Iris and Cartopy are open source Python libraries initially created by the Met Office to enable the visualisation of weather and climate data. Both libraries are actively developed in collaboration with the scientific community.

biggus provides arrays of arbitrary size, with arithmetic and statistical operations, and conversion to NumPy ndarrays.
cf_units is a wrapper class to support Unidata/UCAR UDUNITS-2, and the netcdftime calendar functionality. Provides units of measure.
iris-grib is a Python package for converting between GRIB files and Iris cubes.
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