Last Verified: 2023-12-19


NCAR Graphics is a Fortran and C based software package for scientific visualization. It consists of routines for drawing contours, maps, vectors, streamlines, weather maps, surfaces, histograms, X/Y plots, annotations, and more. It is provided by the National Center for Atmospheric Research (NCAR).

NCL is a programming language designed specifically for the access, analysis, and visualization of data. NCL can be run in interactive mode, where each line is interpreted as it is entered at your workstation, or it can be run in batch mode as an interpreter of complete scripts. NCL is available for free in binary format for several UNIX systems.

View a gallery of visualizations created with NCL to see what can be done with NCL.

NCL is a product from the National Center for Atmospheric Research.


Machines and Versions

See LC visualization software page.


Multiple versions are accessible via modules. Type module avail ncar to see the available options. Note that NCAR modules are compiler specific; The available modules will vary based on your active compiler module (e.g., gcc, intel). You can type module list to see your currently loaded modules.

You can specify a particular version in the module command, e.g., module load ncl_ncarg/6.3.0

The actual installation directories are in /usr/tce/packages/ncar


Load the desired module to add the NCAR binaries to your PATH. No additional settings are required to use NCAR or NCL. Note that NCL is only included in the packages/modules with "ncl" in their names.


For information on using NCL, refer to the NCL Home Page.

Use the ng4ex command to view example NCL programs. Refer to the ng4ex man page for more information.


An NCL email list is available.

Additional documentation is available from the NCL Documentation page.

NCL Application Examples are available via the NCL Applications Examples page.

Help is available from the LC Hotline:, (925) 422-4531.

The following man pages are available as part of the modules:

  • man ncargintro
    NCAR Graphics overview
  • man ncargf77
    Command for compiling Fortran code that uses the NCAR Graphics low-level utilities
  • man ncargcc
    Command for compiling C code that uses the NCAR Graphics low-level utilities
  • man ncargex
    NCAR Graphics Fortran and C Low-Level Utility Examples
  • man ctrans
    A Computer Graphics Metafile (CGM) translator
  • man ncgm2cgm
    Filter NCAR CGM to/from vanilla CGM


To download NCL to your local workstation, refer to the NCL Download page.