The MJO Precipitating Cloud Population over the Central Indian

Ocean as seen by the TRMM PRHannah C. Barnes

Robert A. Houze, Jr.

University of Washington

MJO Field Data and Science Workshop5 March 2013, Hapuna Beach Resort, Kohala Coast, Hawaii

Precipitating Cloud Population By Phase

Isolated, Shallow Echoes Deep Convective Cores Broad Stratiform Regions

Activ

eSu

ppre

ssed

Relationship Between Precipitating Cloud Population and Large-Scale Conditions

Pre-Active Active Post-Active

Phase 1 2 3 4DCC Peak Decrease

WCC, BSR Increase Peak Decrease

Mid-Level Relative

HumiditySharp

IncreaseSlower

Increase Peak Decrease

1000-750 hPa Shear Increase Peak

750-500 hPa Shear Increase Peak

Large-Scale Conditions

Solid lines = active, dashed = suppressed

Relative Humidity (%)

Pres

sure

(h

Pa)

81 2-3

4

Zonal Wind (ms-1)

12 3

4

MJO Phase

Large-Scale 1000-750 hPa Shear

ms-1

Frequency (%) ISE DCC WCC BSR

Shading = shear

magnitude

Number

MJO Phase

Large-Scale 750-500 hPa Shear

ms-1

Frequency (%) ISE DCC WCC BSR

Shading = shear

magnitude

Acknowledgements

• Funding• DOE DE-SC0001164 / ER-64752 and DE-SC0008452• DYNAMO – NSF AGS-1059611• PMM-NASA Grant NNX10AH70G