1. MM5 SIMMULATIONS OF SFBA TO SAC/SJV TRANSPORT DURING 30 JULY- 2 AUG 2000 CCOS OZONE EPISODE by Robert D. Bornstein: SJSU pblmodel@hotmail.com Tesfamichael B. Ghidey: LBNL, SJSU Robert Van Buskirk: LBNL Prepared for GMU Workshop July 2004

2. OUTLINE SYNOPTIC SUMMARY SYNOPTIC SUMMARY –700 MB (NO MESO INFLUENCES OVER CALIF) –SFC MM5 CONFIGURATION MM5 CONFIGURATION DOMAIN 1: SYNOPTIC WINDS DOMAIN 1: SYNOPTIC WINDS DOMAIN 3: MEOS WINDS DOMAIN 3: MEOS WINDS –LIV, SAC, & SJV SEQUENTIAL OZONE EPISODE DAYS STAT MESO-EVALUATION STAT MESO-EVALUATION –TEMP MESOSCALE: TEMP DRIVES WINDS MESOSCALE: TEMP DRIVES WINDS SYN SCALE: MASS/PRESSURE DRIVES WINDS SYN SCALE: MASS/PRESSURE DRIVES WINDS –WINDS (MESO CONVENTION) FULL BARB = 1 M/S FULL BARB = 1 M/S FLAG = 5 M/S FLAG = 5 M/S CONCLUSION CONCLUSION

3. FORCINGS EPISODES OCCUR ON GIVEN DAYS EPISODES OCCUR ON GIVEN DAYS –NOT B/C TOPO, EMISSIONS, OR SFC MESO- FORCING (EXCEPT FOR FOG) CHANGES –BUT B/C UPPER LEVEL SYNOPTICS CHANGE, WHICH ALTERS MESO-FORCINGS (TOPO, LAND/SEA, URBAN) VIA T AND THUS V MUST THUS EVAL ALL ABOVE FACTORS: MUST THUS EVAL ALL ABOVE FACTORS: SYN, TOPO (grid spacing), MESO T & V

4. 700 hPa NWS PREVIEW: 1200 UTC OR 0500 PDT Movement of inland H causes episodes Movement of inland H causes episodes Pre-episode: over Nevada Pre-episode: over Nevada Episode days: moves SW to over SJV Episode days: moves SW to over SJV and intensifies and intensifies Post-episode: dissipates Post-episode: dissipates

5. Before ozone episodes: offshore G. C. High; synoptic High in Nevada; boundary-Low between Highs; SSW-flow over SFBA

6. SAC ozone day: SJV Syn H at max intensity; SW flow over SFBA

7. Surface NWS PREVIEW: 1200 UTC or 0500 PDT Warm-core upper-H projects down to a sfc inverted thermal-L Warm-core upper-H projects down to a sfc inverted thermal-L –Pre-episode: over Nevada –Episode days: moves over SJV and intensifies –Post-episode: weakens

8. B/F ozone episodes: warm core “inverted thermal L” from Sea of Cortez to S-Nevada; 2 nd open-L into northern CA; NW-flow over SFBA and S-flow over SAC

9. LIV episode day: trough moves NW, forms closed low, with N-S axis thru central CA; SE-flow over Sac

10. MM5 configuration Version 3.6.0 Version 3.6.0 Three domains Three domains –36, 12, 4 km –55 x 55, 91 x 91, 190 x 190 grid points 32 sigma levels 32 sigma levels –up to 100 mb –first full sigma level at 19 m GDAS IC and BC GDAS IC and BC Analysis nudging only for V and T for Analysis nudging only for V and T for –36 km domain –above PBL No obs nudging No obs nudging Five layer soil model, Gayno-Seaman PBL Five layer soil model, Gayno-Seaman PBL Start: 1200 UTC on 28 July and went for 7.5 days Start: 1200 UTC on 28 July and went for 7.5 days LBNL LINUX single processor: 15 days LBNL LINUX single processor: 15 days

14. MM5 Domain-1: 700 hPa WINDS PREVIEW NWS charts NWS charts –give only approx p-center locations –cannot give flow details in SFBA, Carquinez Straits, & SJV Thus need MM5 to show Thus need MM5 to show –Pre-episode H: E of SFBA over NEV –Episode days: bulge from H extends westward over SFBA –Post-episode H: back-E of SFBA over AZ

15. H L H (B/F episodes) MM5 correct: offshore GC H; Syn H in SE Nev; boundary-L; but S-flow over SFBA vs. SW NWS but S-flow over SFBA vs. SW NWS

16. H H L SAC episode day: Syn H to Utah with max (now NE-SW) “bulge” (vs. NWS-H over SJV) L now S in Cal (vs. NWS: E over CA/Az border); correct SW flow over SFBA to Sac

17. MM5 Domain-1: SFC WINDS PREVIEW (12 UTC OR 05 PDT) Movement to N of thermal L from S-CA sequentially cause episodes Movement to N of thermal L from S-CA sequentially cause episodes –Convergence into LIV –Increased flow to Sac from SFBA –Increased flow into SJV from SFBA –Moves offshore Flow details: in Domain-3 Flow details: in Domain-3

18. L L B/F episodes: warm-core thermal-L to S-Nevada & 2 nd CA-L to N (both correct); NW-flow over coast & SFBA (correct) and con-flow over SAC (vs NWS S-flow)

19. L SAC episode: S-Low moved N & N-Low moved bit S (NWS showed only closed-L gone); now more W-flow to Sac L

20. MM5 SFC-TEMP STATS DAY AND NIGHT SPATIAL-PATTERNS ARE REASONABLE (NOT SHOWN) DAY AND NIGHT SPATIAL-PATTERNS ARE REASONABLE (NOT SHOWN) STATS SHOW SOME BIAS (SHOWN), WHICH CAN BE ELIMINATED BY STATS SHOW SOME BIAS (SHOWN), WHICH CAN BE ELIMINATED BY –SELECTING TRUSTWORTHY SITES –ADJUSTING DEEP SOIL TEMP AND SOIL MOISTURE CONTENT

23. DOMAIN-3: 700 hPa PREVIEW (2100 UTC or 0200 PDT) Offshore-H formation & Fresno eddy movement cause episodes Offshore-H formation & Fresno eddy movement cause episodes Initial flow from S does not produce SFBA to Sac transport Initial flow from S does not produce SFBA to Sac transport Syn-H formation directs SFBA flow to Sac & con- current Fresno eddy blocks SFBA flow into SJV Syn-H formation directs SFBA flow to Sac & con- current Fresno eddy blocks SFBA flow into SJV When eddy moves to N When eddy moves to N –SFBA flow into Sac is blocked –SFBA flow into SJV is allowed

24. Pre-episode: uniform S-flow

25. H L SAC episode: H moved to W at coast (vs bulge from CV to coast in D-1); Fresno eddy N of D-1 position (blocks flow into SJV from SFBA; W flow over SFBA (vs. NWS S-flow) directly to SAC

26. L H SJV episode: Fresno eddy moved N & H moves inland (both better defined than in D-1); flow around eddy blocks SFBA flow to SAC, but forces it S into SJV

27. DOMAIN-3: SUMMARY OF SFC TRANSPORT TO LIVERMORE (KEY HOURS) Daytime confluence of 3-flows E of LIV (on Mt peak) causes episode Daytime confluence of 3-flows E of LIV (on Mt peak) causes episode –Flow from N from Carquinez Straits –Flow from W thru GGG –Upslope from E-side of hills E of LIV For episode need For episode need –Strong confluence –Low speeds

28. Sfc winds obs at 0700 PST (1500 UTC) on 31 July, (LIV episode morning) Note con flow into LIV

29. Sfc-wind Obs at 1400 PST (2200 UTC) on 31 July (LIV episode afternoon) Note flow from N into LIV and out to E

30. Pre-episode afternoon (1400 PDT): W flow thru GGG & weak con into E-Liv

31. Episode afternoon (1400 PDT): W flow thru GGG & strong con into E-Liv

32. DOMAIN 3: SFC TRANSPORT TO SAC SUMMARY TRANSPORT FROM SFBA BLOCKED BY OPPOSING FLOW ON DAYS BEFORE AND AFTER SAC EPISODE TRANSPORT FROM SFBA BLOCKED BY OPPOSING FLOW ON DAYS BEFORE AND AFTER SAC EPISODE TRANSPORT FROM SFBA NOT BLOCKED ON DAY OF SAC EPISODE TRANSPORT FROM SFBA NOT BLOCKED ON DAY OF SAC EPISODE

33. LIV-episode late-afternoon (1800 PDT): flow to SAC from SFBA blocked

34. SAC-episode late-afternoon (1800 PDT): flow to SAC from SFBA not blocked

35. DOMAIN 3: SFC TRANSPORT TO SJV SUMMARY TRANSPORT FROM SFBA TO SJV MUST NOT BE BLOCKED BY OPPOSING FLOWS TRANSPORT FROM SFBA TO SJV MUST NOT BE BLOCKED BY OPPOSING FLOWS FLOW INTO SJV MUST FLOW INTO SJV MUST –NOT BE TOO FAST –SHOW CONFLUENCE

36. SAC EPISODE NIGHT: TRANSPORT TO SJV FROM SFBA IS BLOCKED

37. SJV EPISODE NIGHT: TRANSPORT TO SJV FROM SFBA & CON WINDS

42. CONCLUSION SMALL CHANGES IN 700 MB-H AND SFC-L POSITIONS CAUSED SEQUENTIAL DAILY OZONE MAX IN LIV, SAC, AND SJV SMALL CHANGES IN 700 MB-H AND SFC-L POSITIONS CAUSED SEQUENTIAL DAILY OZONE MAX IN LIV, SAC, AND SJV NWS CHARTS COULD NOT DISCERN DETAILS OF CHANGES, BUT MM5 COULD NWS CHARTS COULD NOT DISCERN DETAILS OF CHANGES, BUT MM5 COULD MM5 MM5 –MATCHED NWS PATTERNS AND MESO-OBS REASONABLY WELL –PROVIDED ADDITIONAL DETAILS ADDITIONAL SIMULATIONS SHOULD CORRECT REMAINING DIFFERENCES ADDITIONAL SIMULATIONS SHOULD CORRECT REMAINING DIFFERENCES