windspharm

"windspharm is a Python package for performing computations on global wind fields in spherical geometry. It provides a high level interface for computations using spherical harmonics. windspharm is capable of computing the following quantities from an input vector wind:

• divergence
• vorticity (relative and absolute)
• streamfunction
• velocity potential
• irrotational and non-divergent components of the wind (Helmholtz decomposition)
• vector gradient of a scalar function
• triangular truncation of a scalar field
• magnitude (wind speed)

windspharm provides a user-friendly interface for vector wind computations on the sphere (e.g., divergence, streamfunction etc.). It is based on the pyspharm module. windspharm provides a replacement for the windfield package from CDAT.

Windspharm  only requires numpy and pyspharm (version 1.0.8 or higher), but for full functionality (meta-data interfaces) one or more of iris, xarray or the cdms2 module (from UV-CDAT is required. The setuptools package is required for installation. windspharm runs on Python 2 and 3."

https://github.com/ajdawson/windspharm

http://ajdawson.github.io/windspharm/

http://openresearchsoftware.metajnl.com/articles/10.5334/jors.129/