1. Arctic System Model Workshop Background and Objectives International Arctic Research Center Hosted by National Center for Atmospheric Research May 19-22, Boulder, CO

2. Background A wide variety of uncoupled and coupled modeling of the Arctic is ongoing in the community Coordination has the potential to advance the collective effort IARC has an interest in contributing to the coordination

3. Goals of an Arctic System Model To produce the best possible modeling system for the Arctic region -- to investigate Arctic climate variability and change -- to serve as a vehicle for improvements in global model simulations of the Arctic -- to synthesize and guide observations of the Arctic -- to advance assessments of impacts on ecosystems, humans and the global system [from M. Holland, D. Lawrence, D. Bromwich]

4. Workshop goal A report that presents a strategy and optimal way forward in modeling of the Arctic system -- a strategic and an implementation plan that will foster community “buy-in” and ultimately increase the resources available to enhance Arctic system modeling

5. Key questions for discussion Would Arctic system science benefit by an alignment of efforts toward a cohesive community arctic system model? If not a single community end-to-end coupled model, is a coordinated model portfolio a good way to proceed – perhaps with the same coupling and archiving protocols? Are there science questions not being addressed at present that can be addressed by either of the above frameworks? How could a community effort benefit model intercomparisons?

6. Deliverable: A workshop report that includes An assessment of what is already ongoing Alignment with global modeling activities

7. Deliverable: A workshop report that includes An assessment of what is already ongoing Alignment with global modeling activities Is a community effort the best path to an ASM? -- model selection vs. modularity -- coupling strategy and implementation

8. Deliverable: A workshop report that includes An assessment of what is already ongoing Alignment with global modeling activities Is a community effort the best path to an ASM? -- model selection vs. modularity -- coupling strategy and implementation Interactions with observational programs and systems Phased implementation -- target some early successes -- which components are best kept “off-line”?

9. Deliverable: A workshop report that includes An assessment of what is already ongoing Alignment with global modeling activities Is a community effort the best path to an ASM? -- model selection vs. modularity -- coupling strategy and implementation Interactions with observational programs and systems Phased implementation -- target some early successes -- which components are best kept “off-line”? Coordination mechanisms IARC’s role