1. Proposed ASEP Modeling Proposal

2. October 1, 2005WAIS Meeting2 Why ASEP is Appealing to Modelers Great range of ice flow regimes. –Sheet flow interior –Streaming flow characterized by Unusually high velocities Hybrid Outlet glacier/Ice Stream –Ice streams are coupled to small ice shelves. Unique climate (very high accumulation). Oceans and thinning rates. Unknown past Emergence of high quality data

3. October 1, 2005WAIS Meeting3 Ice Sheet Modeling Status? Ice Sheet Models Ice Stream Model Ice Shelf Model Grounded Ice Model Basal Processes Climate Models Ocean Models Grounding Line Treatments Higher Order Shallow Ice Data

4. October 1, 2005WAIS Meeting4 What is Lacking? Connectivity –The components need to share information –This is an extremely challenging problem Accessibility –Can’t just get these things off the web. –Even if you could, would it make any sense? –Can we do better? –Would that be helpful?

5. October 1, 2005WAIS Meeting5 Connectivity: “ ” Attributes of –Transfer data Handle variety of data models Accommodate different numerical methods Rapid integration of new field data. –Reconcile different scales Temporal Spatial –Bi-directional in such a way that Convergence is reached Moments are upheld (conservation of mass, momentum, energy) –Perhaps a name; “Multi-physics coupling and model nesting”

6. October 1, 2005WAIS Meeting6 What can be Learned from the Open Source Movement Open development model –Many eyes catch bugs faster –Stability and correctness increase quickly Rate of change and development in software increases –New features – Innovation Accessibility solid Excellent suit of software development tools

7. October 1, 2005WAIS Meeting7 Achieving Connectivity and Accessibility Begin from GLIMMER framework –Big head start Involve software engineers –They focus on what we’ve been bad at. –Documentation, usability, and maintainability Use open development model –Allow distributed, web based software development and distribution Identify areas for ice sheet model development –Reference implementations –EXTENSIBILITY!

8. October 1, 2005WAIS Meeting8 Begin from GLIMMER Ice Sheet Models Ice Stream Model Ice Shelf Model Grounded Ice Model Basal Processes Climate Models Ocean Models Grounding Line Treatments Higher Order Shallow Ice Data FORTRAN 90 NetCDF GENIE

9. October 1, 2005WAIS Meeting9 Software Engineering Foci Maintainability –Software that is easy to maintain stays in use. –Resolve logical inconsistencies in code base –Automated tools for code re-factoring. Improvements to data model –Rapid integration of new data –Establish foundation for parallism User Interface –Intuitive –Accommodating of range of skill levels/sophistication. Documentation –Complete, range of users (expert to novice) Extensibility –Clear reference implementations

10. October 1, 2005WAIS Meeting10 Deliverables Advancement of GLIMMER to include –Re-factoring code for maintainability –Comprehensive documentation –Robust connectivity HO ice sheet models via Pattyn’s contribution Earth Systems Modeling Framework –Reference implementations Higher-order Model Basal parameterization Others –Provide excellent reference point for inter- comparisons.

11. October 1, 2005WAIS Meeting11 Modeling Questions Related to ASEP Flow conditions at the divide Contrasting the impacts of basal conditions on Thwaites, Smith, and PIG –Role of sediments vs. high driving stresses vs bed geometry/roughness Interplay of drainage basins. –Under what conditions does Thwaites take that interior lobe of the PIG drainage Role of smaller ice shelves What is the role of ASEP in larger Earth systems models? –Ocean/Ice shelf coupling –Climate coupling

12. October 1, 2005WAIS Meeting12 Work Plan and Budget Guidelines Meetings or Workshops –Importance of face to face meetings –Strengthen international dimension Independent over sight board –Convening at key meetings. –Comprised of glaciologists and software engineers. Parallel proposal to the NERC from Tony Paine

13. October 1, 2005WAIS Meeting13 Achieving goals of the IPY Business as usual? –No Advancing science –Yes Unifying scientific communities –Modeling/modeling –Modeling/field researcher –Modeling/remote sensor Broad Impacts –“Enthusiast” level user interface –Very strong public outreach component