Future Directions in Globally Coordinated Climate Change Research

Future Directions in Globally Coordinated Climate Change Research Primary Sources: IPCC Expert Meeting on New Scenarios + CMIP 5/CMIP 6/SSP Plans (Mt/Ag/En. Sc/En. St 404/504 - Global Change) Future Directions (for the AR 5)

Approaches to Scenario Development Previous (SRES) (Mt/Ag/En. Sc/En. St 404/504 - Global Change) Current (RCPs) Future Directions (for the AR 5)

Representative Concentration Pathways RCP 8. 5 • > 8. 5 W/m 2 in 2100 • rising RCP 6 • ~ 6 W/m 2 in 2100 • stabilization RCP 4. 5 • 4. 5 W/m 2 in 2100 • stabilization RCP 2. 6 • peak 3 W/m 2 before 2100 • decline after peak (Mt/Ag/En. Sc/En. St 404/504 - Global Change) Future Directions (for the AR 5)

(Now the previous plan) (Mt/Ag/En. Sc/En. St 404/504 - Global Change) Future Directions (for the AR 5)

(K. E. Taylor, 2009) (Mt/Ag/En. Sc/En. St 404/504 - Global Change) Future Directions (for the AR 5)

Coupled Model Intercomparison Project Phase 6 (CMIP 6): 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 CMIP 6 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 CMIP 6 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 CMIP 6 -Endorsed MIPs and the forcing datasets. This Special Issue will open 30 April 2015.

CMIP 6 Design: Scientific Focus • • The scientific backdrop for CMIP 6 is the six WCRP Grand Challenges, and an additional theme encapsulating questions related to biogeochemical forcings and feedbacks. 1. Clouds, Circulation and Climate Sensitivity 2. Changes in Cryosphere 3. Climate Extremes 4. Regional Climate Information 5. Regional Sea-level Rise 6. Water Availability BUT NOTE: These are under review and evolving! 7. Biogeochemical forcings and feedbacks (AIMES & WGCM) The specific experimental design is focused on three broad scientific questions: 1. How does the Earth System respond to forcing? 2. 3. 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?

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) i. AMIP simulation (~1979 - 2014) ii. Pre-industrial control simulation iii. 1%/yr CO 2 increase iv. Abrupt 4 x. CO 2 run CMIP 6 Historical Simulation (entry card for CMIP 6) v. Historical simulation using CMIP 6 forcings (1850 -2014) Note: The themes in the outer circle of the figure might be slightly revised at the end of the MIP endorsement process (DECK & CMIP 6 Historical Simulation to be run for each model configuration used in the subsequent CMIP 6 -Endorsed MIPs) With proto-DECK experiments (LMIP, OMIP etc. ) in CMIP 6 Tier 1

CMIP Continuity Note: The themes in the outer circle of the figure might be slightly revised at the end of the MIP endorsement process

Criteria for DECK and CMIP 6 Historical Simulation (DECK = Diagnosis, Evaluation, and Characterization of Klima) (1) What are the criteria for the DECK? The DECK experiments are chosen 1. to provide continuity across past and future phases of CMIP, 2. to evolve as little as possible over time, 3. to be well-established, 4. 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 1. to serve as a benchmark for CMIP 6 -Endorsed MIPs 2. to use the specific forcings consistent with Phase X of CMIP 3. to be decoupled from model development cycle if needed.

Scenario. MIP: 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, Aer. Chem. MIP, C 4 MIP IAV Community: ICONICS, TGICA

CMIP 6 Design

Scenario. MIP Objectives https: //www 2. cgd. ucar. edu/research/ mips/scenario-mip Define and recommend an experimental design for future scenarios to be run by climate models as part of CMIP 6 Also: Coordinate the provision of IAM scenario information to climate modeling groups Coordinate the production of climate model simulations and facilitate provision of output

Scenario. MIP Goals 1. Facilitating integrated research across climate science, IAM and IAV communities – Span wide forcing range and intermediate levels – Continuity with CMIP 5 – Include new forcing pathways of interest 2. Anchoring targeted experiments to answer questions about specific forcings – Include scenarios with forcings (land use, aerosols) useful to other MIPs

The Scenario Process: CMIP 6 and Scenario MIP RCPs CMIP 6 Scenarios CMIP 5 SSPs Pattern scaling CMIP 6 IAM scenarios O’Neill & Schweizer, 2011; based on Moss et al. (2010). IAM, IAV More IAM, studies IAV studies

Scenario. MIP design: Specific scenarios CMIP 5 RCP sims Infeasible SSP ref. scens. Tier 1 (H/M/L) Shared Socioeconomic Pathways Tier 2 (H/M/L) SSP 1 SSP 2 SSP 3 SSP 4 SSP 5 Sustainability Middle of the Road Regional Rivalry Inequality Fossil-fueled Development SRES Forcing level (W/m 2) 8. 5 Ensemble ~7 6. 0 4. 5 ~3. 7 2. 6 Long-term extensions Overshoot

Scenario. MIP design: Specific scenarios CMIP 5 RCP sims Infeasible SSP ref. scens. Tier 1 (H/M/L) Shared Socioeconomic Pathways Tier 2 (H/M/L) SSP 1 SSP 2 SSP 3 SSP 4 SSP 5 Sustainability Middle of the Road Regional Rivalry Inequality Fossil-fueled Development Forcing level (W/m 2) 8. 5 ~7 Ensemble 6. 0 4. 5 ~3. 7 2. 6 Long-term extensions Overshoot SRES

Future Directions in Globally Coordinated Climate Change Research END (Mt/Ag/En. Sc/En. St 404/504 - Global Change) Future Directions (for the AR 5)