For the first time in the history of the IPCC, the data on which figures in the report are based are archived and thus become reusable. For each figure, the report's Supplementary Materials document not only the data themselves but also their creation process - from the underlying source data to the processing scripts applied to the final data displayed. The used model and observational data are cited, such as data from climate model simulations conducted as part of the Coupled Model Intercomparison Project Phase 6 (CMIP6). The data shown in figures were published along with the Summary for Policymakers (SPM) and distributed to the press.

The new enhanced data documentation for the latest report complies with the FAIR (Findable, Accessible, Interoperable, Reusable) Guidelines, which were jointly developed and implemented by the Technical Support Unit (TSU) of Working Group I (WGI) and the Data Distribution Centre (DDC) of the IPCC. The FAIR Guidelines enhance the transparency and traceability of the Assessment Report significantly, and figures can be reproduced using the provided figure documentation (Stockhause et al., 2019).

As a DDC Partner, DKRZ has contributed conceptually as well as practically to the implementation of the data guidelines. DKRZ has traditionally operated the Reference Data Archive for the global climate model data throughout the CMIP phases underlying the IPCC Assessment Reports. This task has been expanded for AR6 . DKRZ additionally:

  • contributed to the development and implementation of the FAIR Guidelines,
  • advised the IPCC on data management issues,
  • provided the CMIP6 data citations for the Assessment Report, and
  • supported the IPCC authors by Virtual Workspaces.

Through these Virtual Workspaces, the authors had access to the DKRZ data pool as well as to the Mistral supercomputer with the common software packages installed there, such as the Earth System Model Evaluation Tool (ESMValTool). The ESMValTool was used in several chapters of the report to produce the figures.

After publication of the AR6, the DDC Partner DKRZ is responsible for transferring the CMIP6 model simulation data to the AR6 Reference Data Archive and for integrating references to these data into the digital version of the report. In addition, a joint DDC data catalog for improved data discovery is being established, to which the DDC at DKRZ will contribute the data of the Reference Data Archive.

Not only for DKRZ, but also for the authors, the implementation of the FAIR data Guidelines entailed additional tasks; however, this is crucial for a comprehensible and reproducible presentation of the results. The comprehensive documentation and provision of the data and scripts for all figures will greatly support the authors in the preparation of the next climate Assessment Report.

Contact at DKRZ: Dr. Martina Stockhause (c3RvY2toYXVzZUBka3J6LmRl)

Further information:
6. Assessment Report of the IPCC - Part 1: https://www.ipcc.ch/report/ar6/wg1
Practice Paper: Stockhause, M., Juckes, M., Chen, R., Moufouma Okia, W., Pirani, A., Waterfield, T., Xing, X. and Edmunds, R., 2019. Data Distribution Centre Support for the IPCC Sixth Assessment. Data Science Journal, 18(1), p.20. DOI: http://doi.org/10.5334/dsj-2019-020
Reference Data Archive for global climate simulation data of the CMIP Phases: http://www.ipcc-data.org/sim/gcm_monthly/ und http://ipcc.wdc-climate.de
DKRZ Data Pool: https://doc.dkrz.de/doc/cmip-data-pool/
Earth System Model Evaluation Tool (ESMValTool): https://www.esmvaltool.org/