After using the run_combine.csh in CMAQ/POST, the new .nc file has the differnt time from the ACONC file

i want to combine the PM2.5 component into a total varible. so i use the “/home/hczuo/CMAQv5.4/POST/combine/scripts/run_combine.csh” to finish it . after successfully generate the new ACONC_combine file, i find the time varibe’s type has changed from the datetime64 to int64. just like this:


this is the original aconc file

The data type of the underlying file cannot be inferred from a to_dataframe call of an xarray.Dataset object. NetCDF files cannot carry variables with type “datetime”. At best, they can carry of CF-compliant definition of time that xarray translates to a datetime object… Even so, ACONC files from CMAQ do not carry have datetime variable.

Use ncdump -h to get the header information (or m3hdr) of each of these files. That will show the variables that the files actually have and the units that the file has them in.

The file that you call the “original aconc file” looks like it is some custom file, and I would not expect an output from combine to match it.

2 Likes

thank you so much. I have find out the problem: because of my mistake of using the wrong scripts to convert the TFLAG variable. Thanks again!!!