I would like to use MPAS-JEDI to study other cases. I would like to know if I should use the restart.xxx.nc or history.xxx.nc file of MPAS for the first guess? In the MPAS-JEDI tutorial, I see that the restart.xxx.nc file is used, can both files be used for assimilation and then what is the difference between the two?
I would suggest using the ‘da_state’ stream to write initial guess files. In order to do so, you also need any “init.xxx.nc” file for the same mesh (can be from any time) to act as the “static” input file. An example is shown in this yaml: mpas-jedi/3denvar_2stream_bumploc_unsinterp.yaml at master · JCSDA/mpas-jedi · GitHub
If you would prefer to use a single stream input as the background (not da_state plus static), then you must use the restart input stream (and hence restart forecast files).