gaussain-reduced grid data
Added by fabien marnas over 7 years ago
Hello everyone.
I have been recently advised to use CDO, by a colleague suggesting this could solve my current problem.
In short, I need to manipulate meteorological fields (from GRIB files) over a gaussian-reduced grid. The requirements of the project are that we work only with the data at the gaussian-reduced grid coordinates, which means we need that no re-interpolation of the data over any regular grid is performed.
Different tools already tried, necessarily re-interpolate the data contained in the file over a regular 2D lat-lon grid.
I am not sure to find the right information about CDO in the documentation: is it possible to avoid this step (interpolation over regular grid) with CDO, in order to work over the original non-regular grid ?
Looking forward to hearing from you !
Best regards,
Fabien
Replies (5)
RE: gaussain-reduced grid data - Added by Uwe Schulzweida over 7 years ago
Hello Fabien,
Nearly all CDO operators are working on the original gaussian reduced grid. Only grid specific operators like the horizontal interpolation doesn't work directly on the gaussian grids.
Cheers,
Uwe
RE: gaussain-reduced grid data - Added by fabien marnas over 7 years ago
Dear Uwe,
thanks for your prompt answer !
If i understand well, there is also a python package for CDO? Can you confirm me that i could dump the data over the reduced grid using cdo tools within a python script, and then operates them in python ?
Cheers,
Fabien
RE: gaussain-reduced grid data - Added by Ralf Mueller over 7 years ago
for python usage, check Cdo{rbpy}
RE: gaussain-reduced grid data - Added by fabien marnas over 7 years ago
hello Ralf. thanks for the link.
One last confirmation: these numpy tools are then only usable with NetCDF files ?
i.e: I won't be able to use them to work on gaussian-reduced fields which will be under GRIB format ?
Best regards,
Fabien
RE: gaussain-reduced grid data - Added by Ralf Mueller over 7 years ago
Well, you could just convert it to netcdf, right? If you use the numpy stuff, the python bindings will do this for you.
on the other hand, there are other python libraries to read grib into numpy arrays. e.g. pyncl, grib_api/eccodes
hth
ralf