1 / 25

Review of Recent Results, Ongoing Development & Testing Plans For implementation

Review of Recent Results, Ongoing Development & Testing Plans For implementation. Bo Cui 1 , Zoltan Toth 2 , Yuejian Zhu 2 , Richard Verret 3 1 SAIC at Environmental Modeling Center, NCEP/NWS 2 Environmental Modeling Center, NCEP/NWS

umeko
Download Presentation

Review of Recent Results, Ongoing Development & Testing Plans For implementation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Review of Recent Results, Ongoing Development & TestingPlans For implementation Bo Cui1, Zoltan Toth2, Yuejian Zhu2, Richard Verret3 1SAIC at Environmental Modeling Center, NCEP/NWS 2Environmental Modeling Center, NCEP/NWS 3Canadian Meteorological Centre, Meteorological Service of Canada Acknowledgements David Unger, Stéphane Beauregard, Dingchen Hou, Richard Wobus

  2. Review of Recent Results • First moment correction: • Previous results: kept reinitializing the prior, based on 40-day flat average difference • Current system: keeps cycling the bias estimate after initializing the prior, which starts from July 1, 2003. Choose decaying weight 10%, 5%, 2%, 1%, 0.5% and 0.25%, respectively, and apply on 500 mb height of NCEP & CMC ensemble • Northern and Southern Hemisphere: the smaller weigh is better for longer lead time, and larger weight is better for shorter lead time • Tropical region: 2% is the best one among the six weight factors • Bias correct CMC member individually & bias correct CMC member in 2 groups ( 8 SEF member & 8 GEM member) due to CMC multi- model ensemble and each model & member has its own physics parameterization • applying the bias correction scheme on each member is the better approach though the differences are small between the two methods • Combined ensemble, use equal weight for all members ( 5 NCEP & 5 CMC member)

  3. Ongoing Development & Testing Plans for Implementation • Bias correction • First moment correction • choose a fixed weigh factor (2 % as a default), or vary it as a function of lead time and location ( how to determine variations?) • apply bias correction scheme to 35 variables ( NCEP & CMC ) • apply bias correction on 1 x1 degree ensemble data (NCEP & CMC ) • apply bias correction on 00z and 12Z (NCEP & CMC, 06 &18Z for NCEP ) • Second moment correction • may not be included in next spring operational implementation • Weighting • BMA method: only tested for surface temperature • Dave Unger’s scheme based on skill measure • If 1 or 2 don’t improve skill, use equal weight for all members in the combined ensemble for next spring implementation

  4. List of Variables for Bias CorrectionCMC & NCEP Ensemble

  5. NCEP RPSS: 500mb Height, Northern Hemisphere 2004 Annual Mean http://www.emc.ncep.noaa.gov/gmb/wx20cb/Bias_Correction_Algorithm/1st_2nd_Moments/Training_1month/Plot_Comb_Post/z500_2004_ncep_annual/

  6. NCEP PAC: 500mb Height, Northern Hemisphere 2004 Annual Mean

  7. NCEP RMS: 500mb Height, Northern Hemisphere 2004 Annual Mean

  8. NCEP RPSS: 500mb Height, Southern Hemisphere 2004 Annual Mean

  9. NCEP PAC: 500mb Height, Southern Hemisphere 2004 Annual Mean

  10. NCEP RMS: 500mb Height, Southern Hemisphere 2004 Annual Mean

  11. NCEP RPSS: 500mb Height, Tropical 2004 Annual Mean

  12. NCEP PAC: 500mb Height, Tropical 2004 Annual Mean

  13. NCEP RMS: 500mb Height, Tropical 2004 Annual Mean

  14. CMC RPSS: 500 mb Height, Northern Hemisphere March, 2005 – May, 2005

  15. CMC RMS: 500mb Height, Northern Hemisphere March, 2005 – May, 2005

  16. CMC PAC: 500mb Height, Northern Hemisphere March, 2005 – May, 2005

  17. CMC RPSS: 500 mb Height, Northern Hemisphere March, 2005 – May, 2005

  18. CMC RPSS: 500 mb Height, Northern Hemisphere June, 2005 – July, 2005

  19. Combined RPSS (5 NCEP & 5 CMC) 500 mb Height, Northern Hemisphere, Jan 15 2005 – Feb 28 2005 * Data from old system

  20. Combined RPSS (5 NCEP & 5 CMC) 500 mb Height, Southern Hemisphere, Jan 15 2005 – Feb 28 2005 * Data from old system

  21. Questions and Comments?

  22. NCEP PAC: 500mb Height, Northern Hemisphere March, 2005 – May, 2005

  23. NCEP RPSS: 500mb Height, Northern Hemisphere March, 2005 – May, 2005

  24. NCEP RMS: 500mb Height, Northern Hemisphere March, 2005 – May, 2005

  25. Correlation Between the Observed Anomalies and Fcst Errors • Preliminary Results The ens. mean fcst. error is a function of lead time. The correlation between the observed anomalies and the ens. mean fcst error is very high. This suggests that the ens. mean fcst error is dominated by the observed verifying anomalies. The time mean errors may not be closely related to systematic errors. • Future plan remove the observed anomaly from the error fields before they are used as estimates of the bias. • Method • decompose the total error into (a) component parallel to obs. anomaly; • (b) residual error, orthogonal to obs. Anomaly ( M. Wei ). • remove error component along obs. anomaly from total error and work with residual component for bias estimation.

More Related