Huge netcdf files handling
For processing large data it is a good practice to call data into RAM in slices(Either by spliting time axis or spatial domain). In the interest of earth sciences python packages Xarray, iris, netCDF4 and h5py are few of the great tools for handling huge hierarchical data. For handling data in a labeled fashion Xarray and Iris will be useful while netCDf4 and h5py are good to process in a gridded way.

My personal suggestion is h5py which is meant for processing and archiving large datasets. Documentation here explains it. If you have netcdf files and want them in hdf5 format a question at Stack Overflow might help.