historical Experiment Setup and Forcings Guidance

Simulation of the climate of the recent past (typically meaning 1850 to present-day) with prescribed carbon dioxide concentrations (for prescribed carbon dioxide emissions, see esm-hist).

Experiment set up

The historical simulation uses a specific set of forcings (see forcings). These should be applied as transient (i.e. time-changing) forcings over the length of the simulation.

The simulation output should start on 1850-01-01 and end on 2021-12-31. Only one ensemble member is required.

Parent experiment

historical branches from the piControl simulation (part of CMIP).

Branch from piControl at a time of your choosing.

Forcings

Versions to use

The forcings relevant for this simulation are listed below. For each forcing, we provide the version(s), in the form of "source ID(s)", which should be used when running this simulation.

{
    "anthropogenic-emissions": ["CEDS-CMIP-2025-04-18", "CEDS-CMIP-2025-04-18-supplemental"],
    "biomass-burning-emissions": ["DRES-CMIP-BB4CMIP7-2-0"],
    "land-use": ["UofMD-landState-3-1-1"],
    "greenhouse-gas-concentrations": ["CR-CMIP-1-0-0"],
    "stratospheric-aerosol-forcing ": ["UOEXETER-CMIP-2-2-1"],
    "ozone": ["FZJ-CMIP-ozone-2-0"],
    "nitrogen-deposition": ["FZJ-CMIP-nitrogen-1-2"],
    "solar": ["SOLARIS-HEPPA-CMIP-4-6"],
    "aerosol-optical-properties": null,
    "population-density": ["PIK-CMIP-1-0-1"]
}

Notes

The following pages give further information on each forcing:

Beyond the information on these pages, please also note the following:

The ozone forcing should come from files with the source ID FZJ-CMIP-ozone-2-0. FZJ-CMIP-ozone-2-0 was released quite late, so if you have simulations based on FZJ-CMIP-ozone-1-2, these would also be of interest to the Forcings Task Team so please publish them (discussion of how to set the value for the forcing 'f' identifier in such files is ongoing).

The aerosol optical properties based on the MACv2-SP parameterisation are not distrubuted via the ESGF.

Please see their specific guidance section for data access information.

Getting the data

The data is available on ESGF and searchable via metagrid, although this method of finding and downloading the data can involve a lot of clicking.

If you install esgpull, you can download all the data associated with the source IDs above with the script shown below. Note that this will download all the data associated with these source IDs, which is likely to be much more data than you actually need to run your model.

#!/bin/bash

EXPERIMENT_NAME="historical"

esgpull add --track --tag ${EXPERIMENT_NAME} source_id:CEDS-CMIP-2025-04-18,CEDS-CMIP-2025-04-18-supplemental,DRES-CMIP-BB4CMIP7-2-0,UofMD-landState-3-1-1,CR-CMIP-1-0-0,UOEXETER-CMIP-2-2-1,FZJ-CMIP-ozone-2-0,FZJ-CMIP-nitrogen-1-2,SOLARIS-HEPPA-CMIP-4-6,PIK-CMIP-1-0-1
esgpull update --tag ${EXPERIMENT_NAME} --yes
esgpull download --tag ${EXPERIMENT_NAME}