Here are packages I have written for processing climate data, together with tools I have found online for climate data analysis/visualization.
Python package hn2016_falwa: hn2016_falwa is a python package for implementing the local finite-amplitude Rossby wave activity diagnostic on climate data. This is an analysis technique I proposed in my Ph.D. dissertation. The package is under active maintenance and constantly being updated.
python-climate-data-processing: A collection of jupyter notebook tutorials (in python 3.6) on Fourier transform, spectral analysis on climate data and visualization using the Cartopy library.