WhatIs: the ioipsl library

The IOIPSL (for Input Output IPSL) library is a library used by LMDZ to read in input parameters (from the run.def text file and related *.def files) and write output NetCDF files (histmth.nc, histins.nc, etc.) at runtime.

Note that when running in parallel (MPI), each process will generate each its own set of output files: histmth_0000.nc, histins_0000.nc, etc. for process number 0, histmth_0001.nc, histins_0001.nc, etc. for process number 1, and so on. Once the run is finished it is up to the user to recombine these hist*_*.nc files into single files gathering the data over the entire planet, using the IOIPSL rebuild script, e.g.:

rebuild histmth.nc histmth_*.nc

Although still quite functional, use of IOIPSL to generate output files is now depreciated in favor of the XIOS library.

15/11/2021