International C20C Project: History and Overview J. Kinter, C. Folland and F. Molteni Third International C20C Workshop 19 April 2004  ICTP - Trieste, Italy

Center for Ocean- Land-Atmosphere Studies Background Purpose: Characterize variability and predictability of climatic conditions and events of the past ~130 years associated with various slowly varying forcing functions Purpose: Characterize variability and predictability of climatic conditions and events of the past ~130 years associated with various slowly varying forcing functions Initially focused on AGCMs forced with HadISST sea surface temperature and sea ice analysis Initially focused on AGCMs forced with HadISST sea surface temperature and sea ice analysis

Excerpt from Schubert et al (Science, 19Mar2004) Example:

Center for Ocean- Land-Atmosphere Studies Background (continued) Period of interest: 1871-current Period of interest: 1871-current Organization: Organization: Jointly organized by Hadley Centre, UK & Center for Ocean- Land-Atmosphere Studies (COLA), USA Jointly organized by Hadley Centre, UK & Center for Ocean- Land-Atmosphere Studies (COLA), USA 15 different modeling groups participating internationally 15 different modeling groups participating internationally CLIVAR project & reporting to WMO/CAS/WGNE CLIVAR project & reporting to WMO/CAS/WGNE Now includes many other forcing data sets, including greenhouse gases, ozone, volcanic aerosols and solar variability Now includes many other forcing data sets, including greenhouse gases, ozone, volcanic aerosols and solar variability Being expanded to include use of coupled models in order to more accurately simulate modes of variability that are inherently coupled Being expanded to include use of coupled models in order to more accurately simulate modes of variability that are inherently coupled

Center for Ocean- Land-Atmosphere Studies Current Participating Groups Bureau of Meteorology, Australia () Bureau of Meteorology, Australia ( ) China Meteorological Agency, China () China Meteorological Agency, China ( ) Center for Ocean-Land-Atmosphere Studies, USA () Center for Ocean-Land-Atmosphere Studies, USA ( ) Centro de Previsão de Tempo e Estudos Climáticos, Brazil () Centro de Previsão de Tempo e Estudos Climáticos, Brazil ( ) Department of Natural Resources, Mines & Energy, Queensland, Australia () Department of Natural Resources, Mines & Energy, Queensland, Australia ( ) NASA Goddard Space Flight Center, USA () NASA Goddard Space Flight Center, USA ( gmao.gsfc.nasa.gov ) Hadley Centre, Met Office, UK () Hadley Centre, Met Office, UK ( ) International Centre for Theoretical Physics, Italy () International Centre for Theoretical Physics, Italy ( ) MeteoFrance, France () MeteoFrance, France ( ) Main Geophysical Observatory, Russia () Main Geophysical Observatory, Russia ( ) Meteorological Research Institute, Japan () Meteorological Research Institute, Japan ( ) National Institute for Environmental Studies, Japan () National Institute for Environmental Studies, Japan ( ) National Institute of Water and Atmospheric Research, New Zealand () National Institute of Water and Atmospheric Research, New Zealand ( ) Seoul National University, Korea () Seoul National University, Korea ( ) University of California at Los Angeles, USA () University of California at Los Angeles, USA ( )

Center for Ocean- Land-Atmosphere Studies Chronology Project initiated by Hadley Centre Project initiated by Hadley Centre several informal bilateral collaborations established several informal bilateral collaborations established 1 st workshop held at Hadley Centre in Nov st workshop held at Hadley Centre in Nov 1994 Input to 1995 IPCC assessment and special session at 1 st international AMIP conference in 1995 Input to 1995 IPCC assessment and special session at 1 st international AMIP conference in 1995 Revitalized by Hadley Centre and COLA Revitalized by Hadley Centre and COLA 1998 invitation to several modeling groups 1998 invitation to several modeling groups infrastructure provided by COLA ( GDS) infrastructure provided by COLA ( GDS) 2 nd workshop held at COLA in Jan 2002 (reported in CLIVAR Exchanges, Jun 2002) 2 nd workshop held at COLA in Jan 2002 (reported in CLIVAR Exchanges, Jun 2002) Agreed set of runs with updated forcing data sets, diagnostics and special projects Agreed set of runs with updated forcing data sets, diagnostics and special projects C20C established as official CLIVAR project in 2003 C20C established as official CLIVAR project in 2003 Third Workshop Apr 2004, ICTP, Italy Third Workshop Apr 2004, ICTP, Italy

Center for Ocean- Land-Atmosphere Studies Contributions C20C contributes to: Seasonal to interannual predictability Seasonal to interannual predictability Decadal to interdecadal variability & predictability Decadal to interdecadal variability & predictability Simulations of climate trends Simulations of climate trends Model evaluation Model evaluation

Center for Ocean- Land-Atmosphere Studies Special Topics Predictability of seasonal to decadal phenomena Predictability of seasonal to decadal phenomena 1930s drought in USA (“Dust Bowl”) 1930s drought in USA (“Dust Bowl”) European winter European winter Autumn 2000 western European floods Autumn 2000 western European floods 2003 European heat wave 2003 European heat wave Decadal modulation of response to ENSO in Australia, Indian monsoon Decadal modulation of response to ENSO in Australia, Indian monsoon Time series and trends Time series and trends SOI, NAO, PNA, Asian monsoon rainfall, Sahel rainfall, Nordeste Brazil rainfall, MJO trends SOI, NAO, PNA, Asian monsoon rainfall, Sahel rainfall, Nordeste Brazil rainfall, MJO trends Global and regional land surface air temperature trends Global and regional land surface air temperature trends Others, e.g., river runoff trends Others, e.g., river runoff trends

Center for Ocean- Land-Atmosphere Studies Validating Data Sets NCEP/NCAR Reanalysis ( ) NCEP/NCAR Reanalysis ( ) ERA40 Reanalysis ( ) ERA40 Reanalysis ( ) HadSLP global sea level pressure analysis ( ) HadSLP global sea level pressure analysis ( ) Jones land surface air temperature and Hulme land surface rainfall analyses ( ) Jones land surface air temperature and Hulme land surface rainfall analyses ( ) Xie-Arkin global precipitation analysis ( ) Xie-Arkin global precipitation analysis ( )

Center for Ocean- Land-Atmosphere Studies Diagnostics Monthly means, all ensemble members Monthly means, all ensemble members Geopotential height at 500 and 200 hPa Geopotential height at 500 and 200 hPa Mean sea level pressure Mean sea level pressure Precipitation and evaporation Precipitation and evaporation Temperature at 2m and 850 hPa Temperature at 2m and 850 hPa Zonal and meridional winds at 850 and 200 hPa Zonal and meridional winds at 850 and 200 hPa Total heat flux and wind stress Total heat flux and wind stress Soil moisture index Soil moisture index Zonal mean cross-sections of U, V, T and q Zonal mean cross-sections of U, V, T and q Basic statistics Basic statistics Seasonal means and standard deviations Seasonal means and standard deviations Estimates of forced variability (ANOVA) Estimates of forced variability (ANOVA) Linear regression trends (or ) Linear regression trends (or ) Regression with NINO3.4 Regression with NINO3.4 Special diagnostic projects Special diagnostic projects {Refer to Second C20C Workshop, Working Group 2 Report} {Refer to Second C20C Workshop, Working Group 2 Report}

Center for Ocean- Land-Atmosphere Studies Links to CLIVAR C20C became a CLIVAR activity in 2003 C20C became a CLIVAR activity in 2003 Also reports to Working Group on Numerical Experimentation (WCRP/CAS/WGNE) Also reports to Working Group on Numerical Experimentation (WCRP/CAS/WGNE) Exploring links to WCRP Working Groups on Seasonal to Interannual Prediction (WCRP/CLIVAR/WGSIP) and Coupled Modeling (WCRP/CAS/WGCM) Exploring links to WCRP Working Groups on Seasonal to Interannual Prediction (WCRP/CLIVAR/WGSIP) and Coupled Modeling (WCRP/CAS/WGCM)

Center for Ocean- Land-Atmosphere Studies C20C Phases of Activity Phase 1 (prior to 2003) : SST and sea ice Phase 1 (prior to 2003) : SST and sea ice Hadley Centre provides HadISST1.1 SST and sea ice data set as lower boundary conditions Hadley Centre provides HadISST1.1 SST and sea ice data set as lower boundary conditions Integrate over (at least ) Integrate over (at least ) Ensembles of at least 4 members Ensembles of at least 4 members Phase 2 ( ) : atmospheric composition Phase 2 ( ) : atmospheric composition Greenhouse gases – CO 2, O 3, etc. Greenhouse gases – CO 2, O 3, etc. Aerosols (volcanic) Aerosols (volcanic) Solar variability Solar variability Phase 3 ( ) : land surface variability Phase 3 ( ) : land surface variability specified evolution of soil wetness and vegetation specified evolution of soil wetness and vegetation

Center for Ocean- Land-Atmosphere Studies Current Activities Third Workshop Third Workshop April 2004; hosted by ICTP (Trieste, Italy) April 2004; hosted by ICTP (Trieste, Italy) Results of Phase 1 integrations; initial Phase 2 results Results of Phase 1 integrations; initial Phase 2 results Planning for Phase 2 and beyond Planning for Phase 2 and beyond Representatives of WCRP programs – discussion of how to specify/deal with forcings, coupled models Representatives of WCRP programs – discussion of how to specify/deal with forcings, coupled models Planning for comparison to coupled models Planning for comparison to coupled models Coupling to mixed layer or dynamical ocean Coupling to mixed layer or dynamical ocean Coordination with WGCM Coordination with WGCM Efficient estimation of anthropogenic signals Efficient estimation of anthropogenic signals

Center for Ocean- Land-Atmosphere Studies Issues What are the limitations of AGCM runs that have no direct coupling to the ocean surface? Are local/regional fluxes misleading? What are the limitations of AGCM runs that have no direct coupling to the ocean surface? Are local/regional fluxes misleading? How should we include coupled models in C20C work, e.g. thermohaline-forced variations in climate? understanding interannual predictability? How should we include coupled models in C20C work, e.g. thermohaline-forced variations in climate? understanding interannual predictability? Should we adopt a set of common or core diagnostics that all groups will produce in order to contribute to the IPCC assessment (model evaluation) in a more systematic way? Should we adopt a set of common or core diagnostics that all groups will produce in order to contribute to the IPCC assessment (model evaluation) in a more systematic way?

Center for Ocean- Land-Atmosphere Studies Future … Report of Third Workshop to CLIVAR 2004 Conference in June 2004 Report of Third Workshop to CLIVAR 2004 Conference in June 2004 Input to model evaluation or other relevant sections of 2005 IPCC assessment Input to model evaluation or other relevant sections of 2005 IPCC assessment Fourth C20C Workshop in 2006 tentatively being planned for Exeter, UK Fourth C20C Workshop in 2006 tentatively being planned for Exeter, UK