Cloud Feedback Model Intercomparison Project(CFMIP) update

Christopher S. Bretherton, University of Washingtonon behalf of the CFMIP steering committee

CFMIP steering committee:

• Tim Andrews (Met Office)• Chris Bretherton (U. Washington)• Yen-Ting Hwang (National Taiwan University)• Jen Kay (U. Colorado)• Steve Klein (LLNL)• Thorsten Mauritsen (MPI)• George Tselioudis (GISS)• Masahiro Watanabe (U. Tokyo)• Mark Webb (Met Office)

Thanks especially to Masa for hosting and leading the organization of this meeting!

CFMIP web site:https://www.earthsystemcog.org/projects/cfmip/

CFMIP activities

CFMIP is a WCRP endorsed project started in 2003 to improve the understanding and evaluation of clouds, cloud feedbacks and changes in regional-scale circulation and precipitation:

1. CMIP-endorsed standardized idealized experiments for GCMs (abrupt4xCO2, amip4K, amip4xCO2, aqua, etc.)

2. Enhanced model outputs/diagnostics for clouds and precip implemented in CMIP models (e.g. cfSites), including development of satellite simulator software (COSP).

3. Process understanding of clouds and their response to climate change, via observational analysis and modeling.

4. WCRP Clouds and Circulation grand challenge.5. Annual meeting for sharing new developments and ideas.

© Crown copyright Met Office

CFMIP Objectives

1: Inform improved assessments of cloud feedbacks on climate change by:a) improving our understanding of cloud-climate feedback

mechanisms. b) improving evaluation of clouds and cloud feedbacks in

climate models. 2: Coordinate understanding of other aspects of climate

response related to clouds, such as changes in circulation, regional-scale precipitation and non-linear change.

Our meeting agenda reflects the diversity of CFMIPToday:

1. Cloud feedbacks and emergent constraints2. Forcing, feedbacks, and climate sensitivity

Tuesday:3. Low cloud feedbacks and adjustments4. Precipitation and hydrological sensitivity5. Coupling of clouds with circulation

Wednesday:6. Convective organization and role of clouds in climate variability7. Observations and model evaluation for process-level understanding

of clouds 8. Extratropical cloud feedbacks and cloud-aerosol interactions

Thursday:9. Climate model development toward better representation of clouds 10. CFMIP experiments and CFMIP-related activities

CFMIP-affiliated coordinated projects

• CFMIP3 contribution to CMIP6 [Webb et al. 2017 GMD]• Other CFMIP-related MIPs, formal and less formal (PatternMIP,

NonlinMIP, TracMIP, RCEMIP, several other interesting proposals)• CFMIP Observation Simulator Package (COSP) (Bodas-Salcedo)• CFMIP-OBS datasets (Chepfer)• CFMIP Diagnostic Codes Catalogue (Tsushima)• WCRP Cloud-Circulation Grand Challenge (Stevens/Bony)• WCRP climate sensitivity assessment (Sherwood/Webb)

• CMIP ‘DECK’ + CMIP6 Historical Experiments - AMIP, preindustrial control, 1% CO2, abrupt 4xCO2, CMIP6 Historical

• With CFMIP-recommended COSP + process diagnostics.

• CFMIP experiments in CMIP6

• Described in Webb et al. 2017 GMD paper

• Includes COSP + process diagnostics

• Modelling groups participate via CMIP6 activity on CMIP6 timescales (2016-2020)

• Hosted on the Earth System Grid as part of CMIP6 activity

• Required Tier 1 experiments and optional Tier 2 experiments

• Mark’s CFMIP-CMIP6 talk on Thursday will give you the details

Led by Mark Webb, CFMIP-proposed activities within CMIP6 will be the nucleus of CFMIP3

piControl 1pctCO2

Pre-industrial clouds and precipitation

Historical /present day clouds and precipitation

CO2 forcing, cloudand precipitationadjustments

Climate feedbacks and precipitation responses

abrupt-4xCO2CMIP6 historical

amip-4xCO2amip amip-p4K

aqua-control aqua-4xCO2

amip-future4K

abrupt-0p5xCO2

amip-piForcing

abrupt-solp4p

aqua-p4K

amip-lwoff amip-p4K-lwoff

aqua-control-lwoff

piSST-4xCO2-radpiSST

piSST-pxKa4SST

amip-m4K

a4SSTice-4xCO2

a4SSTice

amip-a4SST-4xCO2

piSST-4xCO2

abrupt-solm4p

CMIP/CMIP6

aqua-p4K-lwoff

CFMIP Tier 1

CFMIP Tier 2

abrupt-2xCO2

Clouds

Circulation and Precipitation

CFMIP CMIP6 Experiment Summary

CFMIP Observation Simulator Package (COSP)Bodas-Salcedo et al., BAMS, 2011

© Crown copyright

• COSP is used by all of the major CMIP modelling groups.

• CMIP6 version: COSP v1.4, available since Nov 2013, now on Github.

• Used in several posters and talks at this meeting.

https://www.earthsystemcog.org/projects/cfmip/

(Figures courtesy of K. Williams)

© Crown copyright Met Office

CFMIP Diagnostic Codes Catalogue

Any metrics/diagnostics related to clouds whose multi-model analysis results are published are welcome.

Modellers and analysts are encouraged to use and add to the Githubrepository – documentation and help/advice are available. For details see CFMIP website -> CFMIP Diagnostic Codes

or email yoko.tsushima@metoffice.gov.uk

[Tsushima et al. 2017 GMD]

CloudSat : Precipitation diagnostics (See Jen Kay’s talk on Tuesday), the corresponding observations => will be online by the end of the year

CALIPSO-GOCCP v.3.0 new variables : Opaque and Thin cloud Covers, Temperatures and Altitudes + Opaque cloud Altitude of full opacity Z_opaque (See Thibault Vaillant de Guelis’ poster)

=> Already available online

CALIPSO-GOCCP 10 years records: All variables from the CALIPSO-GOCCP 10-year record using CALIPSO Level1 v.4.10

=> will be available online this Fall

Ground-based observations : ReOBS datasetTen years records from European supersite, hourly multi-variables dataset+ COSP ground-based lidar simulato (See poster by Chiriaco et al. on Tuesday)

=> will be available online this Fall

CFMIP-OBS website update

http://climserv.ipsl.polytechnique.fr/cfmip-obs/

This is an exciting area for new discovery• Emergent constraints suggest new connections between

present observed cloud variability and future cloud feedbacks – but which ones to trust?

• Role of mixed-phase cloud microphysics in high-latitude cloud optical depth feedbacks stresses importance of observations.

• High-resolution regional and global models in real and idealized settings plausibly simulate cloud formation & organization processes over a broad range of climates.

• The interplay between clouds, radiation, precipitation, large-scale circulation, and surface state is the most interesting atmospheric dynamics problem of our time.

• A hierarchy of models and intercomparisons are producing illuminating results about what we do/don’t agree on.

* New approaches to studying cloud-aerosol-climate interaction

Thanks for coming and being a part of CFMIP!

• You are the future of CFMIP.• The talks and posters here light our collective road to a

future in which cloud feedbacks and cloud-circulation-precipitation interaction are no longer the problem children of climate modeling.