Future Directions in Globally Coordinated Climate Change Research

1. Future Directions inGlobally Coordinated Climate Change Research Primary Sources: IPCC Expert Meeting on New Scenarios + CMIP5/CMIP6/SSP Plans

2. Approaches to Scenario Development Previous (SRES) Current (RCPs)

3. Representative Concentration Pathways RCP8.5 • > 8.5 W/m2 in 2100 • rising • RCP6 • ~ 6 W/m2 in 2100 • stabilization • RCP4.5 • 4.5 W/m2 in 2100 • stabilization • RCP2.6 • peak 3 W/m2 before 2100 • decline after peak

4. (Now the previous plan)

5. (K.E. Taylor, 2009)

6. (K.E. Taylor, 2009)

7. Coupled Model Intercomparison Project Phase 6 (CMIP6): Design and Organization Veronika Eyring, Jerry Meehl, Bjorn Stevens, Ron Stouffer, Karl Taylor (CMIP Panel) Sandrine Bony and Cath Senior (WGCM Co-chairs) V. Balaji (WGCM Infrastructure Panel co-chair with K. Taylor) 16 January 2015 (updates to CMIP6 Data Request Timeline on Slide 9) Please see the CMIP Panel website for additional information and updates: http://www.wcrp-climate.org/index.php/wgcm-cmip/about-cmip Contact for questions: CMIP Panel Chair Veronika Eyring (email: Veronika.Eyring@dlr.de) The final CMIP6 Design, possibly with small modifications to the here presented figures and wording, will be published in a GMD Special Issue together with a description of the CMIP6-Endorsed MIPs and the forcing datasets. This Special Issue will open 30 April 2015.

8. CMIP6 Design: Scientific Focus • The scientific backdrop for CMIP6 is the six WCRP Grand Challenges, and an additional theme encapsulating questions related to biogeochemical forcings and feedbacks. • Clouds, Circulation and Climate Sensitivity • Changes in Cryosphere • Climate Extremes • Regional Climate Information • Regional Sea-level Rise • Water Availability • Biogeochemical forcings and feedbacks (AIMES & WGCM) • The specific experimental design is focused on three broad scientific 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 climate variability, predictability and uncertainties in scenarios? BUT NOTE: These are under review and evolving!

9. WCRP Grand Challenges: (1) Clouds, circulation and climate sensitivity, (2) Changes in cryosphere, (3) Climate extremes, (4) Regional climate information, (5) Regional sea-level rise, and (6) Water availability, plus an additional theme on “Biogeochemical forcings and feedbacks” DECK (entry card for CMIP) AMIP simulation (~1979- 2014) Pre-industrial control simulation 1%/yr CO2 increase Abrupt 4xCO2 run CMIP6 Historical Simulation (entry card for CMIP6) Historical simulation using CMIP6 forcings (1850-2014) (DECK & CMIP6 Historical Simulation to be run for each model configuration used in the subsequent CMIP6-Endorsed MIPs) With proto-DECK experiments (LMIP,OMIP etc.) in CMIP6 Tier1 Note: The themes in the outer circle of the figure might be slightly revised at the end of the MIP endorsement process

10. CMIPContinuity Note: The themes intheoutercircle ofthefigure mightbe slightly revised attheendoftheMIPendorsement process

11. CriteriaforDECKandCMIP6HistoricalSimulation (DECK = Diagnosis, Evaluation, and Characterization of Klima) (1) What are the criteria for the DECK? The DECK experiments are chosen to provide continuity across past and future phases of CMIP, to evolve as little as possible over time, to be well-established, to be part of the model development cycle. (2) What are the criteria for the CMIP Phase X Historical Simulation? The CMIP Phase X Historical Simulation is chosen to serve as a benchmark for CMIP6-Endorsed MIPs to use the specific forcings consistent with Phase X of CMIP to be decoupled from model development cycle if needed.

12. ScenarioMIP: Current Status Brian O’Neill, NCAR Scenario MIP Co-chairs: Brian O’Neill, Claudia Tebaldi, Detlef van Vuuren Members: Pierre Friedlingstein, George Hurtt, Reto Knutti, Jean-Francois Lamarque, Jason Lowe, Jerry Meehl, Richard Moss, Ben Sanderson Contributions/feedback from additional IAM researchers:Kate Calvin, Shinichiro Fujimori, Elmar Kriegler, Keywan Riahi Other MIPs: esp. LUMIP, AerChemMIP, C4MIP IAV Community: ICONICS, TGICA

13. CMIP6 Design

14. ScenarioMIP Objectiveshttps://www2.cgd.ucar.edu/research/mips/scenario-mip Define and recommend an experimental designfor future scenarios to be run by climate models as part of CMIP6 Also: Coordinate the provision of IAM scenario information to climate modeling groups Coordinate the production of climate model simulations and facilitate provision of output

15. ScenarioMIP Goals • Facilitating integrated research across climate science, IAM and IAV communities • Span wide forcing range and intermediate levels • Continuity with CMIP5 • Include new forcing pathways of interest • Anchoring targeted experiments to answer questions about specific forcings • Include scenarios with forcings (land use, aerosols) useful to other MIPs

16. The Scenario Process:CMIP6 and Scenario MIP RCPs CMIP6 Scenarios SSPs CMIP5 Patternscaling CMIP6 IAMscenarios IAM, IAV studies More IAM, IAV studies O’Neill & Schweizer, 2011; based on Moss et al. (2010).

17. ScenarioMIP design: Specific scenarios CMIP5 RCP sims Infeasible SSP ref. scens. Shared Socioeconomic Pathways Tier 1 (H/M/L) SSP1Sustainability SSP2Middle oftheRoad SSP3RegionalRivalry SSP4Inequality SSP5Fossil-fueledDevelopment Tier 2 (H/M/L) SRES 8.5 6.0 Forcing level (W/m2) Ensemble ~7 4.5 2.6 ~3.7 Long-term extensions Overshoot

18. ScenarioMIP design: Specific scenarios CMIP5 RCP sims Infeasible SSP ref. scens. Shared Socioeconomic Pathways Tier 1 (H/M/L) SSP1Sustainability SSP2Middle oftheRoad SSP3RegionalRivalry SSP4Inequality SSP5Fossil-fueledDevelopment Tier 2 (H/M/L) SRES 8.5 6.0 Forcing level (W/m2) Ensemble ~7 4.5 2.6 ~3.7 Long-term extensions Overshoot

19. END Future Directions inGlobally Coordinated Climate Change Research