1. The Convective Cloud Population during the Buildup of the Madden- Julian Oscillation AGU Fall Meeting, San Francisco, 7 December 2011 R. Houze, S. Brodzik, J. Yuan University of Washington

2. The Convective Cloud Population during the Buildup of the Madden- Julian Oscillation Three perspectives: A-Train DYNAMO TRMM Still going on!

3. The MJO

4. Wheeler and Hendon 2004 Phases of the MJO

5. TRMM

6. Phase 1Phase 5 Phase 7Phase 3 Frequency of radar echo in “broad stratiform regions” of MCSs

7. Phase 7Phase 3 Phase 1Phase 5 Frequency of radar echo in “deep convective cores”

8. Phase 7Phase 3 Phase 1Phase 5 Frequency of “shallow isolated” radar echoes (anomaly)

9. Variation of Echo Category with MJO Phase

10. A-Train

11. Mesoscale Convective Systems (MCSs) have cold tops and large intense raining cores Both raining and anvil components are identified using A-Train instruments

12. CMCSs SMCSs HCSs excl.MCSs non-HCSs Percentage % a) Cloud coverage b) Contribution to precipitation “Connected MCSs” “Separated MCSs” Other High Cloud Systems Non-high-cloud Systems

13. DYNAMO

14. Cloud Structures (NCAR S-PolKa radar)

15. Suppressed phase: Lines of non- precipitating clouds

16. Suppressed phase: Clouds at cold pool boundaries

17. Suppressed phase: Clouds at cold pool boundaries

18. 4 km 8 km graupel small ice large non-melting ice heavy rain Small cumulonimbus melting snow

19. Small, weak stratiform area

20. Active phase: Large mesoscale system Stratiform Convective

21. 5 km 10 km Robust melting layer in Large MCS

22. Convection feeding into a large MCS

23. Shear

24. Low-level westerly component, upper-level easterly component NE SW

25. Biggest MCS of first active phase: weak unidirectional shear

26. Larger-than-mesoscale Organization

27. Giant Rings of Convection

28. Westerly Surges

30. End This research is supported by NSF grant ATM AGS-1059611, DOE grant DE-SC0001164/ER-64752, and NASA grants NNX10AM28G and NNX10AH70G

31. Extras

41. Identify each contiguous 3D echo object seen by TRMM PR Convective component Stratiform component Extreme characteristic Contiguous 3D volume of convective echo > 30 dBZ Top height > 8 km “Deep convective core” Horizontal area > 800 km 2 Horizontal area > 800 km 2 “Wide convective core” Extreme characteristic Contiguous stratiform echo with horizontal area > 50 000 km 2 “Broad stratiform region” Categories of radar echoes seen by TRMM

44. MODIS TB11 + AMSR-E ( Yuan and Houze 2010) combined to find“cold centers” & “raining areas” Use 260 K threshold Locate 1 st closed contour Use 1 mm/h threshold for rain rate Associate pixels with nearest cold center Use 6 mm/h threshold for heavy rain

45. 1 2 3 4 5 6 7 8 Phase

46. Pressure (hPa) Phases 1,8 Phases 2,3 Phases 4,5 Phases 6,7 50 E 100 E 150 E 200 E DYNAMO Mixing ratio anomaly 1000 600 200 1000 600 200

47. Descent of easterlies