Overview: Climate Model Intercomparison Project (CMIP)

The CMIP is a standard experimental framework for studying the output of coupled atmosphere-ocean general circulation models. This facilitates assessment of the strengthsand weaknesses of climate models which can enhance and focus the development of future models. For example, if the models indicate a wide range of values either regionally or globally, then scientists may be able to determine the cause(s) of this uncertainty.

History of the CMIPs

CMIP5 (formally: Coupled Model Intercomparison Project Phase 5) was one of the most extensive of the CMIPs. It is defined by experiment suites divided into three categories: (I) Decadal Hindcasts and Predictions simulations; (II) "long-term" simulations; and (III) "atmosphere-only" (prescribed SST) simulations for especially computationally-demanding models. The objectives are to:

  • evaluate how realistic the models are in simulating the recent past,
  • provide projections of future climate change on two time scales, near term (out to about 2035) and long term (out to 2100 and beyond), and
  • understand some of the factors responsible for differences in model projections, including quantifying some key feedbacks such as those involving clouds and the carbon cycle.

There are many CMIP5 related publications published online.

CMIP5 Data Archives

Publicly available data archives containing CMIP5 model runs are available.  To facilitate use, CMIP5 uses a common naming system for files,directories, metadata and URLs.  These are described in detail in the CMIP5 Data Reference Syntax (DRS) and Controlled Vocabulary.

... to be continued