Tools to interpolate spectral element grid to lat/lon grid
- Thread starter strandwg
- Start date
Hi Gary,
We don't have any shared scripts that remap entire cam-se history files to latitude longitude grids. We either just set the namelist variable that interpolates history fields in-line in cesm, or we use the available tools and build our own scripts for regridding individually. In response to this thread, I decided to make a simple bash script that can regrid an entire directory of history files in as few steps as possible. Unfortunately, the necessary nco command "ncremap" seems to have broken on cheyenne very recently. I just put in a CISL ticket, and when this is resolved I can update this thread.
There are two steps involved with regridding: (1) generate the weights file for mapping between two grids, and (2) use that weights file to regrid history files to the desired destination grid. I have (1) completed in the bash script, so we just need to wait on CISL so I can do (2).
Here's the caveat. To do (1), the user needs to specify the path to the grid descriptor file for the particular spectral-element grid the data are on. Right now the grid descriptor file is not part of the cesm output. We do have a git issue open to include this in cesm i/o in the future, but for now, the user needs to sift through the cesmdata repo to find the correct grid file. Similarly the user needs to point to the grid descriptor file for the desired destination lat-lon grid. The latter could conceivably be generated on the fly with the user only specifying the destination grid resolution nlat and nlon.
Feedback welcome.
We don't have any shared scripts that remap entire cam-se history files to latitude longitude grids. We either just set the namelist variable that interpolates history fields in-line in cesm, or we use the available tools and build our own scripts for regridding individually. In response to this thread, I decided to make a simple bash script that can regrid an entire directory of history files in as few steps as possible. Unfortunately, the necessary nco command "ncremap" seems to have broken on cheyenne very recently. I just put in a CISL ticket, and when this is resolved I can update this thread.
There are two steps involved with regridding: (1) generate the weights file for mapping between two grids, and (2) use that weights file to regrid history files to the desired destination grid. I have (1) completed in the bash script, so we just need to wait on CISL so I can do (2).
Here's the caveat. To do (1), the user needs to specify the path to the grid descriptor file for the particular spectral-element grid the data are on. Right now the grid descriptor file is not part of the cesm output. We do have a git issue open to include this in cesm i/o in the future, but for now, the user needs to sift through the cesmdata repo to find the correct grid file. Similarly the user needs to point to the grid descriptor file for the desired destination lat-lon grid. The latter could conceivably be generated on the fly with the user only specifying the destination grid resolution nlat and nlon.
Feedback welcome.
OK we fixed the problem w/ ncremap and verified it works for cam history files. However I've never worked with timeseries format. Can you point me to an example timeseries file on glade so I can make sure it works?
FYI, I tried to find one in /glade/campaign/collections/cmip/CMIP6/timeseries-cmip6/ but I don't have permissions. I do have permissions one directory up /glade/campaign/collections/cmip/CMIP6/ oddly enough.
FYI, I tried to find one in /glade/campaign/collections/cmip/CMIP6/timeseries-cmip6/ but I don't have permissions. I do have permissions one directory up /glade/campaign/collections/cmip/CMIP6/ oddly enough.
Thanks - I'll play around with it a bit.
Hi @aherring, I am also trying to convert cam files to regular lat lon. Here is my file directory (/glade/work/maruf/cam/evspsbl_Amon_CESM1-CAM5-SE-HR_hist-1950_r1i1p1f1_gn_195001-201412.nc). I have a few confusions:
1. My cam file is source grid or a destination grid?
2. Do I need to change the path of CIME?
3. What is the best way to run bash script. I tried with qsub in casper but is shows the following error: qsub: request rejected as filter hook 'ompthreads' encountered an exception. Please inform Admin
Thanks!!
1. My cam file is source grid or a destination grid?
2. Do I need to change the path of CIME?
3. What is the best way to run bash script. I tried with qsub in casper but is shows the following error: qsub: request rejected as filter hook 'ompthreads' encountered an exception. Please inform Admin
Thanks!!