What is CIME?

CIME, pronounced “SEAM”, contains the support scripts (configure, build, run, test), data models, essential utility libraries, a “main” and other tools that are needed to build a single-executable coupled Earth System Model. CIME is available in a stand-alone package that can be compiled and tested without active prognostic components but is typically included in the source of a climate model. CIME does not contain: any active components, any intra-component coupling capability (such as atmosphere physics-dynamics coupling).

Overview

CIME is comprised of:

  1. A Case Control System to support configuration, compilation, execution, system testing and unit testing of a earth system model:

    1. Scripts to enable simple generation of model executables and associated input files for different scientific cases, component resolutions and combinations of full, data and stub components with a handful of commands.

    2. Testing utilities to run defined system tests and report results for different configurations of the coupled system.

  2. A default coupled model architecture:

    1. A programmer interface and libraries to implement a hub-and-spoke inter-component coupling architecture.

    2. An implementation of a “hub” that needs 7 components (atm, ocn, lnd, sea-ice, land-ice, river, wave). a.k.a. “the driver”.

    3. The ability to allow active and data components to be mixed in any combination as long as each component implements the coupling programmer interface.

  3. Non-active Data and Stub components:

    1. “Data-only” versions of 6 of the 7 components that can replace active components at build-time.

    2. “Stub” versions of all 7 components for building a complete system.

  4. Source code for external libraries useful in scientific applications in general and climate models in particular.

    1. Parallel I/O library.

    2. The Model Coupling Toolkit.

    3. Timing library.

  5. Additional stand-alone tools:

    1. Parallel regridding weight generation program

    2. Scripts to automate off-line load-balancing.

    3. Scripts to conduct ensemble-based statistical consistency tests.

    4. Netcdf file comparison program (for bit-for-bit).

Development

CIME is developed in an open-source, public repository hosted under the Earth System Model Computational Infrastructure (ESMCI) organization on Github at http://github.com/ESMCI/cime.