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Timeseries Reshaping mode, aka Splitting
ncclimo will reshape input files that are a series of snapshots of all model variables into outputs that are continuous timeseries of each individual variable taken from all input files. Timeseries to be reshaped (split) often come with hard-to-predict names, e.g., because the number of days or months in a file, or timesteps per day or month may all vary. Thus ncclimo in splitter mode requires the user to supply the input filenames. ncclimo will not construct input filenames itself in splitter mode (unlike monthly or annual climo generation mode). ncclimo will, as of version 4.6.4, automatically switch to timeseries reshaping mode if it receives a list of files through a pipe to stdin, or, alternatively, placed as positional arguments (after the last command-line option), or if neither of these is done and no caseid is specified, in which case it assumes all *.nc files in drc_in constitute the input file list. These examples invoke reshaping mode in the four possible ways (choose your poison):
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The output is a collection of per-variable timeseries such as FSNT_YYYYMM_YYYYMM.nc, AODVIS_YYYYMM_YYYYMM.nc, etc. The output is split into segments each containing no more than ypf_max (default 50) years-per-file, e.g., FSNT_000101_005012.nc, FSNT_005101_009912.nc, FSNT_010001_014912.nc, etc. Change the maximum number of years-per-output-file with the --ypf_max=ypf_max option. One caveat worth noting is that, for technical reasons, non-interactive batch queues cannot unambiguously distinguish filelists provided via stdin from batch queue information provided via stdin. To address this issue, ncclimo supports the --stdin switch to cause the filelist to be read from stdin. This switch is only necessary when running ncclimo in non-interactive batch mode. The switch is permitted though redundant when running ncclimo interactively (i.e., from a terminal shell). The remainder of the ncclimo documentation refers to climatology-generation mode, not to splitter mode.
ncclimo can (as of NCO 4.9.4) reshape timeseries with temporal resolution shorter than one-month, aka, high-frequency timeseries. For E3SM, this typically means timeseries with daily or finer (e.g., hourly) resolution, such as is often output in EAM/ELM h1-h4 datasets. EAM/ELM output these datasets with a fixed number of records (i.e., timesteps) per file. For example, fifteen daily timesteps or 24 hourly timesteps per file. A primary difficulty in processing such datasets is that their boundaries often do not coincide with the desired analysis interval, which might start and end on even boundaries of a month or year. Aligning timeseries to even month or year boundaries requires extra processing logic which users must invoke by setting the climatology mode option to high frequency splitting (hfs), i.e., --clm_md=hfs.
Climatology generation mode (produce monthly, seasonal, and annual climatologies from monthly-mean input data)
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