Climate Forcings Task Team

Co-leads: Paul Durack PCMDI/LLNL and Vaishali Naik, NOAA

This task team will focus on how the CMIP required forcing agents will need to broaden for CMIP7. Climate forcings play a key role in the definition of exogenous drivers of ongoing climate change. As such, they are an integral part of the definition of historical, future scenario and idealised simulations.

On this page:

Challenge
Aim & Objectives
Core Goals
Forcing Datasets Update Timeline
Publications
Members
Activities

Challenge

The CMIP6 forcings include:

emissions (CO2, aerosol, and ozone precursors from anthropogenic and biomass burning sources)
concentrations (CO2 and other long-lived greenhouse gases, aerosols, ozone)
volcanoes (emissions and concentrations)
land-use/land cover change, ocean and atmosphere boundary conditions for atmosphere and ocean experiments respectively, in addition to numerous other climate forcing agents.

Due to the expanding complexities of Earth System Models to represent more processes explicitly, it is anticipated that the required forcing agents will need to broaden for CMIP7. As model configurations continue to target higher and higher spatial resolution, additional expansion of temporal and geographical resolutions may be required.

Aim & Objectives

The aim of this TT is to identify and implement the next generation forcings for current and future generations of Earth System models.

Objectives:

Evaluate the CMIP6 forcing collection and identify issues, coverage gaps or omitted fields (e.g., natural, not anthropogenic, CH4 emissions).
Identify next generation forcings for current and future generations of Earth System models.
Work with teams to deliver them.
Coordinate with modelling groups to perform evaluation and generate simulations using the newly generated/updated forcing datasets

The TT will also be coordinating closely with the various Model Intercomparison Projects (MIPs) to ensure consistency between the experimental design and the required forcings. The WCRP Lighthouse Activity Explaining and Predicting Earth System Change (EPESC) and Coordinated Regional Downscaling Experiment (CORDEX) will also be important stakeholders.

Core Goals

Following the first three meetings of the Climate Forcings Task Team, four core goals have been identified. These goals were approved by all Task Team members in April 2023. Select each goal in the view below to see its related sub-goals. The goals can also be viewed in PDF form by following this link.

Forcing datasets update timeline

The Forcings Task Team have compiled a timeline of when each forcing dataset is expected to provide an update to their data. The datasets included are:

Anthropogenic short-lived climate forcings (including CO₂and CH₄)
Open biomass burning emissions
Land use
Greenhouse gas historical concentrations
Stratospheric volcanic SO₂ emissions and aerosol properties
Ozone
Nitrogen deposition
Solar
AMIP boundary forcing
Aerosol optical properties/MACv2-SP

The timeline has been published in the WCRP-CMIP Zenodo Collection. Updates to this timeline are expected to be regular. For the latest version of the timeline, please check the published Zenodo record by following this link (opens in a new tab).

Publications

Forcings drop in session report

A series of regular drop-in sessions was launched in early 2023, facilitated by the CMIP International Project Office (CMIP IPO), to cover key aspects of CMIP7 design and development and promote community feedback to the CMIP governance and Task Teams.

On 7 June 2023, the first two Forcings drop-in sessions were held across two time-slots (05:00 UTC and 16:00 UTC) to support equitable global participation. These sessions were chaired by one of the CMIP Panel co-chairs John Dunne (GFDL/NOAA) or Helene Hewitt (Met Office) and led by the Forcings Task Team co-leads, Paul Durack (PCMDI/LLNL) and Vaishali Naik (GFDL/NOAA) with input from the wider Task Team membership.

In these sessions, participants were introduced to the Task Team’s members and stakeholders together with the core goals they are seeking to address. Further, feedback received in the recent Future CMIP Forcings Community Survey was outlined and how the task team is addressing issues raised here, to deliver to CMIP7 and tackle longer term scientific challenges, before opening the session for an interactive dialogue with participants.This has now been summarised in an event report, which we have published today in the Zenodo WCRP-CMIP Community. Slides from the session can also be found in the Zenodo WCRP-CMIP Community, or can be accessed at this link (opens in a new tab).

Members