	U10,V10	m/s	wspd	WIND=SQRT(U102+V102)
precipitation	PREC_ACC_NC	mm/hr		accumulated precipitation over one hour
short wave radiation	SWDOWN	W m-2	rsds
long wave radiation	GLW	W m-2	rlds