Version 5.3.9 contains one major improvement and one bugfix. The default buffer size for all operators on classic files is 32 MiB. This will increase I/O speed in most cases. ncremap had a syntax error in a rarely used branch of code that caused Bash to emit scary messages even when the branch was not executed.

Version 5.3.8 contains fixes to ncclimo problems introduced with 5.3.7. The ncclimo "flexible-months" feature suffered from incorrect behavior for some inputs, and introduced a regression in seasonal filenames. The only new feature is that ncclimo now supports generating climos from high-frequency input data that are instantaneous (not mean) values. Documentation now reflects the new CF Convention Homepage URL.

Version 5.3.7 contains significant new features and fixes. ncremap support for MOAB-TempestRemap (mbtempest) has been refactored to optimize parallel weight generation and support new algorithms. ncclimo now supports "flexible-months", so input datsets can begin in an month, not just January. Additionally, ncclimo understands all consectutive 2-month pairs and 3-month trios as valid seasons. Other improvements include support for the l2d packing policy suggested for CMIP7, and for the NetCDF Expansion Pack v.1.5+ API, ncks fixes JSON-format output regressions, and ncclimo fixes automatic name generation fixes two corner case bugs.

Version 5.3.6 consists mainly of bugfixes: There is a regridder fix that prevent it from failing to work with some regional destination grids (global grids are not affected). ncclimo fixes an issue computing global timeseries from ELM/CLM data on unstructured grids, e.g., from "bigrid" ESM simulations. Smaller fixes abound, including to the map-checker. Regridder users should upgrade. Others may skip this release.

Version 5.3.5 contains mostly speed, robustness, and documentation improvements for the regridder. The ability to select alternate executable and library paths for testing snapshots is also improved. Skip this release if these changes do not interest you.

Version 5.3.4 contains of bevy of minor features that improve NCO in many different areas. These range from reduced monotonicity WARNINGs from ncrcat, to an easy new method for all operators to remove global attributes, to bulletproofing ncclimo to work as intended with instantaneous input, to new urban landunit diagnostics in ncks.

Version 5.3.3 adds IEEE floating-point exception testing to ncks. All operators include corner-case quantization fixes for strange numbers (-0.0, NaN) that are also now in the netCDF-C Library. ncclimo now only tries to create regional timeseries statistics on variables that are single-level horizontal lat/lon/ncol fields. ncremap supports interpolation of pure-pressure to hybrid sigma-pressure coordinates with distinct source and destination surface pressure fields. And ncrename adds some words of caution. Skip this release if these changes do not interest you.

Did you realize that the first public release of ncks was May 2, 1995?
https://www.unidata.ucar.edu/mailing_lists/archives/netcdfgroup/1995/msg00069.html
Happy 30th birthday ncks!!!

Version 5.3.2 mainly adds features and fixes to ncremap and quantization. Support for vertical interpolation of ECMWF IFS, and CAMS-format hybrid sigma-pressure vertical coordinate datasets has been improved. And the output is more CF-compliant. All arithmetic operators are once again able to use NCO quantization algorithms on variables in non-root groups. Skip this release if these changes do not interest you.

Version 5.3.1 adds features and fixes to ncremap and ncclimo. The new autoconversion feature allows these scripts to automagically convert netCDF4 string variables to netCDF3 character arrays. The improved treatment of fixed time dimensions allows ncclimo to work with raw MERRA2 files. Together these improvements make possible regridding and vertical interpolation of the new formatting of Copernicus Data Store (CDS) files used for, e.g., ERA5. Skip this release if these changes do not interest you.

Version 5.3.0 significantly improves the unpacking of ELM/CLM/CTSM history and restart datasets, and seems complete in this regard. ncrcat has more friendly behavior when appending, and ncclimo now outputs more metrics (such as valid area per gridcell) when in regional statistics mode. This release many be skipped if these changes do not interest you.