Download software

Software packages

CISL and NCAR have developed and support a number of freely available software packages for data assimilation, analysis, visualization and high-performance computation.

See the DART, GeoCAT, and VAPOR sites described below for more information and to download software, and visit the Advanced Research Computing portal for details about other software available on NCAR's HPC systems.

Data Assimilation Research Testbed


DART overview text on a blue background.

The Data Assimilation Research Testbed (DART) is a community software facility, a collection of programs, scripts, and tools that supports data assimilation (DA) for many different kinds of geophysical models and many types of observations. It allows modelers and experimenters to use state-of-the-art DA algorithms with a minimum investment in software and algorithm development and without having to become experts in DA.

DART supports ensemble methods of DA and provides an alternative to more resource-intensive variational methods. Because DART is easy to use, it also allows for teaching DA to students in a hands-on laboratory setting. Finally, DART provides a framework for the DA expert to build new algorithms and easily test them with both simple models and UCAR and other community models.

See Dart software download for more information.

Geoscience Community Analysis Toolkit


GeoCAT software logo

The Geoscience Community Analysis Toolkit (GeoCAT) is a collection of tools for scientific visualization, file input/output and data analysis.

The collection includes the GeoCAT computational library (GeoCAT-Comp) and the PyNGL and PyNIO Python packages.



VAPOR software logo

Visualization and Analysis Platform for Ocean, Atmosphere, and Solar Researchers (VAPOR) – provides an interactive 3D visualization environment that can also produce animations and still frame images.

NCAR Classic Libraries for Geophysics


Rendering of a scalar harmonic produced by a SPHEREPACK subroutine.

Rendering of a scalar harmonic produced by a SPHEREPACK subroutine.

Several mathematical libraries developed in the years 1970-1990 remain popular in the geophysics community. These libraries are:

  • FFTPACK: A library of fast Fourier transforms
  • FISHPACK: Fortran subprograms for solving separable elliptic partial differential equations (PDEs)
  • FISHPACK 90: FISHPACK subprograms with a Fortran 90 interface
  • MUDPACK: Multigrid Fortran subprograms for solving separable and non-separable elliptic PDEs
  • SPHEREPACK: A Fortran library for modeling geophysical processes

The libraries are available for downloading here on GitHub: NCAR Classic Libraries for Geophysics.