CMOR 3.9.0

Features

• Added the functions cmor_set_quantize and cmor_set_zstandard for exposing the data quantization and Zstandard compression utilities of the netCDF library since version 4.9.0.
• MacOS arm64 builds for use on Apple silicon (M-series CPUs).

Bugfixes

• The attribute realm will not be written to files if it is not specified in the required_global_attributes of a controlled vocabulary.

Changes

• End of support for Python 3.8.
• Compatibility with the Numpy 2.0 C API.
• Use netCDF's default chunking rather than setting chunk size to 1 for coordinates/axis such as time to enhance performance of reading netCDF variables.

Closed Issues

• Exposing latest netcdf 4.9.x library functionality: quantize, zstandard (#725)
• arm64 build (#663)
• default realm = "REALM" is always written although not required by CV (#736)
• Numpy 2.0 compatibility issue (#742)
• Performance issues with small chunks (#601)