A fundamental requirement for the exchange of scientiﬁc data is the ability to precisely describe the physical quantities being represented. Therefore, special attention needs to be paid to the representation of the model data in the output ﬁles. We require data in the ‘Network Common Data Form’ (netCDF) that adhere to the netCDF Climate and Forecast (CF) metadata convention (if
possible to version 1.6 from Dec. 2011 ). All netCDF ﬁles should have the ﬁle name extension ‘.nc’. We specify details of the netCDF requirements in Appendix F of the DCMIP test case document (see Overview of Test Cases) and will also provide help via NCO operators before the DCMIP event to make the data CF-compliant if necessary. Please communicate your output constraints or concerns (if any) to the DCMIP organizers as soon as possible. We will also ask for example data sets before the DCMIP event.
A netCDF CF-compliance checker is installed on the NCAR machine mirage0.ucar.edu that has access to all /glade/... directories. The CF-compliance of the netCDF data set can be checked in the following way:
logon with your NCAR username and one-time password:
ssh -Y mirage0.ucar.edu
If your default shell is tcsh,execute:
If your defaulkt shell is bash, execute
Load the CF checker:
module load cfchecks
Change to your directory on the glade server where the data are located. Check the netCDF file:
This command checks the netCDF file for consistency and compliance with the CF standard.
INFO and WARNING messages are acceptable. ERROR messages require reformatting of the netCDF file via NCO operators (see below).
The complete documentation is provided on the page: http://nco.sourceforge.net/nco.html
Exclude variables from the netCDF file and create a new output file via ncks
Example: Create the netCDF file out.nc containing all variables and any associated coordinates, except (-x) the listed variables (-v), from the netCDF in.nc
ncks -h -x -v co2vmr,n2ovmr,isccp_prs,isccp_prstau,isccp_tau in.nc out.nc
Extract variable from a netCDF file via ncks
Example: Extract variables
PS from netCDF in.nc. If out.nc does not exist it will be created. Otherwise you will be prompted whether to append to or to overwrite out.nc. All relevant coordinate information will be kept.
ncks -h -v time,PS in.nc out.nc
DCMIP-2012: News Report on DCMIP
Check out the NCAR CISL News report http://www2.cisl.... More »
cjablono @ 09/20/2012 10:56 a.m.
DCMIP-2012: Photo Gallery
Check out the photos of the Saturday hike on the ... More »
cjablono @ 08/04/2012 5:12 p.m.
DCMIP-2012: Welcome & Ice Breaker Reception
Monday (7/30/2012) 4:30-6:30pm, NCAR Mesa Lab Tree Plaza More »
murphysj @ 07/27/2012 12:16 p.m.
DCMIP-2012: Pre-Workshop Informal Get-Together
Sunday (7/29/2012) at the Baker Street Pub & Grill near ... More »
murphysj @ 07/27/2012 12:13 p.m.