Downloading the input data
The input data and the namelists needed to run the experiments can be downloaded from the ECMWF server (login is not required). For further instructions, please visit the following website: http://download.ecmwf.int/test-data/openifs/reference_casestudies.
The files are packed in .tar.gz files and structured into directories named after the case studies (i.e. Xaver_201312, Desmond_201512) and subdirectories indicating the main experiment characteristics (e.g., T255L91_ERA5). Each archive file contains the data for a given starting date (e.g., gs0c_2015120300.tar.gz). Typical content of a .tar.gz file is as follows:
File name |
|
Description |
Size |
2015120300/ |
: |
directory for a given starting date |
0 MB |
2015120300/ecmwf/ |
: |
subdirectory containing the namelists and some outputs |
0 MB |
2015120300/ecmwf/namelistfc |
: |
namelist with detailed experiment setup |
4.6 KB |
2015120300/ecmwf/NODE.001_01.model.1 * |
: |
text output (log) file including all the important information about the model run |
3.8 MB |
2015120300/ecmwf/ifs.stat.model.1 * |
: |
information about model steps (useful for debugging) |
26 KB |
2015120300/ecmwf/wam_namelist |
: |
namelist of the coupled wave model |
3.1 KB |
2015120300/ICMCLgs0cINIT |
: |
input file containing surface and soil information (albedo, soil temperature etc.) |
9.3 MB |
2015120300/ICMGGgs0cINIT |
: |
input file containing gridpoint surface initial data |
7 MB |
2015120300/ICMSHgs0cINIT |
: |
input file containing initial data for the prognostic variables in spectral representation |
35 MB |
2015120300/ICMGGgs0cINIUA |
: |
input file containing initial data for the prognostic variables in gridpoint representation |
101 MB |
2015120300/wam_grid_tables |
: |
model grid and tables for the wave model |
52 MB |
2015120300/wam_subgrid_0 |
: |
information for model advection, including sub-grid parametrisation for the wave model |
12 MB |
2015120300/wam_subgrid_1 |
: |
information for model advection, including sub-grid parametrisation for the wave model |
25 MB |
2015120300/wam_subgrid_2 |
: |
information for model advection, including sub-grid parametrisation for the wave model |
25 MB |
2015120300/cdwavein |
: |
initial value of drag coefficient for the wave model |
63 KB |
2015120300/specwavein |
: |
initial wave spectra for the wave model |
7.6 MB |
2015120300/uwavein |
: |
initial value of wind speed for the wave model |
63 KB |
2015120300/sfcwindin |
: |
initial value of 10-meter horizontal wind components and sea ice fraction for the wave model |
2.2 MB |
*
NODE.001_01.model.1
and
ifs.stat.model.1
files are from an OpenIFS run at ECMWF and they are provided for comparison with the user run.
The namelist
The namelist file highlighted in green in the box above controls the necessary experiment settings (e.g., time step, experiment ID) as well as the post-processing. The most important namelist elements are listed below with their explanation:
&NAMDYN
! Name of the namelist group
TSTEP=2700.0, ! Time step in seconds
/
! End of the namelist group
&NAMFPG NFPLEV=91, ! Number of vertical levels
NFPMAX=255, !
Spectral truncation /
&NAMCT0 CNMEXP="gs0c", ! Experiment IDNFRPOS=4, ! Output frequency of the 'history' files
NFRHIS=4,
in time steps (i.e. here 3 hours)
!
in time steps (i.e. here 3 hours)
Output frequency of the model variables
/
&NAMFPC
! Pressure level outputs: number of fields (NFP3DFP), GRIB field codes (MFP3DFP) and pressure levels in Pascals (RFP3P) NFP3DFP=9, MFP3DFP(:)=129,130,135,138,155,157,133,131,132,
RFP3P(:)=100000.0,92500.0,85000.0,70000.0,50000.0,40000.0,30000.0,25000.0,20000.0,15000.0,10000.0,7000.0,5000.0,3000.0,2000.0,1000.0,700.0,500.0,300.0,200.0,100.0,
! Saving spectral orography (geopotential), surface
pressure (logarithm of surface pressure) needed for post-processing NFP2DF=2, MFP2DF(:)=129,152,
! Physics output: number of fields (NFPPHY) and GRIB field codes (MFPPHY)
NFPPHY=89,
MFPPHY(:)=31,32,33,34,35,36,37,38,39,40,41,42,44,45,49,50,57,58,59,78,79,129,136,137,139,141,142,143,144,145,146,147,148,151,159,164,165,166,167,168,169,170,172,175,176,177,178,179,180,181,182,183,186,187,188,189,195,196,197,198,201,202,205,206,208,209,210,211,235,236,238,243,244,245,229,230,231,232,213,212,8,9,228089,228090,228001,260121,260123,228129,228130,
/
&NAMFPD
NLAT=256,
Number of latitudes on the corresponding Gaussian grid
!
NLON=512,
Number of longitudes on the corresponding Gaussian grid
!
/
In the evaluation, we would like to investigate the following variables:
- mean sea level pressure: its code number is 151;
- 2-meter temperature: its GRIB code number is 167;
- precipitation: it is composed from large-scale and convective precipitation with code numbers 142 and 143, respectively;
- 10-meter wind gust: its code number is 49;
- temperature at 850 hPa level: its code number is 130;
- relative humidity at 700 hPa level: its code number is 157;
- geopotential at 500 hPa level: its code number is 129;
u and v wind components at 250 and 100 hPa with code numbers 131 and 132, respectively.
These variables have to be included in the namelist among the post-processing variables (see the code numbers and levels highlighted with characters in the box above).
More information about the namelist settings and GRIB field codes of different parameters can be found in the OpenIFS how-to articles: How to control OpenIFS. To run the model, the paths of the input data and the namelist have to be set in the job script. A sample job script is part of the OpenIFS distribution and the model execution is explained in detail at the OpenIFS installation page.