Skip to contents

Display vertical levels in depth-resolved climate data

Source: R/htr_show_levels.R
htr_show_levels.Rd

This function examines 3D ocean climate model data and displays the vertical levels (depths or pressure levels) available in each file using CDO (Climate Data Operators). This is useful for understanding the vertical structure of ocean models before performing depth-related operations.

Usage

htr_show_levels(indir)

Arguments

indir

Character string. Directory containing 3D NetCDF files with vertical levels (typically ocean model outputs with depth or pressure coordinates).

Value

Character vector containing the vertical level information for each file. Each element corresponds to one input file and contains the level values as returned by CDO showlevel.

Details

Ocean climate models use various vertical coordinate systems (depth in meters, pressure levels, sigma coordinates, etc.). This function uses the CDO showlevel operator to display the vertical levels present in each file, helping users understand the vertical resolution and coordinate system.

The function:

  1. Processes all NetCDF files in the input directory

  2. For each file, executes cdo showlevel filename to extract level information

  3. Prints the filename and returns the level information

  4. Collects all level information into a character vector

This information is essential for:

  • Understanding the vertical structure of ocean models

  • Planning depth integration operations with htr_integrate_levels()

  • Selecting appropriate level ranges for analysis

Note

  • Requires CDO (Climate Data Operators) to be installed and accessible from the system PATH

  • Input files must be 3D data with vertical coordinate dimensions

  • Prints filenames to console for progress tracking

  • Level values and units depend on the model's vertical coordinate system

  • Does not use parallel processing (processes files sequentially)

References

CDO User Guide: https://code.mpimet.mpg.de/projects/cdo/embedded/cdo.pdf CDO showlevel operator: https://code.mpimet.mpg.de/projects/cdo/embedded/cdo.pdf#page=144

Examples

if (FALSE) { # \dontrun{
# Display levels in ocean model data
levels_info <- htr_show_levels(
  indir = file.path(base_dir, "data", "proc", "sliced", "omip", "thetao")
)

# View the level information
print(levels_info)
} # }