NMME Sub-seasonal Forecast System Exploratory Workshop

March 30-31, 2015

NCWCP Conference Center
5830 University Research Court
College Park, Maryland

Prospectus || Participants
Agenda (pdf)

Monday, March 30 (all times are Eastern Time)

8:00 - 8:15 Coffee/refreshments
8:15 - 8:30 Welcome & Workshop Scope (Jin Huang and Annarita Mariotti)

Session 1: Overview & Motivation
(Chair: Jin Huang)

8:30 - 9:00 Overview of Challenges in Subseasonal Prediction (Frederic Vitart)
9:00 - 9:20 Overview of NMME Project and Subseasonal Experiment - Part 1 (Ben Kirtman), Part 2 (Kathy Pegion)
9:20 - 9:40 Bridging the Gap Between Forecast and Action (John Dutton)

Session 2: Sources and limits of subseasonal predictability
(Chair: Dan Eleuterio)

9:40 - 9:55 Land-Atmosphere Interactions (Randy Koster)
9:55 - 10:10 Ocean-Atmosphere Interactions (Eric Chassignet)
10:10 - 10:25 Predictability of Tropical Subseasonal Variability (Duane Waliser – remotely)

10:25 - 10:45 Coffee Break

10:45 - 11:00 NAO prediction and the stratosphere (Adam Scaife - remotely)
11:00 - 11:15 MJO-NAO connection and its impact on subseasonal prediction (Hai Lin)
11:15 - 11:30 Linking stratospheric predictability to prediction (Ming Cai)
11:30 - 11:45 Blocking (Stan Benjamin)
11:45 - 12:00 Extremes (Scott Weaver)

12:00 - 10:00 Lunch

Session 3: Existing Modeling Systems (experimental or operational) sub-seasonal prediction skills (Chair: Annarita Mariotti)

Each presentation should include:

  • prediction system components
  • system design (e.g., initialization, reforecast frequency, ensemble size) including requirements and computational aspects
  • current or planned prediction products including skill assessment
  • requirements for future development
  • readiness of hindcasts for research

1:00 - 1:15 CFSv2 data for week 3 and week 4 (Huug van den Dool)
1:15 - 1:30 ECMWF (Frederic Vitart)
1:30 - 1:45 UK Met Office (Anca Brookshaw)
1:45 - 2:00 Environment Canada (Bertrand Denis)
2:00 - 2:15 Navy (Tim Whitcomb)
2:15 - 2:30 NCAR (Ben Kirtman)
2:30 - 2:45 NASA (Randy Koster)
2:45 - 3:00 ESRL (Shan Sun)
3:00 - 3:15 GFDL (Xiaosong Yang)
3:15 - 3:30 APCC (Haejeong Kim)

3:30 - 3:45 Coffee Break

Session 4: Breakout Session: Bridging the gap between predictability and current skill (split into two groups designed to be random except for Chair and Rapporteur chosen to lead discussion)

3:45 - 5:00 Group 1 (Chair: Jim Kinter; Rapporteur: Mike Tippett)
3:45 - 5:00 Group 2 (Chair: Ben Kirtman; Rapporteur: Huug van den Dool)

Focus Questions:

  • What are the most important scientific questions that need to be answered to bridge the gap between current and potential skill for subseasonal timescales?
  • Without resource limits, how would you approach answering those questions?
  • How would a multi-model ensemble re-forecast contribute to answering those questions?
  • Within resource limits, what system improvements (e.g. horizontal resolution, stratospheric vertical resolution, ensemble size, initialization) are most likely to cost-effectively improve sub-seasonal skill?

Tuesday, March 31 (all times are Eastern Time)

8:00 - 8:30 Coffee/refreshments
8:30 - 8:40 CPC management (Dave DeWitt) presents Appreciation Certificate to the NMME team members for their efforts in developing the NMME Seasonal Forecast System
8:40 - 9:00 Breakout Session Report Back
Group 1 (Jim Kinter)
Group 2 (Ben Kirtman)

Session 5: Needs, requirements, feasibility for deployment of a subseasonal NMME prediction system (Chair: David DeWitt)

9:00 - 9:20 CPC Subseasonal Outlooks and associated NMME needs/requirements (Jon Gottschalck)
9:20 - 9:40 DoD needs/requirements for subseasonal Products - Part 1 (Ryan Harris), Part 2 (David Ramsaur)
9:40 - 10:00 Overview of Research Community Needs (Andrew Robertson)
10:00 - 10:20 NCEP (Suru Saha)

10:20 - 10:30 Coffee Break

Session 6: Breakout Session: Needs and requirements for a subseasonal NMME prediction system (participants self select into community/group they most identify with)

10:30 - 12:00 Group 1: Feasibility, technical and engineering requirements (Discussion
Lead: Jon Gottschalck; Rapporteur: Kathy Pegion)

10:30 - 12:00 Group 2: Research Community Needs & Requirements (Discussion Lead: Andrew Robertson; Rapporteur: Emily Becker)

Focus Questions:

  • What are the needs for a subseasonal NMME prediction system to be useful to your community (both re-forecast and real-time components)?
  • What are the data needs (e.g. format, frequency, flow, access, variables, etc.)?
  • What needs are critical vs. negotiable?
  • What is your ideal system given no limitations on resources?
  • How would you use the system you envision?
  • What are the key benchmarks you consider necessary to demonstrate success of such a system?
  • What are the feasibilities of deploying a NMME subseasonal forecast system including technical, data, and engineering aspects?

12:00 - 1:30 Lunch

1:30 - 2:00 Breakout Report Back
Group 1 (Jon Gottschalck)
Group 2 (Emily Becker)

Session 7: Design of a potential re-forecast experiment that would test the feasibility and skill improvement of an NMME-type sub-seasonal system and set of products compared to other approaches (Chairs: Ben Kirtman and Kathy Pegion)

2:00 - 3:00 Synthesis & Discussion

  • Will present and discuss a proposed subseasonal re-forecast experiment with emphasis on how this will meet operational (e.g. CPC) and research (e.g. S2S + others) needs defined in breakout sessions.
  • Will present and discuss how this experiment can be used to address scientific opportunities (e.g. those discussed in day 1 breakouts).
  • Data issues

3:00 Meeting Adjourns

Closed Meeting

3:00 - 5:00 Organizing Committee Meeting and representatives from operational centers and S2S community.


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