1. ISU Atmospheric Component Update – Part I 3 rd RASM Workshop 2012 Fall Justin Glisan Iowa State University

2. Update Spectral nudging paper accepted by J. Clim. – Research funded through original DOE RACM grant – Co-authors: W.J. Gutowski, J.J Cassano, & M.E. Higgins Remaining two papers will be submitted to JGR Postdoctoral SOMs research 2

3. J.Clim. Paper Background Long and short PAW simulations were run on the RACM domain A systematic, atmosphere-deep circulation bias formed within the northern Pacific storm track Various remedies tested, but with little success Spectral or interior nudging was introduced

4. J. Clim. Paper Conclusions Winter behavior more sensitive to nudging Improve Cold Season Mean and Extreme Behavior – Stronger SN for precipitation – Weaker SN for surface temperatures Improve Warm Season Mean and Extreme Behavior – Weaker SN for precipitation – Stronger SN for surface temperatures 4 Optimal range for pan-Arctic simulations: 1/8 th – 1/16 th the WRF default

5. ISU Atmospheric Component Update – Part II 3 rd RASM Workshop 2012 Fall Brandon J. Fisel Iowa State University Department of Geological and Atmospheric Sciences Tucson, AZ 13-15 November

6. OVERVIEW 3 rd RASM November 2012  Leap day in RASM  Solved!  WRF BC’s file name bug  ISU plans

7. RASM LEAP DAY 3 rd RASM November 2012  Possible shift in WRF calendar?  Compared lagged ERA-Interim (-48, -24, +24 hrs) with RASM (bad leap, non- spectral, no Feb. 29).  e.g., -48 hr lag -> ERA-Interim:1992- Feb-28-00 UTC – RASM:1992-Mar-01- 00 UTC.  Nothing suggestive of a WRF calendar problem (boundary discontinuities continue through simulation).

8. r31RBa2 (-48 hrs)r31RBa2 (-24 hrs) r31RBa2 (+24 hrs)

9. RASM LEAP DAY 3 rd RASM November 2012  LBC tendencies are computed on-the-fly in real.exe (share/module_bc -> stuff_bdytend subroutine).  Modifications made to met_em files.  2 methods:  1) blend (Seefeldt)

10. Method 1: met_em.d01.1992-02-28_00:00:00.nc -> met_em.d01.1992-02-28_00:00:00.nc met_em.d01.1992-02-28_12:00:00.nc -> met_em.d01.1992-02-28_06:00:00.nc met_em.d01.1992-02-29_00:00:00.nc -> met_em.d01.1992-02-28_12:00:00.nc met_em.d01.1992-02-29_12:00:00.nc -> met_em.d01.1992-02-28_18:00:00.nc met_em.d01.1992-03-01_00:00:00.nc -> met_em.d01.1992-02-29_00:00:00.nc February 29 06, 12 and 18 UTC times left alone because those times are not important to RASM and will be removed from wrfbdy and wrffdda files after real.exe is completed.

11. RASM LEAP DAY 3 rd RASM November 2012  LBC tendencies are computed on-the-fly in real.exe (share/module_bc -> stuff_bdytend subroutine).  Modifications made to met_em files.  2 methods:  1) blend (Seefeldt)  2) time-stagger

12. Method 1: met_em.d01.1992-02-28_00:00:00.nc -> met_em.d01.1992-02-28_00:00:00.nc met_em.d01.1992-02-28_12:00:00.nc -> met_em.d01.1992-02-28_06:00:00.nc met_em.d01.1992-02-29_00:00:00.nc -> met_em.d01.1992-02-28_12:00:00.nc met_em.d01.1992-02-29_12:00:00.nc -> met_em.d01.1992-02-28_18:00:00.nc met_em.d01.1992-03-01_00:00:00.nc -> met_em.d01.1992-02-29_00:00:00.nc Method 2: met_em.d01.1992-02-28_12:00:00.nc -> met_em.d01.1992-02-28_12:00:00.nc met_em.d01.1992-02-28_18:00:00.nc -> met_em.d01.1992-02-28_18:00:00.nc met_em.d01.1992-03-01_00:00:00.nc -> met_em.d01.1992-02-29_00:00:00.nc February 29 06, 12 and 18 UTC times left alone because those times are not important to RASM and will be removed from wrfbdy and wrffdda files after real.exe is completed. After modification of met_em files, real.exe is run like usual. Following generation of wrfbdy and wrffdda files, February 29 is removed from files. Scripts available on Garnet to make modifications to met_em and BC files.

13. r30RB1gr31RBa31 (method 1) r31RBa32 (method 2)r31RBa31-r31RBa32

14. RASM LEAP DAY 3 rd RASM November 2012  LBC tendencies are computed on-the-fly in real.exe (share/module_bc -> stuff_bdytend subroutine).  Modifications made to met_em files.  2 methods:  1) blend (Seefeldt)  2) time-stagger  both methods produced similar results; method 2 more simple  New files ready for use in RASM.

15. WRF BC NAME BUG 3 rd RASM November 2012  Namelist setting allows user to specify a different name for BC files.  Bug – name overwritten to the default value (WRF v. 3.2 – 3.4.1).  issue with new leap-day BC file names  WRF unable to find new Feb. files  Mediation_integrate.F

16. IF (.NOT. lbc_opened ) THEN CALL construct_filename1 ( bdyname, 'wrfbdy', grid%id, 2 ) WRITE(message,*)'Opening: ',TRIM(bdyname) CALL wrf_debug(100,TRIM(message)) CALL open_r_dataset ( grid%lbc_fid, TRIM(bdyname), grid, config_flags, "DATASET=BOUNDARY", ierr ) IF ( ierr.NE. 0 ) THEN WRITE( message, * ) 'med_latbound_in: error opening ',TRIM(bdyname), ' for reading. IERR = ',ierr CALL WRF_ERROR_FATAL( message ) ENDIF CALL construct_filename2a ( bdyname, grid%bdy_inname, grid%id, 2, " " ) IF (.NOT. lbc_opened ) THEN WRITE(message,*)'Opening: ',TRIM(bdyname) CALL open_r_dataset ( grid%lbc_fid, TRIM(bdyname), grid, config_flags, "DATASET=BOUNDARY", ierr ) IF ( ierr.NE. 0 ) THEN WRITE( message, * ) 'med_latbound_in: error opening ',TRIM(bdyname), ' for reading. IERR = ',ierr CALL WRF_ERROR_FATAL( message ) ENDIF

17. WRF BC NAME BUG 3 rd RASM November 2012  Namelist setting allows user to specify a different name for BC files.  Bug – name overwritten to the default value (WRF v. 3.2 – 3.4.1).  issue with new leap-day BC file names  WRF unable to find new Feb. files  Mediation_integrate.F  WRF folks will implement this fix in the next version.

18. OVERVIEW 3 rd RASM November 2012  Leap day in RASM  ISU plans  Ongoing work  Key questions  Diagnostics  Observational and GCM data  Coupler/WRF output

19. ISU PLANS - ONGOING WORK 3 rd RASM November 2012  Ongoing regimes and extremes work:  Expanded the analysis to 17 years (1991 – 2007) using 6-member ensemble CORDEX simulations.  Key questions:  Is there a similar breakdown in the occurrence of seasonal regime behavior?  Do we see more persistent regime behavior becoming the “norm” during summer in recent years when sea ice is rapidly declining?

20. ISU PLANS - QUESTIONS 3 rd RASM November 2012  ISU research questions:  What effect does rapid loss in sea ice have on the energy/moisture budgets? Also in the future?  Current and future spatial variations in energy/moisture budgets and relation to regime behavior change for same spatial areas? What effect is there on extremes in these regions?

21. ISU PLANS - QUESTIONS 3 rd RASM November 2012  ISU research questions (continued):  If sea ice continues to rapidly decline thereby also delaying the re-freezing of sea ice, allowing more heat to be released by the ocean into the atmosphere, what effect does this have on future regime behavior?  How will regimes change in the future? Will the change in regime behavior be regionally dependent?  What effect would changing regime behavior have on extremes in the future Arctic? A more extreme Arctic?

22. ISU PLANS - DIAGNOSTICS 3 rd RASM November 2012  Diagnostics:  Monthly, seasonal and long-term (~20 years) energy/moisture budget computations.  Temporal and spatial variations on energy/moisture budget terms on interannual and decadal time scales.  How do modeled (RASM) versus prescribed (stand-alone WRF) SST affect regime behavior?  Do RASM simulations have similar regime behavior over the same time period?

23. ISU PLANS - DIAGNOSTICS 3 rd RASM November 2012  Diagnostics (continued):  Sensitivity of RASM energy and moisture budgets to model resolution.  How does the NAO and AO affect regime behavior?  Influence of feedbacks in RASM versus stand- alone WRF (cice+ocn+vic+datm).  What is the interannual and decadal variability of the net radiation from the ocean?

24. ISU PLANS - OBS DATA 3 rd RASM November 2012  Observation data:  ERA-Interim (BC’s)  Global Precipitation Climatology Project  GEWEX Continental Scale International Project (GAPP) Surface Radiation Budget (SRB)  Pathfinder high resolution surface radiative fluxes  Canadian Meteorological Centre daily snow depth analysis data  Global Snow-Water-Equivalent Depth Coefficient-of-Variation Classification

25. ISU PLANS - OBS DATA 3 rd RASM November 2012  Observation data (continued):  Atmospheric Radiation Measurement (ARM) Climate Research Facility  AMSR-E/Aqua Daily 12.5 km Brightness Temperature, Sea-Ice Concentration, & Snow Depth Polar Grids

26. ISU PLANS - GCM DATA 3 rd RASM November 2012  GCM data:  For future RASM simulations, what GCM BC’s should be used? (e.g., ECHAM5 and HADCM3)  Sea ice declining faster than in GCM’s. Future sea-ice decline in RASM vs. GCM’s? Image courtesy of: Stroeve et al., 2007. GRL doi:10.1029/2007GL029703 Sea ice (brown) declining faster than GCM ensemble mean (solid black).

27. ISU PLANS - OTHER DATA 3 rd RASM November 2012  Coupler and WRF data:  Instantaneous vs. average output.  Need instantaneous values of state variables for budget studies.  T, Q, U, V, ect.

28. SUMMARY 3 rd RASM November 2012  WRF leap-day issue solved.  WRF namelist bug submitted to wrfhelp.  ISU will evaluate energy/moisture budgets in RASM with focus on physical links between budgets and regimes/extremes.  GCM data – what GCMs?  Need instantaneous values for energy/moisture budget studies.