Sorry for reply late. Great thanks to all of you. I have tried m3stat and it failed. So it’s the problem of my python script. I think @barronh 's suggestion is right, and I will try it in the future. And I also suggest the python-ioapi method in this url netCDF Wrapper Library for Gridded I/O API-like files - PYTHON - CMAS CENTER FORUM, to whom may use python to create the ioapi emission file.