The CMIP Panel and WGCM Infrastructure Panel (WIP) continue to discuss and evolve the CMIP delivery timeline in close coordination with the CMIP Task Teams and through regular engagement with the wider community. For the DECK and the subset of CMIP experiments aimed at aligning with the IPCC, the CMIP Fast Track, there can be no clear definition until the new IPCC leadership is in place and their timeline is confirmed. This is expected to be late 2023/early 2024. However, the CMIP Panel are actively engaging and discussing with the new IPCC Bureau. Community MIPs do not need to align with that timeline, although they may choose to do so.
We do want to be as prepared as possible for when the IPCC timeline emerges and are therefore in the process of determining community readiness. Current estimates suggest:
- Historical forcings: Update expected, with data extending until December 2021 available by mid-2024 and revised in 2026 (CMIP Forcings timeline – current status).
- Scenario forcings: The ScenarioMIP working timeline currently suggests scenario availability in late 2025/early 2026 (link to ScenarioMIP pages)
- Data request: Initial production versions expected by mid-2025, with regular updates thereafter.
- Modelling centres: Initial consultation on when new models and associated infrastructure will be ready to start simulations has suggested 2024-2026 for the majority of centres.
- ESGF nodes: The ESGF is required to collate and serve the CMIP data. Ongoing discussions led by the WIP and ESGF community are determining capacity and resource requirements and respective timeline.
- Future CMIP description paper: Intention for submission in 2024.
The DECK
- Running the DECK will remain the CMIP “entry card” for centennial scale contribution.
- However, the CMIP Panel are considering potential additions to, or versions of, the DECK both in the short and longer term.
The CMIP Fast Track
- Is intended to be a streamlined set of experiments and will not include whole MIPs but rather a limited selection of experiments from across a number of MIPs.
- Will be aimed at delivering to IPCC and ideally across WGI, II and III (to avoid the problem seen with WGI utilising CMIP6 and WGII using CMIP5 results as seen in the AR6 report) and are therefore either highly policy relevant or address process understanding important to the IPCC context.
- Is not intended to include experiments from across all the MIPs.
- Fast Track experiments will be required to operate under strict timelines, and with associated demands, to meet what will likely be an ambitious IPCC timeline.
- Is not a prioritisation of experiments on any basis apart from timeline.
- The SED TT will be providing recommendations to the Panel on the selection of experiments for the fast track.
The Community MIPs
- 26 MIPs have registered and can be found on the CMIP website.
- The process and level of support for Community MIPs is being discussed by the CMIP Panel.
- The Panel wants to encourage MIPs to not re-run CMIP6 experiments with new models, and to collaborate across MIPs to identify and reduce any potential duplication, and with consideration of their carbon footprint.
- If MIPs have information/news they would like to share with CMIP community, then email
An in-person meeting of the core Panel is taking place in late September in New York to push forward the experimental design of the next phase and discuss the vision for the future of CMIP.
We continue to welcome all feedback from across the community. To stay up to date with the latest developments, please bookmark this page and join our mailing lists here to hear about the latest news and events.
