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Development plan

Development plan. Strategy. Improvement of the operational model The analysis performance The model performance Ground base GPS data process Development to enhance the model performance Ingest new observations DFI New Grid (OP3) HRLDAS EAKF Ensemble forecast GSI. Improve the analysis.

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Development plan

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  1. Development plan

  2. Strategy • Improvement of the operational model • The analysis performance • The model performance • Ground base GPS data process • Development to enhance the model performance • Ingest new observations • DFI • New Grid (OP3) • HRLDAS • EAKF • Ensemble forecast • GSI

  3. Improve the analysis • Background error tuning is not urgent. • Maxxin’s results suggests to go back to CV3 • Observations • Perform comprehensive OSE to define the impact of the observations in analysis • Improvement strategy • Apply improved data use policy • QC, thinning, and any suggestions? • How to perform a reasonable surface analysis? • Improve the use of GPSRO, AIREP, and SYNOP obs • Suya is not available next year.

  4. Improve the analysis • Improvement in 3DVAR • Improve the analysis quality and shorten the adjust period in forecast. • Improve the analysis quality, in particular for the geopotential height. • Is it reasonable that the analysis is very close to the NCEP GFS analysis with observation coverage area? • Are there fundamental problems in 3DVAR? • The balance relation in the multi-variable analysis? • The translation between analysis variables and model variable? • Can outer loop help anything?

  5. Improve the analysis • Data assimilation framework • Full cycle or limited update cycle? • TBD in Dec. • 1st guess in the nest domain is interpolated from the domain1 • Avoid the possibility that the forecast drift too much between nests. • Using the previous global forecast as boundary condition. • Get more CPU time. • Assimilate the GFS analysis • Suggest to assimilate in the post run to improve the 1st guess • Which model? Domain coverage? Density? Which variables? • Some of the changes will result in the complexity in operation, as well in user maintained data assimilation experiment.

  6. Improve the model performance • Update the model physics to improve the model QPF at 45-km and 20-km resolution • CuP • PBL • Evaluation of the model dynamics • Diffusion • Damping • Continuously monitor the forecast near the lateral boundary

  7. Anomaly Correlation betweenM00 and NCEP analysis1 Jul-31 Aug

  8. Anomaly Correlation betweenM00 and NCEP 24-hr fcst1 Jul-31 Aug 24-hr fcst is better than analysis? Why occurred near lateral boundary

  9. Ground base GPS data process • Works should be done in 2009: • Operation of the PW/ZTD products • Real-time analysis configuration from two hours to one hour. • Investigate variable session lengths (1-6 hours) to create NRT results of equal quality to daily results • Keep daily process procedure • Keep the minor operational maintain and update in 2010

  10. Ingest new observations • ZTD • Schedule to be operational in 2010 • Radiance • We have to promote our domain knowledge for radiance data and its data pre-processing, e.g. bias correction • The analysis performance and its impact on forecast should be carefully re-examed.

  11. Analysis increment (2008060200) con pwv 2 3 1 ztd TUNOE

  12. DFI • To assess the possibility to operate in 2010: • Any side effect? • From case and scores. • Impact on typhoon initialization. • Optimal configuration? • Run DFI in nest domain. • It is a critical issue.

  13. New Grid (OP3) • Operational plan • Continuously keep a user-maintained parallel version following all the operational update. • Parallel from June 2010 (has to be confirmed with control team), and operational in Oct 2010 • For operational OP3, in 2010 and at least early 2011, it is just a member of CWB WRF but provide the products to CAA.

  14. Road map of the OP3 plan Mar 2010 Jun Sep 2011 Operational plan Operation User maintained since May 2009 Parallel Update to OP2.1 and in cyclic mode Development plan Evaluate the cold start performance Evaluate the cycle performance

  15. Major activities • Development plan • Strategy: No tuning on the resolution dependent issues, just increase the model resolution • Evaluation of the cold start performance • Comparison with 45/15 resolution • Update the model version from OP2.1 • Update the 3DVAR component • CV3 will be good to avoid the uncertainty in using the background error covariance interpolated from 45-km resolution. • Apply the limited update cycle? • BC from the previous GFS forecast • Evaluate the OP3 performance in OP2.1 framework (cyclic mode).

  16. Uncertainties • Any possibility that 20-km OP3 is not as good as 45-km OP2.X? • What can we do? • We just have limited experience about the model performance at 20-km resolution • We DON’T have any idea about the data assimilation performance in OP3. • We have to make a consistent plan for the OP3 development including • Model development physics improvement • It is undergoing • Data assimilation resolution dependent issues in 3DVAR tuning • Any suggestions? • Need to improve the I/O performance? • Reduce the hourly output variables

  17. HRLDAS • Operation of coupled HRLDAS • Verification and evaluation the performance of the offline/coupled HRLDAS on forecast against atmospheric and soil observations • Operate on OP2, late 2010. • Operation for MODIAS landuse and climo of the LAI and fPAR • Impact study and evaluation • Update Taiwan soil type database • Process the MODIS albedo climo

  18. GSI • Implement the GSI in CWB environment • Evaluate the performance of GSI/WRF system to be a counterpart of 3DVAR/WRF system.

  19. EAKF and ensemble forecast

  20. 2014 2010 2011 2012 2013 Phase 1 of EFS（EFS/FIFOW） Study and implementation Parallel Operation Phase 2 of EFS (EFS/P5) Operation EFS第一發展階段(EFS/FIFOW)： 在現有資源與技術下，發展與提供FIFOW所需的預報資訊。 EFS第二發展階段(EFS/P5)： 發展新的系集方法、提供更多的成員與模式升級。

  21. EFS/FIFOW solution • Model ：WRF • Resolution ：45/15 km • Domain ： • The same as OP2 • Ensemble members • EAKF • Multi-IC, Multi-physics, multi-model • Operation pattern • 40 member per day • Output frequency: 3-hr

  22. Challenge of EFS/FIFOW • The operation schedule has been defined, no way to change. • How to evaluate the performance of the ensemble forecast? • Develop the verification technique. • Develop the operational affordable ensemble spread technique • Cold start EAKF、multi-IC（different DA strategy）、multi-physics • Which one is the better? • 最後，我們必須能夠用某種方法或成果告訴預報中心，我們提供的系集預報是「好」到什麼程度，或者不好到什麼程度。 • Optimal use of the computer resources • Produced the useful ensemble products. • Downscale to station • Grid product

  23. EAKF • Role of EAKF • EAKF data assimilation • Cycle • EAKF ensemble forecast • Cold start EAKF • Cycle EAKF

  24. perturb fg fcst perturb fg M1 M1 F1 F1 A1 M2 F2 F2 M2 A2 F3 F3 A3 M3 M3 :: :: :: :: :: Fn Mn Fn Mn An EFS1 Cold start EAKF on EFS EAKF EFS2 fcst obs Ensemble mean posterior fcst Posterior analysis fcst Cycle EAKF on DA for deterministic and ensemble forecast

  25. Role of WAKF in CWB • Apply the cold start EAKF for the requirement of FIFOW • EFS1EFS/FIFOW • Ensemble forecast from EAKF-DA（cycle） • EFS2EFS/P5 • Better than cold start-EAKF ？ • Posterior forecast from EAKF-DA（cycle）could be one of the deterministic forecast • Better than 3DVAR/WRF system？ • Ensemble mean provided from EAKF-DA（cycle）ensemble forecast • Better than posterior forecast？

  26. Challenge of EAKF • To answer: • For ensemble forecast: Cold start EAKF (EFS1) v.s. cycle EAKF(EFS2) • For deterministic forecast: EAKF-posterior fcst v.s. EAKF EFS mean v.s. 3DVAR fcst • EAKF results spread enough on Ensemble forecast (cold start or cycle) • We need to develop ensemble verification technique • EAKF on Data assimilation (cycle) • Analysis performance • Does perturbation spread enough after long time assimilation? How to evaluate? • Is EAKF posterior analysis good enough? How to evaluate? • How does the individual member analysis perform? How to evaluate? • What is the optimal member number? Anyway to reduce the member? (e.g. time lag) • Impact on posterior forecast • Improve forecast or not? • Need to improve computing efficiency? • Affordable in current HPC resource? • Promote the knowledge of the EAKF • So that we can ask the right questions and properly evaluate their solutions

  27. Strategy of EAKF development plan in 2010-2011 • Ensemble forecast • Setup and evaluate the cold start EAKF system (EFS1) • Develop the verification technique • Evaluate the spread in the initial and forecast • DA • Evaluation the posterior forecast system on forecast • Compare with 3DVAR system • User-maintained posterior forecast system in OP2.X framework in 2010

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