Overview CMIP6 Experimental Design and Organization

The overview paper on the CMIP6 experimental design and organization has now been published in GMD (Eyring et al., 2016). This CMIP6 overview paper presents the background and rationale for the new structure of CMIP, provides a detailed description of the CMIP Diagnostic, Evaluation and Characterization of Klima (DECK) experiments and CMIP6 historical simulations, and includes a brief introduction to the 21 CMIP6-Endorsed MIPs.

A brief summary can be found in the following overview presentation (CMIP6FinalDesign_GMD_170726.pdf) and below. After a long and wide community consultation, a new and more federated structure has been put in place. It consists of three major elements:

  1. a handful of common experiments, the DECK (Diagnostic, Evaluation and Characterization of Klima) and CMIP historical simulations (1850 – near-present) that will maintain continuity and help document basic characteristics of models across different phases of CMIP,
  2. common standards, coordination, infrastructure and documentation that will facilitate the distribution of model outputs and the characterization of the model ensemble, and
  3. an ensemble of CMIP-Endorsed Model Intercomparison Projects (MIPs) that will be specific to a particular phase of CMIP (now CMIP6) and that will build on the DECK and CMIP historical simulations to address a large range of specific questions and fill the scientific gaps of the previous CMIP phases.

References:

CMIP6 Terms of Use

To enable modeling groups and others who support CMIP6 to demonstrate its impact (and secure ongoing funding), you are required to cite and acknowledge those who have made CMIP6 possible. You also must abide by any licensing restrictions. Please follow the CMIP6 Terms of Use (see here).

CMIP6 Special Issue

A CMIP6 Special Issue is published in GMD (see here). This special issue describes the new design and organization of CMIP and the suite of experiments of its next phase (i.e., CMIP6) in a series of invited contributions. The description of the experiments and forcing data sets define CMIP6 in detail. The papers provide the required information to produce a consistent set of climate model simulations that can be scientifically exploited to address the three broad scientific questions of CMIP6: (1) How does the Earth system respond to forcing?, (2) What are the origins and consequences of systematic model biases?, and (3) How can we assess future climate changes given climate variability, predictability and uncertainties in scenarios? The special issue will include an overview paper on the CMIP6 design and organization, contributions from CMIP6-endorsed MIPs and descriptions of the forcing data sets. 

CMIP6 Data Request

The CMIP6 Data Request is coordinated by the WGCM Infrastructure Panel

Technical Requirements for CMIP6 Participation

A Guide to the technical requirements for CMIP6 Participation is available at https://pcmdi.llnl.gov/CMIP6/Guide/.

This guide is sub-divided into three parts distinguished by the groups served:

  • Modelers carrying out CMIP6 simulations, Data managers responsible for data node operations, and Data users analyzing and making use of CMIP6 model output.

Model groups that participate in CMIP6 will have to register by following the steps outlined under “1. Requirements and expectations” at https://pcmdi.llnl.gov/CMIP6/Guide/modelers.html, including a registration of the scientific contacts with CMIP Panel Chair, This email address is being protected from spambots. You need JavaScript enabled to view it..

CMIP6 Forcing Datasets

The CMIP6 forcing datasets needed for the DECK, historical, and CMIP6-Endorsed MIP experiments are briefly described at http://goo.gl/r8up31. That document also provides links to the forcing data itself and to documentation.

  • The CMIP Panel has released the CMIP6 Forcing Datasets for DECK and Historical Simulations (v1.0) on 20 December 2016. At http://goo.gl/r8up31 and in input4MIPs, this is now version 6.0.0 (20th December 2016) - Initial DECK and historical forcings dataset release.
  •  6.1.0 (17th May 2017) - This version is the updated official CMIP6 forcings dataset collection. It supersedes the original 6.0.0 version released on the 20th December 2016. Two key datasets from the original release have been revised:

Please always check at http://goo.gl/r8up31 for minor updates compared to the official CMIP Panel releases. Not all of the other datasets have been released for use in CMIP6, and that is clearly indicated in the document. All forcing datasets are described in the CMIP6 Special Issue and we encourage the community to participate in the open discussion.

  • Historical SLCF and GHG (CO2 and CH4) Emissions – Contact: Steve Smith (This email address is being protected from spambots. You need JavaScript enabled to view it.)
    • Initial Description: Date 19 February 2015 (for the initial description, click here)
    • Data Description: Date 5 February 2016 (for a short data description, click here. A sample gridded dataset for year 2000 intended for model input set-up, including SO2, NOx, CO, NMVOC, NH3, BC, and OC is available at this link. This package contains sample netCDF files for the year 2000. These data are not final, but can be used to set-up read-in routines, review, and testing ). Modelers who would additionally like a sample year for speciated VOCs should contact Steve Smith. Feedback on these test data is requested by end of February and the final historical emissions for short-lived species for CMIP6 will be released by early March 2016, or as soon as data distribution facilitates are operational.
    • 26 June 2016: Data are available at https://esgf-node.llnl.gov/projects/input4mips
    • Historical SLCF emissions are available at https://esgf-node.llnl.gov/projects/input4mips. Gridded Historical Anthropogenic GHG Emissions to become available early next year. Please see google doc spreadsheet above for updates.
  • Global Gridded Land-use Forcing Datasets – Contact: George Hurtt (This email address is being protected from spambots. You need JavaScript enabled to view it.)
    • Initial Description: Date 31 January 2015 (for the initial description, click here)
    • 12 November 2015: DRAFT land-Use Harmonization dataset (LUH2-v0.3) is available, and intended for model I/0 and testing (https://cmip.ucar.edu/lumip)
    • 29 March 2016: A beta release of the historical land-use forcing dataset (LUH2 v1.0h_beta) is now available, covering the period 850-2015. LUH2 v1.0h_beta is a prototype, intended for model testing and development only. The emphasis in this version is on the format of the intended data products; data values are close to final but will likely change in the finished product, and are not intended nor suitable for publication quality work. A README file describing the dataset, and how to download it, is available here. This information is also available from the LUMIP website (https://cmip.ucar.edu/lumip). Please test this dataset and send any feedback you might have to George Hurtt (email: This email address is being protected from spambots. You need JavaScript enabled to view it.), L. Chini (This email address is being protected from spambots. You need JavaScript enabled to view it.), and S. Frolking (This email address is being protected from spambots. You need JavaScript enabled to view it.). The final release of this dataset is planned for end of March.
    • Future Global Gridded Land-use Forcing Datasets for CMIP6 will be made available by ~ end of July 2016.
    • 26 June 2016: Datasets are available from http://luh.umd.edu. Dataset format is being reconsidered for publication to ESGF.
    • data are available from http://luh.umd.edu and will also be made available on input4MIPs, see http://goo.gl/r8up31 for upates
  • Historical GHG concentrations – Contact: Malte Meinshausen (This email address is being protected from spambots. You need JavaScript enabled to view it.) and Alexander Nauels (This email address is being protected from spambots. You need JavaScript enabled to view it.)
  • Ozone Concentrations and Nitrogen (N)-Deposition – Contact: Michaela Hegglin (This email address is being protected from spambots. You need JavaScript enabled to view it.)
    • Initial Description: Date 19 February 2015 (for the initial description, click here)
    • Please see the following website for updates on the ozone and N-deposition database for CMIP6: http://www.met.reading.ac.uk/ccmi/?page_id=375
    • Pre-historical ozone and N-deposition database (1850) expected by ~ end of January 2016; Historical ozone and N-deposition database (1850-2014) expected by end of April 2016; Future ozone and N-deposition database (2015-2100) expected by ~end of October 2016.
    • 26 June 2016: In accordance with the original agreed timeline for the forcing datasets, the historical forcings for ozone and nitrogen deposition will be made available via the CCMI website at http://www.met.reading.ac.uk/ccmi/?page_id=375 by mid-July.
    • Data are available at https://esgf-node.llnl.gov/projects/input4mips
  • Aerosol Optical Properties and Relative Change in Cloud Droplet Number Concentration – Contact:, Bjorn Stevens (This email address is being protected from spambots. You need JavaScript enabled to view it.)
  • Stratospheric Aerosol Data Set – Contacts: Beiping Luo (This email address is being protected from spambots. You need JavaScript enabled to view it.), Thomas Peter (This email address is being protected from spambots. You need JavaScript enabled to view it.) and Larry Thomason (This email address is being protected from spambots. You need JavaScript enabled to view it.)
    • Initial Description: Date 31 January 2015 (for the initial description, click here)
    • 3 March 2016: A beta release of stratospheric aerosol data for use in CMIP6 models intended for model testing and development only is now available at ftp://iacftp.ethz.ch/pub_read/luo/CMIP6/. Corresponding plots, a data description and a read routine (3l_read.f) is also available in that folder. Please provide feedback to Beiping Luo by 20 March 2016. The final release of this dataset is planned for end of March.
    • 26 June 2016: Datasets are available from ftp://iacftp.ethz.ch/pub_read/luo/CMIP6. Important notes: (1) If you have downloaded this forcing dataset before 16 June, please download it again since there are major revisions on SAD and the data file CMIP_1850_2014_sad_average_V2.nc should be used, and a small bug has been corrected in the radiative properties. (2) As noted in my email dated 21st Apr 2016, modeling centers should get in contact directly with Beiping so correct bandwidth data can be provided for each model. Please do so if your model is not yet listed at the website above.
    • data are available from ftp://iacftp.ethz.ch/pub_read/luo/CMIP6 and will also be made available on input4MIPs, see http://goo.gl/r8up31 for upates
  • AMIP Sea Surface Temperature and Sea Ice Datasets – Contact: PCMDI (This email address is being protected from spambots. You need JavaScript enabled to view it.)
  • Future Emissions – Contact: Detlef van Vuuren (This email address is being protected from spambots. You need JavaScript enabled to view it.) and Brian O’Neill (This email address is being protected from spambots. You need JavaScript enabled to view it.)
    • For information on the future scenarios that will be run by global climate models within CMIP6, see the ScenarioMIP website at http://cmip.ucar.edu/scenario-mip. More information on the Shared Socioeconomic Pathways (SSPs) can be found at the SSP Database at https://tntcat.iiasa.ac.at/SspDb/dsd?Action=htmlpage&page=about.
    • All forcing data (land use, emissions, extensions) required for the future SSP-RCPs selected in ScenarioMIP will be made publicly accessible at the SSP database and will be made available by September 2017.

 

CMIP6 Model Evaluation System

Contacts: This email address is being protected from spambots. You need JavaScript enabled to view it. and This email address is being protected from spambots. You need JavaScript enabled to view it. 

Over the last decades significant progress has been made in model evaluation. The CMIP community has now reached a critical juncture at which many baseline aspects of model evaluation need to be performed much more efficiently to enable a systematic and rapid performance assessment of the large number of models participating in CMIP. Such an evaluation system will be implemented for CMIP6. Our initial goal is that two capabilities will be used to produce a broad characterization of CMIP DECK and historical simulations as soon as new CMIP6 model experiments are published to the Earth System Grid Federation (ESGF):

(a) the Earth System Model Evaluation Tool (ESMValTool, Eyring et al., 2016a) is a community-developed diagnostic and performance metrics tool for the evaluation of Earth system models with observations. It includes other well-established model evaluation packages such as the NCAR Climate Variability Diagnostics Package (CVDP, Phillips et al., 2014). The collection of standard namelists for example allows to reproduce the figures from the climate model evaluation chapter of IPCC AR5 (Chapter 9) and parts of the projection chapter (Chapter 12). The ESMValTool is available as open source software on GitHub (https://github.com/ESMValGroup/ESMValTool).

(b) the PCMDI Metrics Package (PMP, Gleckler et al., 2016) emphasizes a diverse suite of summary statistics to objectively gauge the level of agreement between model simulations and observations across a broad range of space and time scales. It is built on the Python based Ultrascale Visualization Climate Data Analysis Tools (UV-CDAT), a powerful software tool kit that provides cutting-edge data management, diagnostic and visualization capabilities. The PMP is available as open source software on GitHub (https://github.com/PCMDI/pcmdi_metrics).

Since these tools are freely available on GitHub, modelling groups participating in CMIP can additionally make use of these packages. They could choose, for example, to utilize the tools during the model development process in order to identify relative strengths and weaknesses of new model versions also in the context of the performance of other models or they could run the tools locally before publishing the model output to the ESGF. Mechanisms are in place to enable contributions from the broader community. Both tools are designed to readily work across ESGF nodes with the intent of ultimately expediting routine analysis by alleviating the needs for data transfer. We expect the benefits of this activity to become increasingly apparent during the research phase of CMIP6. We encourage the community to consider contributing additional diagnostics and metrics to these CMIP6 evaluation tools. More details on this approach can be found in Eyring et al. (2016b).

References:

 

Applications for CMIP6 Endorsed MIPs

See https://www.wcrp-climate.org/modelling-wgcm-mip-catalogue/modelling-wgcm-cmip6-endorsed-mips

CMIP5 survey

  • CMIP5 Survey - sent out to representatives of the climate community end of June 2013
  • Synthesis of CMIP5 Survey (August 2013) (Presentation by Veronika Eyring and Ron Stouffer at the Workshop ‘Next Generation Climate Change Experiments Needed to Advance Knowledge and for Assessment of CMIP6’, 5 August 2013, Aspen, CO, USA
  • Synthesis of CMIP5 Survey (October 2013) (Presentation by Veronika Eyring and Ron Stouffer at the WGCM 17th Session, 1-3 October 2013, Victoria, Canada)

Previous iterations on the CMIP6 Design

The CMIP6 design and organization was finalized at the WGCM 18th Session that was held 8-10 October 2014 in Grainau/Garmisch-Partenkirchen (Germany).

A brief summary can be found in the following overview presentation (CMIP6FinalDesign_WGCMMeeting_150116_Sent.pdf) and below. The final CMIP6 Design, possibly with small modifications to the here presented figures and wording, will be published in a GMD Special Issue together with a description of the CMIP6-Endorsed MIPs and the forcing datasets. This Special Issue will open 30 April 2015.

The DECK which will serve as an entry card for CMIP will consist of the following four simulations: (a) AMIP simulation (~1979-2014); (b) Pre-industrial control simulation; (c) 1%/yr CO2 increase, and (d) Abrupt 4xCO2 run. In addition, the CMIP6 Historical Simulation has been added which will serve as the entry card for CMIP6 and as a benchmark for CMIP6-Endorsed MIPs . The historical simulation (1850-2014) will use the specific forcings consistent with CMIP6 which will be finalized on the timescales laid out in slide 10. The CMIP6 Historical Simulation has been introduced in addition to the DECK to better separate CMIP from a specific Phase of CMIP (see slide 4 for illustration and slide 5 for the main criteria for DECK and Historical Phase X). Both DECK and the CMIP6 Historical Simulation should be run for each model configuration used in the subsequent CMIP6-Endorsed MIPs. Future climate change scenarios will be run as part of ScenarioMIP with a Tier 1 that includes three different scenarios, spanning different possible futures.

The criteria for MIP endorsement have been streamlined and agreed at the WGCM 18th session. They now comprise a single set covering MIPs and their experiments. A timeline towards MIP endorsement and beyond has been agreed. Input to the data request will be coordinated by the WGCM Infrastructure Panel.