Table of Contents

Introduction

What are global climate projections?

Global climate projections are simulations of the climate system performed with general circulation models which represent physical processes in the atmosphere, ocean, cryosphere and land surface. These models cover the entire globe and use information about the external influences on the system. Such simulations have been generated by multiple independent climate research centres in an effort coordinated by the World Climate Research Program (WCRP) and assessed by the Intergovernmental Panel on Climate Change (IPCC). These climate projections underpin the conclusions of the IPCC Assessment Reports that “Continued emission of greenhouse gases will cause further warming and long-lasting changes in all components of the climate system, increasing the likelihood of severe, pervasive and irreversible impacts for people and ecosystems”.

The Climate Model Intercomparison Project (CMIP)

The Climate Model Intercomparison Project (CMIP) was established in 1995 by the World Climate Research Program (WCRP) to provide climate scientists with a database of coupled Global Circulation Model (GCM) simulations.

 The CMIP process involves institutions (such as national meteorological centres or research institutes) from around the world running their climate models with an agreed set of input parameters (forcings). The modelling centres produce a set of standardised output. When combined, these produce a multi-model dataset that is shared internationally between modelling centres and the results compared.

 Analysis of the CMIP data allows for

  • an improved understanding of the climate, including its variability and change,
  • an improved understanding of the societal and environmental implications of climate change in terms of impacts, adaptation and vulnerability,
  • informing the Intergovernmental Panel on Climate Change (IPCC) reports.

Comparison of different climate models allows for

  • determining why similarly forced models produce a range of responses,
  • evaluating how realistic the different models are in simulating the recent past,
  • examining climate predictability.

CMIP6

The sixth phase of the Coupled Model Intercomparison Project (CMIP6) consists of 134 models from 53 modelling centres (Durack, 2020). CMIP6 data publication began in 2019 and the majority of the data publication was completed in 2022. The scientific analyses from CMIP6 will be used extensively in the Intergovernmental Panel on Climate Change (IPCC) 6th Assessment Report (AR6), due for release in 2021/22 (IPCC, 2020).

CMIP6 aims to address 3 main questions:

  • How does the Earth system respond to forcing?
  • What are the origins and consequences of systematic model biases?
  • How can we assess future climate changes given internal climate variability, predictability, and uncertainties in scenarios (Eyring et al, 2016)?

There are some differences between the experimental design and organisation of CMIP6 and its predecessor CMIP5. It was decided that for CMIP6, a new and more federated structure would be used, consisting of the following 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;
  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 (World Climate Research Programme, 2020).

The CMIP6 data archive is distributed through the Earth System Grid Federation (ESGF) though many national centres have either a full or partial copy of the data. A quality-controlled subset of CMIP6 data are made available through the Climate Data Store (CDS) for the users of the Copernicus Climate Change Service (C3S).

Global climate projections in the CDS

The global climate projections in the Climate Data Store (CDS) are a quality-controlled subset of the wider CMIP6 data. These data represent only a small subset of CMIP6 archive. A set of 51 core variables from the CMIP6 archive were identified for the CDS. These variables are provided from 9 of the most popular CMIP6 experiments. These data can be used to assess plausible future changes in the variables provided, under a range of socio-economic pathways.

The CDS subset of CMIP6 data has been through a quality control procedure which ensures a high standard of dependability of the data. Additional data can be found in the main CMIP6 ESGF archive, however these data come with very limited quality assurance and may have metadata errors or omissions.

The present CDS subset of the CMIP6 dataset was first published in March 2021. This means that the data provided in the CDS reflects the status as of the end of 2020/early 2021. A full synchronisation with the evolution of the CMIP6 dataset in the ESGF is not practical, due to the continually evolving nature of the ESGF archive. A major update and synchronisation is planned in early 2025. In practise it means that there might be some data in the CDS which were withdrawn from ESGF,  or that newly published data in ESGF does not appear in the CDS. See more details in the Known issues section below. Please also note that while the IPCC and the C3S Atlas datasets were added later in the CDS (in 2023 and 2024), the datasets (including CMIP6) had an additional, rigorous quality control applied. This means that CDS data used for the C3S Atlas should be the starting point for exploring the available climate projections. See more details at Models used for the gridded monthly climate projection dataset underpinning the IPCC AR6 Interactive Atlas and Gridded data underpinning the Copernicus Interactive Climate Atlas: Description of the datasets and variables.

Experiments

Shared Socioeconomic Pathway (SSP) Experiments

The SSP scenario experiments can be understood in terms of two pathways, a Shared Socioeconomic Pathway (SSP) and a Representative Concentration Pathway (RCP). The two pathways are represented by the three digits that make up the experiment’s name. The first digit represents the SSP storyline for the socio-economic mitigation and adaptation challenges that the experiment represents (Figure 1). The second and third digits represent the RCP climate forcing that the experiment follows. For example, experiment ssp245 follows SSP2, a storyline with intermediate mitigation and adaptation challenges, and RCP4.5 which leads to a radiative forcing of 4.5 Wm-2 by the year 2100.


Figure 1 - The socioeconomic “Challenge Space” to be spanned by the CMIP6 SSP experiments (O’Neil et al. 2014).

Experiments in the CDS

The CDS-CMIP6 subset consists of the CMIP6 experiments detailed in the table below.


Experiment name

Extended Description

historical

The historical experiment is a simulation of the recent past from 1850 to 2014, it is performed with a coupled atmosphere-ocean general circulation model (AOGCM). In the historical simulations the model is forced with changing conditions (consistent with observations) which include atmospheric composition, land use and solar forcing. The initial conditions for the historical simulation are taken from the pre-industrial control simulation (piControl) at a point where the remaining length of the piControl is sufficient to extend beyond the period of the historical simulation to the end of any future "scenario" simulations run by the same model. The historical simulation is used to evaluate model performance against present climate and observed climate change.

SSP5-8.5

SSP5-8.5 is a scenario experiment extending into the near future from 2015 to 2100, it is performed with a coupled atmosphere-ocean general circulation model (AOGCM). The forcing for the CMIP6 SSP experiments is derived from shared socioeconomic pathways (SSPs), a set of emission scenarios driven by different socioeconomic assumptions, paired with representative concentration pathways (RCPs), global forcing pathways which lead to specific end of century radiative forcing targets. SSP5-8.5 is based on SSP5 in which climate change mitigation challenges dominate and RCP8.5, a future pathway with a radiative forcing of 8.5 W/m2 in the year 2100. The ssp585 scenario represents the high end of plausible future forcing pathways.  SSP5-8.5 is comparable to the CMIP5 experiment RCP8.5.

SSP3-7.0

SSP3-7.0 is a scenario experiment extending into the near future from 2015 to 2100, it is performed with a coupled atmosphere-ocean general circulation model (AOGCM). The forcing for the CMIP6 SSP experiments is derived from shared socioeconomic pathways (SSPs), a set of emission scenarios driven by different socioeconomic assumptions, paired with representative concentration pathways (RCPs), global forcing pathways which lead to specific end of century radiative forcing targets. SSP3-7.0 is based on SSP3 in which climate change mitigation and adaptation challenges are high and RCP7.0, a future pathway with a radiative forcing of 7.0 W/m2 in the year 2100. The SSP3-7.0 scenario represents the medium to high end of plausible future forcing pathways. SSP3-7.0 fills a gap in the CMIP5 forcing pathways that is particularly important because it represents a forcing level common to several (unmitigated) SSP baseline pathways.

SSP2-4.5

SSP2-4.5 is a scenario experiment extending into the near future from 2015 to 2100, it is performed with a coupled atmosphere-ocean general circulation model (AOGCM). The forcing for the CMIP6 SSP experiments is derived from shared socioeconomic pathways (SSPs), a set of emission scenarios driven by different socioeconomic assumptions, paired with representative concentration pathways (RCPs), global forcing pathways which lead to specific end of century radiative forcing targets. SSP2-4.5 is based on SSP2 with intermediate climate change mitigation and adaptation challenges and RCP4.5, a future pathway with a radiative forcing of 4.5 W/m2 in the year 2100. The ssp245 scenario represents the medium part of plausible future forcing pathways. SSP2-4.5 is comparable to the CMIP5 experiment RCP4.5.

SSP1-2.6

SSP1-2.6 is a scenario experiment extending into the near future from 2015 to 2100, it is performed with a coupled atmosphere-ocean general circulation model (AOGCM). The forcing for the CMIP6 SSP experiments is derived from shared socioeconomic pathways (SSPs), a set of emission scenarios driven by different socioeconomic assumptions, paired with representative concentration pathways (RCPs), global forcing pathways which lead to specific end of century radiative forcing targets. SSP1-2.6 is based on SSP1 with low climate change mitigation and adaptation challenges and RCP2.6, a future pathway with a radiative forcing of 2.6 W/m2 in the year 2100. The SSP1-2.6 scenario represents the low end of plausible future forcing pathways. SSP1-2.6 depicts a "best case" future from a sustainability perspective.

SSP4-6.0

SSP4-6.0 is a scenario experiment extending into the near future from 2015 to 2100, it is performed with a coupled atmosphere-ocean general circulation model (AOGCM). The forcing for the CMIP6 SSP experiments is derived from shared socioeconomic pathways (SSPs), a set of emission scenarios driven by different socioeconomic assumptions, paired with representative concentration pathways (RCPs), global forcing pathways which lead to specific end of century radiative forcing targets. SSP4-6.0 is based on SSP4 in which climate change adaptation challenges dominate and RCP6.0, a future pathway with a radiative forcing of 6.0 W/m2 in the year 2100. The SSP4-6.0 scenario fills in the range of medium plausible future forcing pathways. SSP4-6.0 defines the low end of the forcing range for unmitigated SSP baseline scenarios.

SSP4-3.4

SSP4-3.4 is a scenario experiment extending into the near future from 2015 to 2100, it is performed with a coupled atmosphere-ocean general circulation model (AOGCM). The forcing for the CMIP6 SSP experiments is derived from shared socioeconomic pathways (SSPs), a set of emission scenarios driven by different socioeconomic assumptions, paired with representative concentration pathways (RCPs), global forcing pathways which lead to specific end of century radiative forcing targets. SSP4-3.4 is based on SSP4 in which climate change adaptation challenges dominate and RCP3.4, a future pathway with a radiative forcing of 3.4 W/m2 in the year 2100. The SSP4-3.4 scenario fills a gap at the low end of the range of plausible future forcing pathways. SSP4-3.4 is of interest to mitigation policy since mitigation costs differ substantially between forcing levels of 4.5 W/m2 and 2.6 W/m2.

SSP5-3.4OS

SSP5-3.4OS is a scenario experiment with simulations beginning in the mid-21st century running from 2040 to 2100, it is performed with a coupled atmosphere-ocean general circulation model (AOGCM). The forcing for the CMIP6 SSP experiments is derived from shared socioeconomic pathways (SSPs), a set of emission scenarios driven by different socioeconomic assumptions, paired with representative concentration pathways (RCPs), global forcing pathways which lead to specific end of century radiative forcing targets. SSP5-3.4OS is based on SSP5 in which climate change mitigation challenges dominate and RCP3.4-over, a future pathway with a peak and decline in forcing towards an eventual radiative forcing of 3.4 W/m2 in the year 2100. The SSP5-3.4OS scenario branches from SSP5-8.5 in the year 2040 whereupon it applies substantially negative net emissions. SSP5-3.4OS explores the climate science and policy implications of a peak and decline in forcing during the 21st century. SSP5-3.4OS fills a gap in existing climate simulations by investigating the implications of a substantial overshoot in radiative forcing relative to a longer-term target.

SSP1-1.9

SSP1-1.9 is a scenario experiment extending into the near future from 2015 to 2100, it is performed with a coupled atmosphere-ocean general circulation model (AOGCM). The forcing for the CMIP6 SSP experiments is derived from shared socioeconomic pathways (SSPs), a set of emission scenarios driven by different socioeconomic assumptions, paired with representative concentration pathways (RCPs), global forcing pathways which lead to specific end of century radiative forcing targets. SSP1-1.9 is based on SSP1 with low climate change mitigation and adaptation challenges and RCP1.9, a future pathway with a radiative forcing of 1.9 W/m2 in the year 2100. The SSP1-1.9 scenario fills a gap at the very low end of the range of plausible future forcing pathways. SSP1-1.9 forcing will be substantially below SSP1-2.6 in 2100. There is policy interest in low-forcing scenarios that would inform a possible goal of limiting global mean warming to 1.5°C above pre-industrial levels based on the Paris COP21 agreement.

Models, grids, calendars, and pressure levels

Models 

The models included in the CDS-CMIP6 subset are detailed in the table below including a brief description of the model, further details can be found on the Earth System Documentation site (ES-DOC) or WDC-climate pages. Sometimes there are differences between the model details reported in the CMIP6 metadata and the source documentation, the models with such discrepancies are marked here with an asterix and further details are provided in a second table below. The grid IDs reported in the final column are explained further under the 'grids' section.


Model Name

Modelling Centre

Model Details 

Grids on the CDS ('gn', 'gr' or 'gr1')

ACCESS-CM2 (released in 2019)

CSIRO-ARCCSS (Commonwealth Scientific and Industrial Research Organisation, Australian Research Council Centre of Excellence for Climate System Science)

The model includes the components: aerosol: UKCA-GLOMAP-mode, atmos: MetUM-HadGEM3-GA7.1 (N96; 192 x 144 longitude/latitude; 85 levels; top-level 85 km), land: CABLE2.5, ocean: ACCESS-OM2 (GFDL-MOM5, tripolar primarily 1deg; 360 x 300 longitude/latitude; 50 levels; top grid cell 0-10 m), seaIce: CICE5.1.2 (same grid as ocean). The model was run in native nominal resolutions: aerosol: 250 km, atmosphere: 250 km, land: 250 km, ocean: 100 km, seaIce: 100 km.

'gn'

ACCESS-ESM1-5 (released in 2019)

CSIRO (Commonwealth Scientific and Industrial Research Organisation)The model includes the components: aerosol: CLASSIC (v1.0), atmos: HadGAM2 (r1.1, N96; 192 x 145 longitude/latitude; 38 levels; top level 39255 m), land: CABLE2.4, ocean: ACCESS-OM2 (MOM5, tripolar primarily 1deg; 360 x 300 longitude/latitude; 50 levels; top grid cell 0-10 m), ocnBgchem: WOMBAT (same grid as ocean), seaIce: CICE4.1 (same grid as ocean). The model was run in native nominal resolutions: aerosol: 250 km, atmosphere: 250 km, land: 250 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.'gn'

AWI-CM-1-1-MR (released in 2018)

AWI (Alfred Wegener Institute)

The model includes the components: atmos: ECHAM6.3.04p1 (T127L95 native atmosphere T127 gaussian grid; 384 x 192 longitude/latitude; 95 levels; top level 80 km), land: JSBACH 3.20, ocean: FESOM 1.4 (unstructured grid in the horizontal with 830305 wet nodes; 46 levels; top grid cell 0-5 m), seaIce: FESOM 1.4. The model was run in native nominal resolutions: atmos: 100 km, land: 100 km, ocean: 25 km, seaIce: 25 km.

'gn'

AWI-ESM-1-1-LR (released in 2018)

AWI (Alfred Wegener Institute)The model includes the components: atmos: ECHAM6.3.04p1 (T63L47 native atmosphere T63 gaussian grid; 192 x 96 longitude/latitude; 47 levels; top-level 80 km), land: JSBACH 3.20 with dynamic vegetation, ocean: FESOM 1.4 (unstructured grid in the horizontal with 126859 wet nodes; 46 levels; top grid cell 0-5 m), seaIce: FESOM 1.4. AWI-ESM 1.1 LR is an extension of the AWI-CM for earth system modelling. The model was run in native nominal resolutions: atmos: 250 km, land: 250 km, ocean: 50 km, seaIce: 50 km.'gn'

BCC-CSM2-MR (released in 2017)

BCC (Beijing Climate Center)The model includes the components: atmos: BCC_AGCM3_MR (T106; 320 x 160 longitude/latitude; 46 levels; top level 1.46 hPa), land: BCC_AVIM2, ocean: MOM4 (1/3 deg 10S-10N, 1/3-1 deg 10-30 N/S, and 1 deg in high latitudes; 360 x 232 longitude/latitude; 40 levels; top grid cell 0-10 m), seaIce: SIS2. The model was run in native nominal resolutions: atmosphere: 100 km, land: 100 km, ocean: 50 km, seaIce: 50 km.'gn'

BCC-ESM1 (released in 2017)

BCC  (Beijing Climate Center)The model includes the components: atmos: BCC_AGCM3_LR (T42; 128 x 64 longitude/latitude; 26 levels; top level 2.19 hPa), atmosChem: BCC-AGCM3-Chem, land: BCC_AVIM2, ocean: MOM4 (1/3 deg 10S-10N, 1/3-1 deg 10-30 N/S, and 1 deg in high latitudes; 360 x 232 longitude/latitude; 40 levels; top grid cell 0-10 m), seaIce: SIS2. The model was run in native nominal resolutions: atmosphere: 250 km, atmospheric chemistry: 250 km, land: 250 km, ocean: 50 km, seaIce: 50 km.'gn'

CAMS-CSM1-0 (released in 2016)

CAMS (Chinese Academy of Meteorological Sciences)The model includes the components: atmos: ECHAM5_CAMS (T106; 320 x 160 longitude/latitude; 31 levels; top level 10 mb), land: CoLM 1.0, ocean: MOM4 (tripolar; 360 x 200 longitude/latitude, primarily 1deg latitude/longitude, down to 1/3deg within 30deg of the equatorial tropics; 50 levels; top grid cell 0-10 m), seaIce: SIS 1.0. The model was run in native nominal resolutions: atmosphere: 100 km, land: 100 km, ocean: 100 km, seaIce: 100 km.'gn'

CanESM5 (released in 2019)

CCCMA (Canadian Centre for Climate Modelling and Analysis)The model includes the components: aerosol: interactive, atmos: CanAM5 (T63L49 native atmosphere, T63 Linear Gaussian Grid; 128 x 64 longitude/latitude; 49 levels; top-level 1 hPa), atmosChem: specified oxidants for aerosols, land: CLASS3.6/CTEM1.2, landIce: specified ice sheets, ocean: NEMO3.4.1 (ORCA1 tripolar grid, 1 deg with refinement to 1/3 deg within 20 degrees of the equator; 361 x 290 longitude/latitude; 45 vertical levels; top grid cell 0-6.19 m), ocnBgchem: Canadian Model of Ocean Carbon (CMOC); NPZD ecosystem with OMIP prescribed carbonate chemistry, seaIce: LIM2. The model was run in native nominal resolutions: aerosol: 500 km, atmosphere: 500 km, atmospheric chemistry: 500 km, land: 500 km, landIce: 500 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.'gn'

CanESM5-CanOE (released in 2019)

CCCMA (Canadian Centre for Climate Modelling and Analysis)CanESM5-CanOE is identical to CanESM5, except that CMOC (Canadian Model of Ocean Carbon) was replaced with CanOE (Canadian Ocean Ecosystem model). The model was run in native nominal resolutions: aerosol: 500 km, atmos: 500 km, atmosChem: 500 km, land: 500 km, landIce: 500 km, ocean: 100 km, ocnBgchem: 100 km, seaIce: 100 km.'gn'

CESM2

NCAR (National Center for Atmospheric Research)The model includes the components: aerosol: MAM4 (same grid as atmos), atmos: CAM6 (0.9x1.25 finite volume grid; 288 x 192 longitude/latitude; 32 levels; top level 2.25 mb), atmosChem: MAM4 (same grid as atmos), land: CLM5 (same grid as atmos), landIce: CISM2.1, ocean: POP2 (320x384 longitude/latitude; 60 levels; top grid cell 0-10 m), ocnBgchem: MARBL (same grid as ocean), seaIce: CICE5.1 (same grid as ocean). The model was run in native nominal resolutions: aerosol: 100 km, atmos: 100 km, atmosChem: 100 km, land: 100 km, landIce: 5 km, ocean: 100 km, ocnBgchem: 100 km, seaIce: 100 km.'gn'

CESM2-FV2 (released in 2019)

NCAR (National Center for Atmospheric Research)

The model includes the components: aerosol: MAM4 (same grid as atmos), atmos: CAM6 (1.9x2.5 finite volume grid; 144 x 96 longitude/latitude; 32 levels; top level 2.25 mb), atmosChem: MAM4 (same grid as atmos), land: CLM5 (same grid as atmos), landIce: CISM2.1, ocean: POP2 (320x384 longitude/latitude; 60 levels; top grid cell 0-10 m), ocnBgchem: MARBL (same grid as ocean), seaIce: CICE5.1 (same grid as ocean). The model was run in native nominal resolutions: aerosol: 250 km, atmosphere: 250 km, atmospheric chemistry: 250 km, land: 250 km, landIce: 5 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.

'gn'

CESM2-WACCM (released in 2018)*

NCAR (National Center for Atmospheric Research)The model includes the components: aerosol: MAM4 (same grid as atmos), atmos: WACCM6 (0.9x1.25 finite volume grid; 288 x 192 longitude/latitude; 70 levels; top level 4.5e-06 mb), atmosChem: MAM4 (same grid as atmos), land: CLM5 (same grid as atmos), landIce: CISM2.1, ocean: POP2 (320 x 384 longitude/latitude; 60 levels; top grid cell 0-10 m), ocnBgchem: MARBL (same grid as ocean), seaIce: CICE5.1 (same grid as ocean). The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, atmospheric chemistry: 100 km, land: 100 km, landIce: 5 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.'gn'

CESM2-WACCM-FV2 (released in 2019)*

NCAR (National Center for Atmospheric Research)The model includes the components: aerosol: MAM4 (same grid as atmos), atmos: WACCM6 (1.9x2.5 finite volume grid; 144 x 96 longitude/latitude; 70 levels; top level 4.5e-06 mb), atmosChem: MAM4 (same grid as atmos), land: CLM5 (same grid as atmos), landIce: CISM2.1, ocean: POP2 (320x384 longitude/latitude; 60 levels; top grid cell 0-10 m), ocnBgchem: MARBL (same grid as ocean), seaIce: CICE5.1 (same grid as ocean). The model was run in native nominal resolutions: aerosol: 250 km, atmosphere: 250 km, atmospheric chemistry: 250 km, land: 250 km, landIce: 5 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.'gn'

CIESM (released in 2017)*

THU (Tsinghua University - Department of Earth System Science)The model includes the components: aerosol: MAM4, atmos: CIESM-AM (FV/FD; 288 x 192 longitude/latitude; 30 levels; top level 2.255 hPa), atmosChem: trop_mam4, land: CIESM-LM (modified CLM4.5), ocean: CIESM-OM (FD, SCCGrid Displaced Pole; 720 x 560 longitude/latitude; 46 levels; top grid cell 0-6 m), seaIce: CICE4. The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, atmospheric chemistry: 100 km, land: 100 km, ocean: 50 km, seaIce: 50 km.'gn', 'gr'

CMCC-CM2-HR4 (released in 2016)

CMCC (Centro Euro-Mediterraneo per I Cambiamenti Climatici)The model includes the components: aerosol: prescribed MACv2-SP, atmos: CAM4 (1deg; 288 x 192 longitude/latitude; 26 levels; top at ~2 hPa), land: CLM4.5 (SP mode), ocean: NEMO3.6 (ORCA0.25 1/4 deg from the Equator degrading at the poles; 1442 x 1051 longitude/latitude; 50 vertical levels; top grid cell 0-1 m), seaIce: CICE4.0.
The model was run in native nominal resolutions: aerosol: 100 km, atmos: 100 km, land: 100 km, ocean: 25 km, seaIce: 25 km.
'gn'

CMCC-CM2-SR5 (released in 2016)

CMCC (Centro Euro-Mediterraneo per I Cambiamenti Climatici)The model includes the components: aerosol: MAM3, atmos: CAM5.3 (1deg; 288 x 192 longitude/latitude; 30 levels; top at ~2 hPa), land: CLM4.5 (BGC mode), ocean: NEMO3.6 (ORCA1 tripolar primarly 1 deg lat/lon with meridional refinement down to 1/3 degree in the tropics; 362 x 292 longitude/latitude; 50 vertical levels; top grid cell 0-1 m), seaIce: CICE4.0.  The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, land: 100 km, ocean: 100 km, seaIce: 100 km.'gn'

CMCC-ESM2 (released in 2017)

CMCC (Centro Euro-Mediterraneo per I Cambiamenti Climatici)The model includes the components: MAM3, atmos: CAM5.3 (1deg; 288 x 192 longitude/latitude; 30 levels; top at ~2 hPa), land: CLM4.5 (BGC mode), ocean: NEMO3.6 (ORCA1 tripolar primarly 1 deg lat/lon with meridional refinement down to 1/3 degree in the tropics; 362 x 292 longitude/latitude; 50 vertical levels; top grid cell 0-1 m), ocnBgchem: BFM5.2, seaIce: CICE4.0. The model was run in native nominal resolutions: aerosol: 100 km, atmos: 100 km, land: 100 km, ocean: 100 km, ocnBgchem: 100 km, seaIce: 100 km.'gn'

CNRM-CM6-1  (released in 2017)

CNRM-CERFACS (National Center for Meteorological Research, Météo-France and CNRS laboratory, Climate Modeling and Global change)The model includes the components: aerosol: prescribed monthly fields computed by TACTIC_v2 scheme, atmos: Arpege 6.3 (T127; Gaussian Reduced with 24572 grid points in total distributed over 128 latitude circles (with 256 grid points per latitude circle between 30degN and 30degS reducing to 20 grid points per latitude circle at 88.9degN and 88.9degS); 91 levels; top-level 78.4 km), atmosChem: OZL_v2, land: Surfex 8.0c, ocean: Nemo 3.6 (eORCA1, tripolar primarily 1deg; 362 x 294 longitude/latitude; 75 levels; top grid cell 0-1 m), seaIce: Gelato 6.1. The model was run in native nominal resolutions: aerosol: 250 km, atmos: 250 km, atmosChem: 250 km, land: 250 km, ocean: 100 km, seaIce: 100 km.
'gn', gr', 'gr1'

CNRM-CM6-1-HR (released in 2017)

CNRM-CERFACS (National Center for Meteorological Research, Météo-France and CNRS laboratory, Climate Modeling and Global change)The model includes the components: aerosol: prescribed monthly fields computed by TACTIC_v2 scheme, atmos: Arpege 6.3 (T359; Gaussian Reduced with 181724 grid points in total distributed over 360 latitude circles (with 720 grid points per latitude circle between 32.2degN and 32.2degS reducing to 18 grid points per latitude circle at 89.6degN and 89.6degS); 91 levels; top-level 78.4 km), atmosChem: OZL_v2, land: Surfex 8.0c, ocean: Nemo 3.6 (eORCA025, tripolar primarily 1/4deg; 1442 x 1050 longitude/latitude; 75 levels; top grid cell 0-1 m), seaIce: Gelato 6.1. The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, atmospheric chemistry: 100 km, land: 100 km, ocean: 25 km, seaIce: 25 km.'gn', 'gr'

CNRM-ESM2-1 (released in 2017)

CNRM-CERFACS (National Center for Meteorological Research, Météo-France and CNRS laboratory, Climate Modeling and Global change)The model includes the components: aerosol: TACTIC_v2, atmos: Arpege 6.3 (T127; Gaussian Reduced with 24572 grid points in total distributed over 128 latitude circles (with 256 grid points per latitude circle between 30degN and 30degS reducing to 20 grid points per latitude circle at 88.9degN and 88.9degS); 91 levels; top-level 78.4 km), atmosChem: REPROBUS-C_v2, land: Surfex 8.0c, ocean: Nemo 3.6 (eORCA1, tripolar primarily 1deg; 362 x 294 longitude/latitude; 75 levels; top grid cell 0-1 m), ocnBgchem: Pisces 2.s, seaIce: Gelato 6.1. The model was run in native nominal resolutions: aerosol: 250 km, atmos: 250 km, atmosChem: 250 km, land: 250 km, ocean: 100 km, ocnBgchem: 100 km, seaIce: 100 km.'gn', gr', 'gr1'

E3SM-1-0 (released in 2018)

E3SM-Project LLNL (Energy Exascale Earth System Model, Lawrence Livermore National Laboratory)The model includes the components: aerosol: MAM4 with resuspension, marine organics, and secondary organics (same grid as atmos), atmos: EAM (v1.0, cubed sphere spectral-element grid; 5400 elements with p=3; 1 deg average grid spacing; 90 x 90 x 6 longitude/latitude/cubeface; 72 levels; top level 0.1 hPa), atmosChem: Troposphere specified oxidants for aerosols. Stratosphere linearized interactive ozone (LINOZ v2) (same grid as atmos), land: ELM (v1.0, cubed sphere spectral-element grid; 5400 elements with p=3; 1 deg average grid spacing; 90 x 90 x 6 longitude/latitude/cubeface; satellite phenology mode), MOSART (v1.0, 0.5 degree latitude/longitude grid), ocean: MPAS-Ocean (v6.0, oEC60to30 unstructured SVTs mesh with 235160 cells and 714274 edges, variable resolution 60 km to 30 km; 60 levels; top grid cell 0-10 m), seaIce: MPAS-Seaice (v6.0, same grid as ocean). The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, atmospheric chemistry: 100 km, land: 100 km, ocean: 50 km, seaIce: 50 km.'gr'

E3SM-1-1 (released in 2019)

E3SM-Project RUBISCO (Energy Exascale Earth System Model, Reducing Uncertainty in Biogeochemical Interactions through Synthesis and COmputation)The model includes the components: aerosol: MAM4 with resuspension, marine organics, and secondary organics (same grid as atmos), atmos: EAM (v1.1, cubed sphere spectral-element grid; 5400 elements with p=3; 1 deg average grid spacing; 90 x 90 x 6 longitude/latitude/cubeface; 72 levels; top-level 0.1 hPa), atmosChem: Troposphere specified oxidants for aerosols. Stratosphere linearized interactive ozone (LINOZ v2) (same grid as atmos), land: ELM (v1.1, same grid as atmos; active biogeochemistry using the Converging Trophic Cascade plant and soil carbon and nutrient mechanisms to represent carbon, nitrogen and phosphorus cycles), MOSART (v1.1, 0.5 degree latitude/longitude grid), ocean: MPAS-Ocean (v6.0, oEC60to30 unstructured SVTs mesh with 235160 cells and 714274 edges, variable resolution 60 km to 30 km; 60 levels; top grid cell 0-10 m), ocnBgchem: BEC (Biogeochemical Elemental Cycling model, NPZD-type with C/N/P/Fe/Si/O; same grid as ocean), seaIce: MPAS-Seaice (v6.0; same grid as ocean). The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, atmospheric chemistry: 100 km, land: 100 km, ocean: 50 km, ocean biogeochemistry: 50 km, seaIce: 50 km.'gr'

E3SM-1-1-ECA (released in 2019)

E3SM-Project  (Energy Exascale Earth System Model)The model includes the components: aerosol: MAM4 with resuspension, marine organics, and secondary organics (same grid as atmos), atmos: EAM (v1.1, cubed sphere spectral-element grid; 5400 elements with p=3; 1 deg average grid spacing; 90 x 90 x 6 longitude/latitude/cubeface; 72 levels; top-level 0.1 hPa), atmosChem: Troposphere specified oxidants for aerosols. Stratosphere linearized interactive ozone (LINOZ v2) (same grid as atmos), land: ELM (v1.1, same as atmos; active biogeochemistry using the Equilibrium Chemistry Approximation to represent plant and soil carbon and nutrient mechanisms especially carbon, nitrogen and phosphorus limitation), MOSART (v1.1, 0.5 degree latitude/longitude grid), ocean: MPAS-Ocean (v6.0, oEC60to30 unstructured SVTs mesh with 235160 cells and 714274 edges, variable resolution 60 km to 30 km; 60 levels; top grid cell 0-10 m), ocnBgchem: BEC (Biogeochemical Elemental Cycling model, NPZD-type with C/N/P/Fe/Si/O; same grid as ocean), seaIce: MPAS-Seaice (v6.0; same grid as ocean). The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, atmospheric chemistry: 100 km, land: 100 km, ocean: 50 km, ocean biogeochemistry: 50 km, seaIce: 50 km.'gr'

EC-Earth3 (released in 2019)

EC-Earth-ConsortiumThe model includes the components: atmos: IFS cy36r4 (TL255, linearly reduced Gaussian grid equivalent to 512 x 256 longitude/latitude; 91 levels; top-level 0.01 hPa), land: HTESSEL (land surface scheme built-in IFS), ocean: NEMO3.6 (ORCA1 tripolar primarily 1 deg with meridional refinement down to 1/3 degree in the tropics; 362 x 292 longitude/latitude; 75 levels; top grid cell 0-1 m), seaIce: LIM3. The model was run in native nominal resolutions: atmos: 100 km, land: 100 km, ocean: 100 km, seaIce: 100 km.'gn', 'gr'

EC-Earth3-AerChem (released in 2019)

EC-Earth-ConsortiumThe model includes the components: aerosol: M5 (3 x 2 degrees; 120 x 90 longitude/latitude; 34 levels; top level: 0.1 hPa), atmos: IFS cy36r4 (TL255, linearly reduced Gaussian grid equivalent to 512 x 256 longitude/latitude; 91 levels; top level 0.01 hPa), atmosChem: TM5 (3 x 2 degrees; 120 x 90 longitude/latitude; 34 levels; top level: 0.1 hPa), land: HTESSEL (land surface scheme built in IFS), ocean: NEMO3.6 (ORCA1 tripolar primarily 1 degree with meridional refinement down to 1/3 degree in the tropics; 362 x 292 longitude/latitude; 75 levels; top grid cell 0-1 m), seaIce: LIM3.'gn', 'gr'

EC-Earth3-CC  (released in 2019)

EC-Earth-Consortium

The model includes the components: atmos: IFS cy36r4 (TL255, linearly reduced Gaussian grid equivalent to 512 x 256 longitude/latitude; 91 levels; top level 0.01 hPa), atmosChem: TM5 (3 x 2 degrees; 120 x 90 longitude/latitude; 34 levels; top level: 0.1 hPa), land: HTESSEL (land surface scheme built in IFS) and LPJ-GUESS v4, ocean: NEMO3.6 (ORCA1 tripolar primarily 1 degree with meridional refinement down to 1/3 degree in the tropics; 362 x 292 longitude/latitude; 75 levels; top grid cell 0-1 m), ocnBgchem: PISCES v2, seaIce: LIM3. The model was run in native nominal resolutions: atmos: 100 km, atmosChem: 250 km, land: 100 km, ocean: 100 km, ocnBgchem: 100 km, seaIce: 100 km.

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EC-Earth3-Veg (released in 2019)

EC-Earth-ConsortiumThe model includes the components: atmos: IFS cy36r4 (TL255, linearly reduced Gaussian grid equivalent to 512 x 256 longitude/latitude; 91 levels; top-level 0.01 hPa), land: HTESSEL (land surface scheme built-in IFS) and LPJ-GUESS v4, ocean: NEMO3.6 (ORCA1 tripolar primarily 1 degree with meridional refinement down to 1/3 degree in the tropics; 362 x 292 longitude/latitude; 75 levels; top grid cell 0-1 m), seaIce: LIM3. The model was run in native nominal resolutions: atmos: 100 km, land: 100 km, ocean: 100 km, seaIce: 100 km.'gn', 'gr'

EC-Earth3-Veg-LR (released in 2019)

EC-Earth-ConsortiumThe model includes the components: atmos: IFS cy36r4 (TL159, linearly reduced Gaussian grid equivalent to 320 x 160 longitude/latitude; 62 levels; top-level 5 hPa), land: HTESSEL (land surface scheme built-in IFS) and LPJ-GUESS v4, ocean: NEMO3.6 (ORCA1 tripolar primarily 1 degree with meridional refinement down to 1/3 degree in the tropics; 362 x 292 longitude/latitude; 75 levels; top grid cell 0-1 m), seaIce: LIM3. The model was run in native nominal resolutions: atmos: 250 km, land: 250 km, ocean: 100 km, seaIce: 100 km.'gn', 'gr'

FGOALS-f3-L (released in 2017)

CAS (Chinese Academy of Sciences)The model includes the components: atmos: FAMIL2.2 (Cubed-sphere, c96; 360 x 180 longitude/latitude; 32 levels; top level 2.16 hPa), land: CLM4.0, ocean: LICOM3.0 (LICOM3.0, tripolar primarily 1deg; 360 x 218 longitude/latitude; 30 levels; top grid cell 0-10 m), seaIce: CICE4.0. The model was run in native nominal resolutions: atmosphere: 100 km, land: 100 km, ocean: 100 km, seaIce: 100 km.'gn', 'gr'

FGOALS-g3 (released in 2017)*

CAS (Chinese Academy of Sciences)The model includes the components: atmos: GAMIL3 (180 x 80 longitude/latitude; 26 levels; top level 2.19hPa), land: CAS-LSM, ocean: LICOM3.0 (LICOM3.0, tripolar primarily 1deg; 360 x 218 longitude/latitude; 30 levels; top grid cell 0-10 m), seaIce: CICE4.0. The model was run in native nominal resolutions: atmosphere: 250 km, land: 250 km, ocean: 100 km, seaIce: 100 km.'gn'

FIO-ESM-2-0 (released in 2018)

FIO-QLNM (First Institute of Oceanography (FIO) and Qingdao National Laboratory for Marine Science and Technology (QNLM))The model includes the components: aerosol: Prescribed monthly fields, atmos: CAM4 (0.9x1.25 finite volume grid; 192 x 288 longitude/latitude; 26 levels; top level ~2 hPa), land: CLM4.0 (same grid at atmos), ocean: POP2-W (POP2 coupled with MASNUM surface wave model, Displaced Pole; 320 x 384 longitude/latitude; 60 levels; top grid cell 0-10 m), seaIce: CICE4.0 (same grid as ocean). The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, land: 100 km, ocean: 100 km, seaIce: 100 km.'gn'

GFDL-ESM4 (released in 2018)

NOAA-GFDL (National Oceanic and Atmospheric Administration, Geophysical Fluid Dynamics Laboratory)The model includes the components: aerosol: interactive, atmos: GFDL-AM4.1 (Cubed-sphere (c96) - 1 degree nominal horizontal resolution; 360 x 180 longitude/latitude; 49 levels; top level 1 Pa), atmosChem: GFDL-ATMCHEM4.1 (full atmospheric chemistry), land: GFDL-LM4.1, landIce: GFDL-LM4.1, ocean: GFDL-OM4p5 (GFDL-MOM6, tripolar - nominal 0.5 deg; 720 x 576 longitude/latitude; 75 levels; top grid cell 0-2 m), ocnBgchem: GFDL-COBALTv2, seaIce: GFDL-SIM4p5 (GFDL-SIS2.0, tripolar - nominal 0.5 deg; 720 x 576 longitude/latitude; 5 layers; 5 thickness categories). The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, atmospheric chemistry: 100 km, land: 100 km, landIce: 100 km, ocean: 50 km, ocean biogeochemistry: 50 km, seaIce: 50 km.'gr', 'gr1'

GISS-E2-1-G (released in 2019)

NASA-GISS  (National Oceanic and Atmospheric Administration, Goddard Institute for Space Studies)The model includes the components: aerosol: Varies with physics-version (p==1 none, p==3 OMA, p==4 TOMAS, p==5 MATRIX), atmos: GISS-E2.1 (2.5x2 degree; 144 x 90 longitude/latitude; 40 levels; top level 0.1 hPa), atmosChem: Varies with physics-version (p==1 Non-interactive, p>1 GPUCCINI), land: GISS LSM, ocean: GISS Ocean (GO1, 1 degree; 360 x 180 longitude/latitude; 40 levels; top grid cell 0-10 m), seaIce: GISS SI. The model was run in native nominal resolutions: aerosol: 250 km, atmosphere: 250 km, atmospheric chemistry: 250 km, land: 250 km, ocean: 100 km, seaIce: 250 km.'gn'

GISS-E2-1-H (released in 2019)*

NASA-GISS  (National Oceanic and Atmospheric Administration, Goddard Institute for Space Studies)The model includes the components: aerosol: Varies with physics-version (p==1 none, p==3 OMA, p==4 TOMAS, p==5 MATRIX), atmos: GISS-E2.1 (2.5x2 degree; 144 x 90 longitude/latitude; 40 levels; top level 0.1 hPa), atmosChem: Varies with physics-version (p==1 Non-interactive, p>1 GPUCCINI), land: GISS LSM, ocean: HYCOM Ocean (~1 degree tripolar grid; 360 x 180 longitude/latitude; 32 levels; top grid cell 0-10 m), seaIce: GISS SI. The model was run in native nominal resolutions: aerosol: 250 km, atmosphere: 250 km, atmospheric chemistry: 250 km, land: 250 km, ocean: 100 km, seaIce: 250 km.'gn', 'gr'

HadGEM3-GC31-LL (released in 2016)

MOHC NERC (Met Office Hadley Centre, Natural Environmental Research Council)The model includes the components: aerosol: UKCA-GLOMAP-mode, atmos: MetUM-HadGEM3-GA7.1 (N96; 192 x 144 longitude/latitude; 85 levels; top level 85 km), land: JULES-HadGEM3-GL7.1, ocean: NEMO-HadGEM3-GO6.0 (eORCA1 tripolar primarily 1 deg with meridional refinement down to 1/3 degree in the tropics; 360 x 330 longitude/latitude; 75 levels; top grid cell 0-1 m), seaIce: CICE-HadGEM3-GSI8 (eORCA1 tripolar primarily 1 deg; 360 x 330 longitude/latitude). The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, land: 100 km, ocean: 25 km, seaIce: 25 km.'gn', 'gr'

HadGEM3-GC31-MM (released in 2016)

MOHC (Met Office Hadley Centre)The model includes the components: aerosol: UKCA-GLOMAP-mode, atmos: MetUM-HadGEM3-GA7.1 (N216; 432 x 324 longitude/latitude; 85 levels; top level 85 km), land: JULES-HadGEM3-GL7.1, ocean: NEMO-HadGEM3-GO6.0 (eORCA025 tripolar primarily 0.25 deg; 1440 x 1205 longitude/latitude; 75 levels; top grid cell 0-1 m), seaIce: CICE-HadGEM3-GSI8 (eORCA025 tripolar primarily 0.25 deg; 1440 x 1205 longitude/latitude). The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, land: 100 km, ocean: 25 km, seaIce: 25 km.'gn', 'gr'

IITM-ESM  (released in 2015)

CCCR-IITM (Centre for Climate Change Research, Indian Institute of Tropical Meteorology)The model includes the components: aerosol: prescribed MAC-v2, atmos: IITM-GFSv1 (T62L64, Linearly Reduced Gaussian Grid; 192 x 94 longitude/latitude; 64 levels; top level 0.2 mb), land: NOAH LSMv2.7.1, ocean: MOM4p1 (tripolar, primarily 1deg; 360 x 200 longitude/latitude; 50 levels; top grid cell 0-10 m), ocnBgchem: TOPAZv2.0, seaIce: SISv1.0. The model was run in native nominal resolutions: aerosol: 250 km, atmosphere: 250 km, land: 250 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.'gn'

INM-CM4-8 (released in 2016)

INM (Institute of Numerical Mathematics)The model includes the components: aerosol: INM-AER1, atmos: INM-AM4-8 (2x1.5; 180 x 120 longitude/latitude; 21 levels; top level sigma = 0.01), land: INM-LND1, ocean: INM-OM5 (North Pole shifted to 60N, 90E; 360 x 318 longitude/latitude; 40 levels; sigma vertical coordinate), seaIce: INM-ICE1. The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, land: 100 km, ocean: 100 km, seaIce: 100 km.'gr1'

INM-CM5-0 (released in 2016)

INM (Institute of Numerical Mathematics)The model includes the components: aerosol: INM-AER1, atmos: INM-AM5-0 (2x1.5; 180 x 120 longitude/latitude; 73 levels; top level sigma = 0.0002), land: INM-LND1, ocean: INM-OM5 (North Pole shifted to 60N, 90E. 0.5x0.25; 720 x 720 longitude/latitude; 40 levels; vertical sigma coordinate), seaIce: INM-ICE1. The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, land: 100 km, ocean: 50 km, seaIce: 50 km.'gr1'

IPSL-CM5A2-INCA (released in 2019)

IPSL (Institut Pierre‐Simon Laplace)The model includes the components: aerosol: INCA v6 NMHC-AER-S, atmos: LMDZ (APv5; 96 x 96 longitude/latitude; 39 levels; top level 80000 m), atmosChem: INCA v6 NMHC-AER-S, land: ORCHIDEE (IPSLCM5A2.1, Water/Carbon/Energy mode), ocean: NEMO-OPA (v3.6, ORCA2 tripolar primarily 2deg; 182 x 149 longitude/latitude; 31 levels; top grid cell 0-10 m), ocnBgchem: NEMO-PISCES, seaIce: NEMO-LIM2. The model was run in native nominal resolutions:: 500 km, atmos: 500 km, atmosChem: 500 km, land: 500 km, ocean: 250 km, ocnBgchem: 250 km, seaIce: 250 km'gn', 'gr'

IPSL-CM6A-LR (released in 2017)

IPSL (Institut Pierre‐Simon Laplace)The model includes the components: atmos: LMDZ (NPv6, N96; 144 x 143 longitude/latitude; 79 levels; top level 80000 m), land: ORCHIDEE (v2.0, Water/Carbon/Energy mode), ocean: NEMO-OPA (eORCA1.3, tripolar primarily 1deg; 362 x 332 longitude/latitude; 75 levels; top grid cell 0-2 m), ocnBgchem: NEMO-PISCES, seaIce: NEMO-LIM3. The model was run in native nominal resolutions: atmosphere: 250 km, land: 250 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.'gn', 'gr'

KACE-1-0-G (released in 2018)

NIMS-KMA (National Institute of Meteorological Sciences/Korea Met. Administration)The model includes the components: aerosol: UKCA-GLOMAP-mode, atmos: MetUM-HadGEM3-GA7.1 (N96; 192 x 144 longitude/latitude; 85 levels; top level 85 km), land: JULES-HadGEM3-GL7.1, ocean: MOM4p1 (tripolar primarily 1deg; 360 x 200 longitude/latitude; 50 levels; top grid cell 0-10 m), seaIce: CICE-HadGEM3-GSI8 (tripolar primarily 1deg; 360 x 200 longitude/latitude). The model was run in native nominal resolutions: aerosol: 250 km, atmos: 250 km, land: 250 km, ocean: 100 km, seaIce: 100 km.'gr'

KIOST-ESM (released in 2018)

KIOST (Korea Institute of Ocean Science and Technology)The model includes the components: atmos: GFDL-AM2.0 (cubed sphere (C48); 192 x 96 longitude/latitude; 32 vertical levels; top level 2 hPa), atmosChem: Simple carbon aerosol model (emission type), land: NCAR-CLM4, landIce: NCAR-CLM4, ocean: GFDL-MOM5.0 (tripolar - nominal 1.0 deg; 360 x 200 longitude/latitude; 52 levels; top grid cell 0-2 m; NK mixed layer scheme), ocnBgchem: TOPAZ2, seaIce: GFDL-SIS. The model was run in native nominal resolutions: atmosphere: 250 km, atmospheric chemistry: 250 km, land: 250 km, landIce: 250 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.'gr1'

MCM-UA-1-0 (released in 1991)*

UA (University of Arizona - Department of Geosciences)The model includes the components: aerosol: Modifies surface albedoes (Haywood et al. 1997, https://doi.org/10.1175/1520-0442(1997)010<2963:SFVOTN>2.0.CO;2), atmos: R30L14 (3.75 X 2.5 degree (long-lat) configuration; 96 x 80 longitude/latitude; 14 levels; top level 0.015 sigma, 15 mb), land: Standard Manabe bucket hydrology scheme (Manabe 1969, doi: https://doi.org/10.1175/1520-0493(1969)097<0739:CATOC>2.3.CO;2), landIce: Specified location - invariant in time, has high albedo and latent heat capacity, ocean: MOM1.0 (MOM1, 1.875 X 2.5 deg; 192 x 80 longitude/latitude; 18 levels; top grid cell 0-40 m), seaIce: Thermodynamic ice model (free drift dynamics). The model was run in native nominal resolutions: aerosol: 250 km, atmos: 250 km, land: 250 km, landIce: 250 km, ocean: 250 km, seaIce: 250 km.'gn', 'gr'

MIROC6 (released in 2017)

MIROC (Atmosphere and Ocean Research Institute (AORI), Centre for Climate System Research - National Institute for Environmental Studies (CCSR-NIES) and Atmosphere and Ocean Research Institute (AORI))The model includes the components: aerosol: SPRINTARS6.0, atmos: CCSR AGCM (T85; 256 x 128 longitude/latitude; 81 levels; top level 0.004 hPa), land: MATSIRO6.0, ocean: COCO4.9 (tripolar primarily 1deg; 360 x 256 longitude/latitude; 63 levels; top grid cell 0-2 m), seaIce: COCO4.9. The model was run in native nominal resolutions: aerosol: 250 km, atmos: 250 km, land: 250 km, ocean: 100 km, seaIce: 100 km.'gn'

MIROC-ES2L (released in 2018)

MIROC (Atmosphere and Ocean Research Institute (AORI), Centre for Climate System Research - National Institute for Environmental Studies (CCSR-NIES) and Atmosphere and Ocean Research Institute (AORI))The model includes the components: aerosol: SPRINTARS6.0, atmos: CCSR AGCM (T42; 128 x 64 longitude/latitude; 40 levels; top level 3 hPa), land: MATSIRO6.0+VISIT-e ver.1.0, ocean: COCO4.9 (tripolar primarily 1deg; 360 x 256 longitude/latitude; 63 levels; top grid cell 0-2 m), ocnBgchem: OECO ver.2.0; NPZD-type with C/N/P/Fe/O cycles, seaIce: COCO4.9. The model was run in native nominal resolutions: aerosol: 500 km, atmos: 500 km, land: 500 km, ocean: 100 km, ocnBgchem: 100 km, seaIce: 100 km.
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MPI-ESM-1-2-HAM (released in 2017)

HAMMOZ-Consortium (Swiss Federal Institute of Technology Zurich (ETH-Zurich), Max Planck Institute for Meteorology (MPI-M), Forschungszentrum Jülich, University of Oxford, Finnish Meteorological Institute (FMI), Leibniz Institute for Tropospheric Research (IfT) and Center for Climate Systems Modeling (C2SM) at ETH Zurich)The model includes the components: aerosol: HAM2.3, atmos: ECHAM6.3 (spectral T63; 192 x 96 longitude/latitude; 47 levels; top level 0.01 hPa), atmosChem: sulfur chemistry (unnamed), land: JSBACH 3.20, ocean: MPIOM1.63 (bipolar GR1.5, approximately 1.5deg; 256 x 220 longitude/latitude; 40 levels; top grid cell 0-12 m), ocnBgchem: HAMOCC6, seaIce: unnamed (thermodynamic (Semtner zero-layer) dynamic (Hibler 79) sea ice model). The model was run in native nominal resolutions: aerosol: 250 km, atmos: 250 km, atmosChem: 250 km, land: 250 km, ocean: 250 km, ocnBgchem: 250 km, seaIce: 250 km.'gn'

MPI-ESM1-2-HR (released in 2017)

MPI-M DWD DKRZ (Max Planck Institute for Meteorology (MPI-M), German Meteorological Service (DWD), German Climate Computing Center (DKRZ))The model includes the components: aerosol: none, prescribed MACv2-SP, atmos: ECHAM6.3 (spectral T127; 384 x 192 longitude/latitude; 95 levels; top level 0.01 hPa), land: JSBACH3.20, landIce: none/prescribed, ocean: MPIOM1.63 (tripolar TP04, approximately 0.4deg; 802 x 404 longitude/latitude; 40 levels; top grid cell 0-12 m), ocnBgchem: HAMOCC6, seaIce: unnamed (thermodynamic (Semtner zero-layer) dynamic (Hibler 79) sea ice model). The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, land: 100 km, landIce: none, ocean: 50 km, ocean biogeochemistry: 50 km, seaIce: 50 km.'gn'

MPI-ESM1-2-LR (released in 2017)

MPI-M AWI (Max Planck Institute for Meteorology (MPI-M), AWI (Alfred Wegener Institute))The model includes the components: aerosol: none, prescribed MACv2-SP, atmos: ECHAM6.3 (spectral T63; 192 x 96 longitude/latitude; 47 levels; top level 0.01 hPa), land: JSBACH3.20, landIce: none/prescribed, ocean: MPIOM1.63 (bipolar GR1.5, approximately 1.5deg; 256 x 220 longitude/latitude; 40 levels; top grid cell 0-12 m), ocnBgchem: HAMOCC6, seaIce: unnamed (thermodynamic (Semtner zero-layer) dynamic (Hibler 79) sea ice model). The model was run in native nominal resolutions: aerosol: 250 km, atmosphere: 250 km, land: 250 km, landIce: none, ocean: 250 km, ocean biogeochemistry: 250 km, seaIce: 250 km.'gn'

MRI-ESM2-0 (released in 2017)

MRI (Meteorological Research Institute, Japan)The model includes the components: aerosol: MASINGAR mk2r4 (TL95; 192 x 96 longitude/latitude; 80 levels; top level 0.01 hPa), atmos: MRI-AGCM3.5 (TL159; 320 x 160 longitude/latitude; 80 levels; top level 0.01 hPa), atmosChem: MRI-CCM2.1 (T42; 128 x 64 longitude/latitude; 80 levels; top level 0.01 hPa), land: HAL 1.0, ocean: MRI.COM4.4 (tripolar primarily 0.5 deg latitude/1 deg longitude with meridional refinement down to 0.3 deg within 10 degrees north and south of the equator; 360 x 364 longitude/latitude; 61 levels; top grid cell 0-2 m), ocnBgchem: MRI.COM4.4, seaIce: MRI.COM4.4. The model was run in native nominal resolutions: aerosol: 250 km, atmosphere: 100 km, atmospheric chemistry: 250 km, land: 100 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.'gn', 'gr'

NESM3 (released in 2016)

NUIST (Nanjing University of Information Science and Technology) The model includes the components: atmos: ECHAM v6.3 (T63; 192 x 96 longitude/latitude; 47 levels; top level 1 Pa), land: JSBACH v3.1, ocean: NEMO v3.4 (NEMO v3.4, tripolar primarily 1deg; 384 x 362 longitude/latitude; 46 levels; top grid cell 0-6 m), seaIce: CICE4.1. The model was run in native nominal resolutions: atmosphere: 250 km, land: 2.5 km, ocean: 100 km, seaIce: 100 km.'gn'

NorCPM1 (released in 2019)

NCC (Norwegian Climate Centre)The model includes the components: aerosol: OsloAero4.1 (same grid as atmos), atmos: CAM-OSLO4.1 (2 degree resolution; 144 x 96 longitude/latitude; 26 levels; top level ~2 hPa), atmosChem: OsloChemSimp4.1 (same grid as atmos), land: CLM4 (same grid as atmos), ocean: MICOM1.1 (1 degree resolution; 320 x 384 longitude/latitude; 53 levels; top grid cell 0-2.5 m [native model uses hybrid density and generic upper-layer coordinate interpolated to z-level for contributed data]), ocnBgchem: HAMOCC5.1 (same grid as ocean), seaIce: CICE4 (same grid as ocean). The model was run in native nominal resolutions: aerosol: 250 km, atmosphere: 250 km, atmospheric chemistry: 250 km, land: 250 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.'gn'

NorESM2-LM (released in 2017)

NCC (Norwegian Climate Centre)The model includes the components: aerosol: OsloAero, atmos: CAM-OSLO (2 degree resolution; 144 x 96; 32 levels; top level 3 mb), atmosChem: OsloChemSimp, land: CLM, landIce: CISM, ocean: MICOM (1 degree resolution; 360 x 384; 70 levels; top grid cell minimum 0-2.5 m [native model uses hybrid density and generic upper-layer coordinate interpolated to z-level for contributed data]), ocnBgchem: HAMOCC, seaIce: CICE. The model was run in native nominal resolutions: aerosol: 250 km, atmospheric: 250 km, atmospheric chemistry: 250 km, land: 250 km, landIce: 250 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.'gn'

NorESM2-MM (released in 2017)

NCC (Norwegian Climate Centre)The model includes the components: aerosol: OsloAero, atmos: CAM-OSLO (1 degree resolution; 288 x 192; 32 levels; top level 3 mb), atmosChem: OsloChemSimp, land: CLM, landIce: CISM, ocean: MICOM (1 degree resolution; 360 x 384; 70 levels; top grid cell minimum 0-2.5 m [native model uses hybrid density and generic upper-layer coordinate interpolated to z-level for contributed data]), ocnBgchem: HAMOCC, seaIce: CICE. The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, atmospheric chemistry: 100 km, land: 100 km, landIce: 100 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.'gn'

SAM0-UNICON (released in 2017)

SNU (Seoul National University)

The model includes the components: aerosol: MAM3, atmos: CAM5.3 with UNICON (1deg; 288 x 192 longitude/latitude; 30 levels; top level ~2 hPa), land: CLM4.0, ocean: POP2 (Displaced Pole; 320 x 384 longitude/latitude; 60 levels; top grid cell 0-10 m), seaIce: CICE4.0. The model was run in native nominal resolutions: aerosol: 100 km, atmos: 100 km, land: 100 km, ocean: 100 km, seaIce: 100 km.'gn'

TaiESM1 (released in 2018)

AS-RCEC (Research Center for Environmental Changes)The model includes the components: aerosol: SNAP (same grid as atmos), atmos: TaiAM1 (0.9x1.25 degree; 288 x 192 longitude/latitude; 30 levels; top level ~2 hPa), atmosChem: SNAP (same grid as atmos), land: CLM4.0 (same grid as atmos), ocean: POP2 (320x384 longitude/latitude; 60 levels; top grid cell 0-10 m), seaIce: CICE4. The model was run in native nominal resolutions: aerosol: 100 km, atmosphere: 100 km, atmospheric chemistry: 100 km, land: 100 km, ocean: 100 km, seaIce: 50 km.'gn'

UKESM1-0-LL (released in 2018)

MOHC, NERC, NIMS-KMA, NIWA  (Met Office Hadley Centre, Natural Environmental Research Council,  National Institute of Meteorological Science / Korean Meteorological Administration (NIMS-KMA), National Institute of Weather and Atmospheric Research (NIWA)) The model includes the components: aerosol: UKCA-GLOMAP-mode, atmos: MetUM-HadGEM3-GA7.1 (N96; 192 x 144 longitude/latitude; 85 levels; top level 85 km), atmosChem: UKCA-StratTrop, land: JULES-ES-1.0, ocean: NEMO-HadGEM3-GO6.0 (eORCA1 tripolar primarily 1 deg with meridional refinement down to 1/3 degree in the tropics; 360 x 330 longitude/latitude; 75 levels; top grid cell 0-1 m), ocnBgchem: MEDUSA2, seaIce: CICE-HadGEM3-GSI8 (eORCA1 tripolar primarily 1 deg; 360 x 330 longitude/latitude). The model was run in native nominal resolutions: aerosol: 250 km, atmosphere: 250 km, atmospheric chemistry: 250 km, land: 250 km, ocean: 100 km, ocean biogeochemistry: 100 km, seaIce: 100 km.
'gn', 'gr'


CMIP6 models where there is a discrepancy between some model details reported in the available documentation and the metadata:

Model Name

Model details (WDC-Climate CMIP6 documentation)

Model details (CMIP6 data files metadata) 

CESM2-WACCM

atmos: WACCM6 (0.9x1.25 finite volume grid; 288 x 192 longitude/latitude; 70 levels; top level 4.5e-06 mb)

atmosphere: CAM6 (0.9x1.25 finite volume grid; 288 x 192 longitude/latitude; 70 levels; top level 4.5e-6 mb)

CESM2-WACCM-FV2 

atmos: WACCM6 (0.9x1.25 finite volume grid; 288 x 192 longitude/latitude; 70 levels; top level 4.5e-06 mb)

atmosphere: CAM6 (0.9x1.25 finite volume grid; 288 x 192 longitude/latitude; 70 levels; top level 4.5e-6 mb)

CIESM 

aerosol: MAM4

atmos: CIESM-AM (FV/FD; 288 x 192 longitude/latitude; 30 levels; top level 2.255 hPa), 

atmosChem: trop_mam4

land: CIESM-LM (modified CLM4.5),

ocean: CIESM-OM (FD, SCCGrid Displaced Pole; 720 x 560 longitude/latitude; 46 levels; top grid cell 0-6 m)

aerosol: prescribed MACv2-SP

atmos: CIESM-AM1.0 (Modified CAM5; 1 degree spectral element; 48602 cells; 30 levels; top level 2.255 hPa)

atmosChem: none

land: CIESM-LM1.0 (Modified CLM4.0)

ocean: CIESM-OM1.0 (Modified POP2; 320 x 384 longitude/latitude; 60 levels; top grid cell 0-10 m)

FGOALS-g3 

atmos: GAMIL3 (180 x 80 longitude/latitude; 26 levels; top level 2.19hPa), 

land: CAS-LSM

atmos: GAMIL2 (180 x 90 longitude/latitude; 26 levels; top level 2.19hPa)

land: CLM4.0

GISS-E2-1-H

Released in 2019

Released in 2016

MCM-UA-1-0


No model details in metadata

Grids

CMIP6 data is available either on the model’s native grid or re-gridded to one or more target grids with data variables generally provided near the centre of each grid cell (rather than at the boundaries). This re-gridding is normally done for models which use native grids other than regular lat-lon grids (e.g. cubed sphere or gaussian), in these cases the output has been re-gridded to a regular lat-lon grid by the modelling centers. For CMIP6 there is a requirement to record both the native grid of the model, and the approximate resolution of the final output data (archived in the CMIP6 repository, and available via the CDS) as a “nominal_resolution”.  This "nominal_resolution” enables users to identify which models have relatively high resolution output. Information about the grids can be found in the model table above, under 'Model Details', and within the NetCDF file metadata.

The column 'Grids on the CDS ('gn', 'gr' or 'gr1')' lists which grid IDs are associated with the data from that model available on the CDS. These labels reflect whether a given set of model data (variable) uploaded to ESGF is on the 

  • native grid of the model component ('gn'),
  • regridded to the regular target grid specified for the particular variable ('gr'),
  • or another target grid ('gr1').

The output from some models has multiple different grid IDs associated with it, due to different model components (atmosphere, land, ocean, cryosphere etc.) being treated differently. This does not necessarily mean the data itself is on a different grid, for example the atmospheric variables maybe on a regular native grid ('gn'), and the ocean variables with an irregular native grid may have been regridded to the atmosphere grid (hence are labelled 'gr'), so they are on the same grid in spite of the fact that their grid ID is different. On the other hand, if a model is only listed as having output on the native grid ('gn'), this does not guarantee that all the data (variable) is on the same grid, as the native grid for different model components can be different.

Note: some data (i.e. variables) have been submitted to ESGF on multiple grids, in these cases only one grid is made available on the CDS (this is decided on a case-by-case basis).

Calendars

Climate models sometime use different calendars, for example Hadley Centre models in CMIP6 use a 360 day calendar, where every month has exactly 30 days. Some models use a fixed 365-day calendar, and others include leap-years. These variations can result in different length time-dimensions if daily data is downloaded, depending on the time period and models selected, or even failed data requests. Users need to be careful, when using the CDS user interface download form or API, to avoid selecting days which may not be available in the calendar of the given model (for example requests referring to day 31 for the Hadley Centre models would fail, because they have a 360 day calendar). The CDS form for CMIP6 currently assumes a standard calendar, so allows the selection of such missing days, and conversely may not allow selection of all days from models with non-standard calendars (but this data can be retrieved using the API). 

Pressure levels

For pressure level data the model output is available on the pressure levels according to the table below. Note that since the model output is standardised all models produce the data on the same pressure levels.

Frequency

Number of Levels

Pressure Levels (hPa)

Daily

8

1000., 850., 700., 500., 250., 100., 50., 10.

Monthly

19

1000., 925., 850., 700., 600., 500., 400., 300., 250., 200., 150., 100., 70., 50., 30., 20., 10., 5., 1.

Ensembles

Each modelling centre typically run the same experiment using the same model with slightly different settings several times to confirm the robustness of results and inform sensitivity studies through the generation of statistical information. A model and its collection of runs is referred to as an ensemble. Within these ensembles, four different categories of sensitivity studies are done, and the resulting individual model runs are labelled by four integers indexing the experiments in each category

e.g. r<W>i<X>p<Y>f<Z>, where W, X, Y and Z are positive integers as defined below:

  • The first category, labelled realization_index (referred to with letter r), performs experiments which differ only in random perturbations of the initial conditions of the experiment. Comparing different realizations allow estimation of the internal variability of the model climate.
  • The second category, labelled initialization_index (referred to with letter i), refers to variation in initialisation parameters. Comparing differently initialised output provides an estimate of how sensitive the model is to initial conditions.
  • The third category, labelled physics_index (referred to with letter p), refers to variations in the way in which sub-grid scale processes are represented. Comparing different simulations in this category provides an estimate of the structural uncertainty associated with choices in the model design.
  • The fourth category labelled forcing_index (referred to with letter f) is used to distinguish runs of a single CMIP6 experiment, but with different forcings applied.

Parameter listings

Time-Independent parameters are marked with a dash in the time resolution column. Please note that some parameters defined at pressure levels, such as 1000 hPa temperature, may contain missing data where they are not defined (so the fields look incomplete over terrain) or are filled with interpolated values (different modelling centres may have different approaches). This happens when the pressure level falls below the orography.

CDS parameter name for CMIP6Time resolution available

 ESGF variable id

CDS parameter name for CMIP5

 Units

Near-surface air temperaturemonthly, daily

 tas

2m temperature

Kelvin

Daily maximum near-surface air temperaturemonthly, daily

 tasmax

Maximum 2m temperature in the last 24 hours

Kelvin

Daily minimum near-surface air temperaturemonthly, daily

 tasmin

Minimum 2m temperature in the last 24 hours 

Kelvin

Surface temperaturemonthlytsSkin temperatureKelvin
Sea level pressuremonthly, dailypslMean sea level pressurePa
Surface air pressuremonthlypsSurface pressurePa
Eastward near-surface windmonthlyuas10m u component of winds-1
Northward near-surface windmonthlyvas10m v component of winds-1
Near-surface wind speedmonthly, dailysfcWind10m wind speeds-1
Near-surface relative humiditymonthlyhurs2m relative humidity1
Near-surface specific humiditymonthly, dailyhuss2m specific humidity1
Precipitationmonthly, dailyprMean precipitation fluxkg m-2s-1
Snowfall fluxmonthlyprsnSnowfall

kg m-2 s-1

Evaporation Including sublimation and transpirationmonthlyevspsblEvaporation

kg m-2 s-1

Surface downward eastward wind stressmonthlytauuEastward turbulent surface stressPa
Surface downward northward wind stressmonthlytauvNorthward turbulent surface stressPa
Surface upward latent heat fluxmonthlyhflsSurface latent heat fluxW m-2
Surface upward sensible heat fluxmonthlyhfssSurface sensible heat fluxW m-2 
Surface downwelling longwave radiationmonthlyrldsSurface thermal radiation downwardsW m-2
Surface upwelling longwave radiationmonthlyrlus

Surface upwelling longwave radiation

W m-2
Surface downwelling shortwave radiationmonthlyrsds

Surface solar radiation downwards

W m-2
Surface upwelling shortwave radiationmonthlyrsus

Surface upwelling shortwave radiation

W m-2
TOA incident shortwave radiationmonthlyrsdt

TOA incident solar radiation

W m-2
TOA outgoing shortwave radiationmonthlyrsutTOA outgoing shortwave radiationW m-2
TOA outgoing longwave radiationmonthlyrlutTOA outgoing longwave radiationW m-2
Total cloud cover percentagemonthlycltTotal cloud cover%
Air temperaturemonthlytaAir temperatureK
Eastward windmonthlyuaU-component of winds-1
Northward windmonthlyvaV-component of winds-1
Relative humiditymonthlyhurRelative humidity1
Specific humiditymonthlyhusSpecific humidity 1
Geopotential heightmonthlyzgGeopotential heightm
Surface snow amountmonthlysnwSurface snow amountkg m-2
Snow depthmonthlysndSnow depthm
Total runoffmonthlymrroRunoffkg m-2 s-1
Moisture in upper portion of soil columnmonthlymrsosSoil moisture contentkg m-2
Sea-Ice area percentage (ocean grid)monthlysiconcSea-ice area percentage1
Sea Ice thicknessmonthlysithickSea ice thicknessm
Sea-Ice mass per areamonthlysimassSea ice plus snow amountkg m-2
Surface temperature of sea IcemonthlysitemptopSea ice surface temperatureK
Sea surface temperaturemonthlytosSea surface temperatureK
Sea surface salinitymonthlysosSea surface salinityPSU
Sea surface height above geoidmonthlyzosSea surface height above geoidm
Grid-cell area for ocean variables-areacelloNOT AVAILABLEm2
Sea floor depth below geoid-depthoNOT AVAILABLEm
Sea area percentage-sftofNOT AVAILABLE%
Grid-cell area for atmospheric grid variables-areacellaNOT AVAILABLEm2
Capacity of soil to store water (field capacity)-mrsofcNOT AVAILABLEkg m-2
Percentage of the grid cell occupied by land (including lakes)-sftlfNOT AVAILABLE%
Land ice area percentage-sftgifNOT AVAILABLE1
Surface altitude-orogNOT AVAILABLEm

Data Format

The CDS subset of CMIP6 data are provided as NetCDF files. NetCDF (Network Common Data Form) is a file format that is freely available and commonly used in the climate modelling community. See more details:  What are NetCDF files and how can I read them

 A CMIP6 NetCDF file in the CDS contains:

  • Global metadata: these fields can describe many different aspects of the file such as
    • when the file was created
    • the name of the institution and model used to generate the file
    • Information on the horizontal grid and regridding procedure
    • links to peer-reviewed papers and technical documentation describing the climate model,
    • links to supporting documentation on the climate model used to generate the file,
    • software used in post-processing.
  • variable dimensions: such as time, latitude, longitude and height
  • variable data: the gridded data
  • variable metadata: e.g. the variable units, averaging period (if relevant) and additional descriptive data

File naming conventions

When you download a CMIP6 file from the CDS it will have a naming convention that is as follows:

<variable_id>_<table_id>_<source_id>_<experiment_id>_<variant_label>_<grid_label>_<time_range>.nc

 Where:

  • variable_id: variable is a short variable name, e.g. “tas” for “temperature at the surface”.
  • table_id: this refers to the MIP table being used. The MIP tables are used to organise the variables. For example, Amon refers to monthly atmospheric variables and Oday contains daily ocean data.
  • source_id: this refers to the model used that produced the data.
  • experiment_id: refers to the set of experiments being run for CMIP6. For example, PiControl, historical and 1pctCO2 (1 percent per year increase in CO2).
  • variant_label: is a label constructed from 4 indices (ensemble identifiers) r<W>i<X>p<Y>f<Z>, where W, K, Y and Z are integers.
  • grid_label: this describes the model grid used. For example, global mean data (gm), data reported on a model's native grid (gn) or regridded data reported on a grid other than the native grid and other than the preferred target grid (gr1).
  • time_range: the temporal range is in the form YYYYMM[DDHH]-YYYY[MMDDHH], where Y is year, M is the month, D is day and H is hour. Note that day and hour are optional (indicated by the square brackets) and are only used if needed by the frequency of the data. For example, daily data from the 1st of January 1980 to the 31st of December 2010 would be written 19800101-20101231.

Quality control of the CDS-CMIP6 subset

The CDS subset of the CMIP6 data have been through a set of quality control checks before being made available through the CDS. The objective of the quality control process is to ensure that all files in the CDS meet a minimum standard. Data files were required to pass all stages of the quality control process before being made available through the CDS. Data files that fail the quality control process are excluded from the CDS-CMIP6 subset, data providers are contacted and if they are able to release a new version of the data with the error corrected then providing this data passes all remaining QC steps may be available for inclusion in the next CMIP6 data release.

 The main aim of the quality control procedure is to check for metadata and gross data errors in the CMIP6 files and datasets. A brief description of each of the QC checks is provided here:

  1. CF-Checks: The CF-checker tool checks that each NetCDF4 file in a given dataset is compliant with the Climate and Forecast (CF) conventions, compliance ensures that the files are interoperable across a range of software tools. When CF-checker 1.7 is run on the current data some remaining issues are highlighted, particularly for lat, lon and time bounds.
  2. PrePARE: The PrePARE software tool is provided by PCMDI (Program for Climate Model Diagnosis and Intercomparison) to verify that CMIP6 files conform to the CMIP6 data protocol. All CMIP6 data should meet this required standard however this check is included to ensure that all data supplied to the CDS have passed this QC test.
  3. nctime: The nctime checker checks the temporal axis of the NetCDF files. For each NetCDF file the temporal element of the file is compared with the time axis data within the file to ensure consistency. For a time-series of data comprised of several NetCDF files nctime ensures that the entire timeseries is complete, that there are no temporal gaps or overlaps in either the filename or in the time axes within the files.
  4. Errata: The dataset was checked to ensure that no outstanding Errata record existed at the time of publication.
  5. Data Ranges: A set of tests on the extreme values of the variables are performed, this is used to ensure that the values of the variables fall into physically realistic ranges.
  6. Handle record consistency checks: This check ensures that the version of the dataset used is the most recently published dataset by the modelling centre, it also checks for any inconsistency in the ESGF publication and excludes any datasets that may have inconsistent high-level metadata.
  7. Exists at all partner sites: It is asserted that each dataset exists at all partner sites: DKRZ and IPSL. 

It is important to note that passing these quality control tests should not be confused with validity: for example, it will be possible for a file to pass all QC steps but contain errors in the data that have not been identified by either data providers or data users.

 In cases where the quality control picks up errors that are related to minor technical details of the conventions, or behavior that is in line with expectations for climate model output despite being unexpected in a physical system, the data will be published with details of the errors referenced in the documentation. An example of the 2nd type of error is given by negative salinity values which occur in one model as a result of rapid release of fresh water from melting sea-ice. These negative values are part of the noise associated with the numerical simulation and reflect what is happening in the numerical model.

Citation, license and PID information

In general the CMIP6 data Citation Service provides information for users on how to cite CMIP6 data and also information on the data licenses.

The users can decide on what level they want to refer to the CMIP6 datasets. 

The highest level is the one provided by the CDS with the use of the following DOI: 10.24381/cds.c866074c (available also at the right-hand-side of the entry). The users can refer to any data with this DOI, which are available in the CMIP6 catalogue entry in the CDS.

The CMIP6 citation Search is at http://bit.ly/CMIP6_Citation_Search. Citations for CDS CMIP6 data available in the CDS are discoverable in the ESGF on model and experiment levels (please note that these linked files are csv files, which can be looked at after downloading them). 

The CMIP6 datasets are also labelled by the so called Persistent Identifiers (PIDs). PIDs are assigned to each version of every file and dataset. These are unique identifiers of the data and they are available in the header of the netcdf datafiles. The PIDs are also provided on dataset and file levels (please note that these files are csv files, which can be looked at after downloading them).

Known issues

CDS users are directed to the CMIP6 ES-DOC Errata Service for known issues with the wider CMIP6 data pool. Data that is provided to the CDS either should not contain any errors, or minor errors should be listed in the Errata Service. Additionally, the Errata Service is also a useful resource for CDS users as data may have been withheld from the CDS for justifiable reasons. Since the current CMIP6 data in the CDS was prepared in late 2020/early 2021, some data may have been updated or removed on ESGF since then. Please note that the IPCC and C3S Atlas datasets published later included additional rigorous quality control, so the CMIP6 data there are not affected by any inconsistencies mentioned below. 

Some Errata entries, or withdrawn data, which affect the data currently available from the CDS are listed in the expandable table below. Note that the ESGF withdrawals listed are cases where there are no longer any versions of that data on ESGF, but it does not identify cases where there is a new version available on ESGF. 

Model

Errata link (if available)

Summary

AWI-ESM-1-1-LR


For the historical experiment, the daily psl data has been removed from ESGF but is still available on the CDS.

CESM2, CESM2-WACCM

https://errata.ipsl.fr/static/view.html?uid=3626030c-fd21-8e59-8bea-87c2c5a9f47cDue to a model configuration error, monthly tasmin and tasmax were erroneously calculated as averages instead of minima and maxima. 

EC-Earth3 


The following data is no longer available from ESGF but are still available on the CDS:

  • ssp434 - all variables
  • sssp534-over - all variables
  • ssp245 - deptho
  • ssp585 - deptho
  • hist - deptho
EC-Earth3-Veg

The following data are no longer on ESGF but are still available on the CDS:

  • hist - deptho
  • ssp119 - sos

NORCPM1

https://errata.ipsl.fr/static/view.html?uid=ad9e4213-f254-e930-a143-030a4b0f8a32The historical experiment was mistakenly used to store output from both historical and historical-ext experiment. They aggregated the cmor-ized historical output into the time chunks 1850-2014, 2015-2018 and 2019-2029. They advise users to regard the last two as unofficial and to ignore them if not intended as baseline for dcppA-hindcast/dcppA-assim.

NorESM2-MM

https://errata.ipsl.fr/static/view.html?uid=0d833fdb-7ee4-4520-b40c-d7e7a0dda8bcAn extension of the ssp585 scenario was published. The whole MIP ScenarioMIP with Source NorESM2-MM and experiment ssp585 was withdrawn from ESGF and republished. The data on the CDS is not compromised, it just covers a limited time range compared to the new data.

Some models on the CDS currently have either missing historical or scenario data for some variables (which is in the process of being resolved).

Note that emission scenario experiments from a model should not be used without the corresponding historical experiments, which are needed to understand model biases. 

Some details are given in the expandable tables below. Please consider these cases carefully (the corresponding historical experiment data may be available on ESGF).

Model

Affected variables

BCC-CSM2-MR

multiple variables

CAMS-CSM1-0

multiple variables

CanESM5

multiple variables

CNRM-CM6-1

multiple variables

CNRM-CM6-1-HR

ua and va

EC-Earth3

all variables (other than fixed fields)

EC-Earth3-CC

monthly hfss and rdls

EC-Earth3-Veg

all variables (other than fixed fields)

EC-Earth3-Veg-LR

multiple variables

E3SM-1-1

multiple variables

FGOALS-g3

monthly siconc and sitemptop

GISS-E2-1-G

multiple variables

IITM-ESMmonthly ps and daily psl and tasmax/tasmin
INM-CM4-8monthly hurs
INM-CM5-0monthly hurs
IPSL-CM6A-LRmultiple variables

MPI-ESM-1-2-HAM

all variables (other than fixed fields)

NorESM2-LM

multiple variables

UKESM1-0-LL

 multiple variables

There are cases listed below, where there is no corresponding scenario data for the historical experiments available for the given model. This limits the potential applications of the data, but users can use the historical simulations alone without scenario simulations. 

Model

AWI-ESM-1-1-LR
BCC-ESM1
CESM2-FV2
CESM2-WACCM-FV2
CMCC-CM2-HR4
EE3SM-1-1-ECA
GISS-E2-1-H
MIROC-ES2H
MPI-ESM1-2-HR
NorCPM1
SAM0-UNICON

Finally, we have identified some cases where the variant_id, or ripf identifier, is not consistent across the historical data and scenarios. When used, these data should be carefully checked for discontinuities at the transition from historical to scenario data.

Model

Affected scenario and variables

BCC-CSM2-MR

historical - multiple variables 

CAMS-CSM1-0

historical - monthly mrsos
CNRM-ESM2-1ssp534-over - all variables
GISS-E2-1-G

historical - all variables 

CESM2historical - all variables 
UKESM1-0-LLhistorical - multiple variables 
MCM-UA-1-0historical - all variables 

Subsetting and downloading data

CDS users will now be able to apply temporal and spatial subsetting operations to CMIP6 datasets. This mechanism (the "roocs" WPS framework) that runs at each of the partner sites: DKRZ and IPSL. The WPS can receive requests for processing based on dataset identifiers, a temporal range, a bounding box and a range of vertical levels. Each request is converted to a job that is run asynchronously on the processing servers at the partner sites. NetCDF files are generated and the response contains download links to each of the files. Users of the CDS will be able to make subsetting selections using the web forms provided by the CDS catalogue web-interface. More advanced users will be able to define their own API requests in the CDS Toolbox that will call the WPS. Output files will be automatically retrieved so that users can access them directly within the CDS.

When CMIP6 data is downloaded from the Climate Data Store, information about any additional processing applied to the data (such as temporal or spatial subsetting) is included in both PNG and JSON form. These provenance files will be zipped up with the retrieved data and named provenance.png and provenance.json, which describe the software used and the methods applied to the data following the W3C PROV standard. For more information about how to interpret these files, please see https://rook-wps.readthedocs.io/en/latest/prov.html.

Additional resources

A training resource in python is available via a Jupyter Notebook on the C3S data tutorials page here: https://ecmwf-projects.github.io/copernicus-training-c3s/projections-cmip6.html

References

Durack, P J. (2020) CMIP6_CVs. v6.2.53.5. Available at: https://github.com/WCRP-CMIP/CMIP6_CVs (Accessed: 26 October 2020).

Eyring, V. et al. (2016) ‘Overview of the Coupled Model Intercomparison Project Phase 6 (CMIP6) experimental design and organization’, Geoscientific Model Development, 9(5), pp. 1937–1958. doi: 10.5194/gmd-9-1937-2016.

IPCC (2020) Sixth Assessment Report. Available at: https://www.ipcc.ch/assessment-report/ar6/ (Accessed: 26 October 2020).

Moss, R. et al. (2008) ‘Towards New Scenarios for Analysis of Emissions, Climate Change, Impacts, and Response Strategies’, Intergovernmental Panel on Climate Change, Geneva, pp. 132.

O’Neill, B.C. et al. (2014) ‘A new scenario framework for climate change research: the concept of shared socioeconomic pathways.’, Climatic Change, 122, pp. 387–400. doi: https://doi.org/10.1007/s10584-013-0905-2

World Climate Research Programme (2020) CMIP Phase 6 (CMIP6): Overview CMIP6 Experimental Design and Organization. Available at: https://www.wcrp-climate.org/wgcm-cmip/wgcm-cmip6 (Accessed: 2 November 2020).


This document has been produced in the context of the Copernicus Climate Change Service (C3S).

The activities leading to these results have been contracted by the European Centre for Medium-Range Weather Forecasts, operator of C3S on behalf of the European Union (Delegation Agreement signed on 11/11/2014 and Contribution Agreement signed on 22/07/2021). All information in this document is provided "as is" and no guarantee or warranty is given that the information is fit for any particular purpose.

The users thereof use the information at their sole risk and liability. For the avoidance of all doubt , the European Commission and the European Centre for Medium - Range Weather Forecasts have no liability in respect of this document, which is merely representing the author's view.