Action items inspired by the IPCC exercise

The Working Group on Coupled ModelingKarl E. Taylor

Program for Climate Model Diagnosis and Intercomparison (PCMDI)

with credit and thanks to Sandrine Bony

Presented to the Fourth WCRP Observation and Assimilation Panel Meeting

Hamburg, Germany29 March 20104th WOAP Meeting29 March 2010K. E. Taylor 1Who are the WGCM?MembersSandrine Bony (co-chair)Gerald Meehl (co-chair)Veronica EyringMarco GiorgettaDavid KarolyM. KimotoCorinne Le QurNatalie MahowaldCatherine SeniorBin WangEx-Officio MembersGokhan DanabasogluHelge DrangeGreg FlatoFilippo GiorgiJohn MitchellRonald StoufferKarl Taylor

PCMDI4th WOAP Meeting29 March 2010K. E. Taylor What is the WGCMs mission?Foster the development of coupled climate models (and now ESMs)Coordinate model experiments and inter-comparisons to:better understand natural climate variabilitypredict the climate response to natural & anthropogenic perturbationsPromote and facilitate model evaluation and diagnosis of shortcomings

A balance among:Predicting Evaluating - UnderstandingPCMDI4th WOAP Meeting29 March 2010K. E. Taylor Major challengesHow can we improve our confidence in climate models?How can we assess the credibility of model projections ?

PCMDI4th WOAP Meeting29 March 2010K. E. Taylor

LES modelsCloud Resolving Models

Single ColumnModels3D-Climate ModelsNWP Models

High resolution global models(global CRM, MMF)

Global observational datasetsField campaigns & instrumented sites

How can we gauge and gain confidence in GCMs projections?(1) Bottom-Up approach : evaluate and improve the physical basis of climate models through large-scale and process-scale evaluations

Analysis & Understandingclimate changeModel projections

4th WOAP Meeting29 March 2010K. E. Taylor 5

LES modelsCloud Resolving Models

Single ColumnModels3D-Climate ModelsNWP Models

High resolution global models(global CRM, MMF)

Global observational datasetsField campaigns & instrumented sites

How can we gauge and gain confidence in GCMs projections?(1) Bottom-Up approach : evaluate and improve the physical basis of climate models through large-scale and process-scale evaluations

(2) Top-Down approach : understand the models' results & identify critical processes to provide guidance for specific observational tests/process studies and model improvements

Analysis & Understandingclimate changeModel projections

4th WOAP Meeting29 March 2010K. E. Taylor 6The second approach has traditionally dominated WGCMs interests, but this is changing.Current activities focus on understanding why model projections differe.g., quantifying the strength of individual feedbacks across models. Evaluate climate models over a wide range of scales and phenomenaFrom weather to paleoFrom global to regionalFrom individual physical processes to climate (across all physical and biogeochemical components)Explore how model formulation and present-day model performance translate to reliability of climate projectionsPerhaps the biggest challenge of all.

PCMDI4th WOAP Meeting29 March 2010K. E. Taylor CMIP3 transformed climate science by enabling community-wide participation in the analysis of model output. 35 Tbytes of model output stored at PCMDI

More than 765 TB downloaded

More than 3,000 users

More than 550 publications

Aug 2009Jan 2007(AR4 WGI)Nov 2004Courtesy of Bob Drach (PCMDI)PCMDI4th WOAP Meeting29 March 2010K. E. Taylor What are prospect for CMIP5?Better understand robust and uncertain aspects of climate change Enable quantification of strengths of major feedbacksInclude carbon cycle component (ESMs)Better meet the needs of the impacts communityA more comprehensive set of model outputProvide information needed to assess adaptation and mitigation strategiesCoordinate/integrate across the modeling community:CMIP includes portions of: C4MIP, PMIP, AMIP, CFMIP, Aqua-planet

PCMDI4th WOAP Meeting29 March 2010K. E. Taylor CMIP5: Three Suites of ExperimentsLong-Term(century & longer)TIER 1TIER 2COREevaluation& projectiondiagnosisNear-Term(decadal prediction)(initialized ocean state)hindcasts & forecastsCORETIER 1TIER 2TIER 1AMIPtime-sliceCOREAtmosphere-Only(for computationally demanding and NWP models)TIER 1TIER 2Taylor et al. 2008, http://cmip-pcmdi.llnl.gov/cmip54th WOAP Meeting29 March 2010K. E. Taylor Example: CMIP5 long-term suite of experimentsAn important focus is model evaluation and understanding...D & A ensemblesControl, AMIP, & 20 CRCP4.5, RCP8.5natural-only, GHG-only individual forcingRCP2.X, RCP6 extend RCP4.5 to 2300 extend RCP8.5 & RCP2.X to 2300 ensemble of abrupt 4xCO2 5-yr runsaqua planet (clouds) uniform SST (clouds) Mid-Holocene & LGMlast millennium E-driven RCP8.5E-driven control & 20 Cpatterned SST (clouds) aerosol forcing ca. 2000AC&C4 (chemistry)1%/yr CO2 (140 yrs)abrupt 4XCO2 (150 yrs)fixed SST with 1x & 4xCO2radiation code sees 1xCO2 (1%/yr or 20C+RCP4.5)carbon cycle sees 1XCO2 (1%/yr or 20C+RCP4.5)UnderstandingModel EvaluationClimateProjectionsGreen subset is for coupled carbon-cycle climate models onlyensembles: AMIP & 20 C4th WOAP Meeting29 March 2010K. E. Taylor 11CMIP now involves many WCRP/IGBP partnersExample: CMIP5 long-term suite of experiments

Detection-Attribution(IDAG)Paleo(PMIP, IGBP-PAGES)Cloud andmoist processes(CFMIP-GCSSWGNE)Carbon-climate feedbacks(C4MIP, IGBP-AIMES)Integrated AssessmentConsortium (IAM),connection to WG-III+ Satellite simulators& process diagnostics (CFMIP-GCSS)Chemistry, aerosols(SPARC, AC&C, CCMVal, aerocom)4th WOAP Meeting29 March 2010K. E. Taylor 12WGCM (with others) promotes a variety of community-wide activities to advance climate modelingMentioned already:SPARC & IGBP/IGAC (CCMVal, AeroCom..): chemistry & aerosolsWGCM & IGBP/PAGES (PMIP): paleoclimateWGCM, GCSS, and WGNE (CFMIP): clouds and cloud feedbacksWGCM, IGBP/AIMES (C4MIP): carbon cycleIDAG: detection and attribution studiesWGNE/WGCM (Transpose-AMIP): evaluation of climate models in NWP modeCLIVAR WGSIP, WGOMD : seasonal to interannual prediction, oceanTFRCD (CORDEX) : regionalGEWEX GCSS (GPCI) : processesWGNE/WGCM Metrics panel CF metadata conventions for archiving and sharing climate dataWGCM endorsed demonstration study (GeoMIP): geo-engineering PCMDI4th WOAP Meeting29 March 2010K. E. Taylor WGCMs Challenge to WOAPPush to make observations as easily available and useable as climate model output generated by CMIP.Provide easy access and guidance on quality and limitationsFollowing CMIP3, store observational data in a standard way and make it available through a common portal.The WGCM has endorsed a NASA/JPL pilot initiative to provide satellite data in a form useful to CMIP5 (Joao Texeira, Duane Waliser, Jerry Potter, S Boland).A similar NOAA initiative may be launched soon, and this in the work plans ISENES (a European project to provide infrastructure support for climate model research)These new projects were all partially inspired by CMIPThe WGCM would like to see similar efforts undertaken by other providers of satellite and in-situ observations. PCMDI4th WOAP Meeting29 March 2010K. E. Taylor WGCMs Challenge to WOAPProvide encouragement and possibly a framework whereby the observational and climate modeling community would interact to identify observational data sets useful in model evaluationThe highest priority would be to consider the CMIP output - variables, temporal/spatial sampling, time-periods.Establish guidelines forMetadata that will facilitate search and discovery.Formats and metadata that will facilitate analysis (as provided by the CF metadata standard)Develop a strategy for making multiple datasets developed for this purpose accessible in a way that parallels the CMIP model output archive. PCMDI4th WOAP Meeting29 March 2010K. E. Taylor PCMDI4th WOAP Meeting29 March 2010K. E. Taylor List of CMIP5 output fieldshttp://cmip-pcmdi.llnl.gov/cmip5/output_req.htmlDomains:Atmosphere (including aerosols)Ocean (including carbon cycle variables)Land surface (including carbon cycle variables)CryosphereTemporal samplingAnnualMonthlyDaily (including max., min. & mean surf. Air T, precip. humidity, surf. wind, PSL; many more 2-d & 3-d fields for 1950-2005)6-hourly3-hourly (including from 1950-2005)~ half-hour (but not globally)

PCMDI4th WOAP Meeting29 March 2010K. E. Taylor Model output characteristicsSpecified template for filenames and directory structureAdditional metadatamodeling_realmtracking_idmodel_idcreation_dateForcinginitialization_method,physics_versionOutput may be on native grid, rather than longitude-latitude cartesian

PCMDI4th WOAP Meeting29 March 2010K. E. Taylor CMIP5 Decadal Prediction Experimentsadditional predictions Initialized in 01, 02, 03 09100-yr control & 1% CO2prediction with 2010 Pinatubo-like eruptionalternative initialization strategies atmos. chemistry &/or aerosols &/or regional air quality AMIPincrease ensemble sizes from O(3) to O(10) members hindcasts without volcanoes30-year hindcast and prediction ensembles: initialized 1960, 1980 & 2005 10-year hindcast & prediction ensembles: initialized 1960, 1965, , 20054th WOAP Meeting29 March 2010K. E. Taylor CMIP5 Atmosphere-Only Experiments(targeted for computationally demanding and NWP models)AMIP(1979-2008)AMIP ensembleAMIP SSTs with 4XCO2aqua planet (clouds)uniform SST (clouds) patterned SST (clouds)future time-slice(2026-2035)Future time-slice ensemble4th WOAP Meeting29 March 2010K. E. Taylor 20