Consortium October 6, 2016

1. Consortium October 6, 2016

2. Air Stagnation Advisory Criterion Graphics • Create products based on NWS criteria for Air Stagnation Advisories • Different offices have different criteria

7. Info Web Page: http://www.atmos.washington.edu/mm5rt/airstagnation/ • Rob and Jacob have decided they like the f3d graphic (3.6) in the Nov 27-Nov 30 case and 3.4 in the Dec 31-Jan 6 case. Dave is aslo going to produce the duration-dependent graphic (since that's what actually meets the full air stagnation advisory criteria for the NWS).

8. One the fly meteograms, time heights and soundings are fixed • Can choose any location you want.

9. On the fly 4/3 km graphics generator • http://www.atmos.washington.edu/mm5rt/on_the_fly_plots/ • For use off-campus, you need to login with User: trajectory Password: 7rajectory1

10. Mt. Rainier 24-h Precip Example

11. Trajectories: - all trajectories are now displaying terrain height and trajectory height - improved run speed (saved 45 minutes)

13. Evaluation of WRF 3.8.1 (we are using 3.7.1)Wind a bit worse

17. Bottom Line: 8.1 does not produce better verification than 7.1. Maybe worse. At this point, no reason to switch

18. Additional Computer Resources • New, higher speed infiniband switch (56 gbits per second between nodes) • Added 8 nodes of 24 cores each. • Total of 432 cores (processors) on SAGE • We have been testing the new nodes and have been having problems (sudden failures), odd changes in performance with different numbers of cores. • We now believe we have a hardware problem.

19. New Domain • Have been testing domain, but the sudden failures have slowed us down. • Hopefully, with new memory card, can move forward next week.

27. Timing (suspect because bad memory) • Using 408 out of 432 cores, the new domain rain 30 minutes slower than current domain • Will rerun timing tests after memory fixed and attempt to use more cores (may have to make slight changes in domain) • Other things to try (nestdown approach with ONLY running 4/3 km domain) • Split domain

28. 6-month Strategic Plan • October: • figure out the problems with the new cluster • Try alternative approaches if necessary to resolve problems and to speed up. • Reduce number of nests (12-4-1.3 km) • Nestdown 1.3 km from 4 km saved every ten minutes. • November • Test new physics (MYNN PBL-–same as used in HRRR), new Morrison P3 microphysics scheme (cheaper and better) • December • Upgrade physics if beneficial • January • Evaluate computer resources and approaches for a 4-km ensemble of the region, using IC and physics uncertainty--could do in off hours. • Feb-March • Start constructing ensemble.

29. A Northwest Consortium for Regional Climate Modelling Cliff Mass Department of Atmospheric Sciences University of Washington

30. Society needs reliable information on the regional implications of climate change • Infrastructure decisions are being made now for assets that will last well into the current century when the impact of GW will be substantial • Adaptation planning • Motivation for mitigation efforts

31. Bottom Line of the Talk There is only one viable method for producing the required regional climate predictions: dynamical downscaling of global climate models But to do this right, there is much that is required.

32. Requirements • The use of large numbers of global model simulations (GCMs) to explore initial condition, model, and physics uncertainty. • Filtering to remove GCMs unable to simulate realistically the current climate • Use of sufficient resolution in the regional climate models (minimum 12-15 km grid spacing) to get realistic NW circulations • Use of an appropriate nested domain structure of the regional simulations (MUST include the Rockies with sufficient resolution) • Must have sophisticated post-processing to reduce biases and get reliable probabilities.

33. The Challenge: Can We Do This Right, Together? • Combine regional resources and personnel so that together we can do what one group cannot accomplish alone. • There is a precedent for such combination of resources: the Northwest Modeling Consortium.

34. Many of the technical issues are very similar….

35. Dynamical Downscaling Not Statistical Downscaling • Only fully dynamical downscaling can hope to simulate the non-linearities and complexities of the future climate response. • Examples: • Location and distribution of precipitation changes as stability changes. • Onshore flow and coastal marine clouds enhanced by greater onshore pressure gradients • Albedo feedbacks as snow melts.

36. Echam-5 versus WRF

38. Dozens of downscaled GCM runs not 1-3 • There is substantial uncertainty in the GCM simulations and a handful of simulations can not get a handle on the inherent uncertainties. • Sources: physics uncertainty, initial state uncertainty, emission uncertainty, and many more. • GCMs produce a wide variety of local solutions

40. Over the Northwest, the simulations must have a grid spacing of a least 12-15 km grid spacingBased on over 10 years of twice-daily simulations at 36-12-4-1.3 km at the University of Washington, with objective verification

42. 150 km versus 12 km

43. Integration of ancillary physics/applications (e.g, hydro, coastal ocean, air quality) to create a total environmental modeling system

45. The Northwest Climate Modeling Consortium: A Proposal • Combine resources of regional government entities, state and Federal agencies, foundations, academic institutions, tribes, and other to create the most robust climate predictions possible. • Similar to the NW modeling consortium, decisions could be make by contributing stakeholders • Amazon has provided a modest amount to start this.

46. Tasks • Acquire or secure sufficient computer resources for regional climate downscaling and to run additional GCM simulations. • Develop GCM filtering approaches. • Acquire CMIP-5 (6) GCM runs and run/acquire additional simulations. • Run large numbers of regional climate simulations

48. Tasks • Run applications models (e.g., hydro) • Optimally post-process and combine regional climate simulations to provide robust probabilistic guidance

49. Products • Model grids and custom products will be available to supporting stakeholders and their designees. • Grids can also be made available to regional climate impacts group (Oregon State, UW CIG, etc.)

50. The END