The 23rd Conference on Hurricanes and Tropical Meteorology

10B.4
THE COUPLING BETWEEN CONVECTION AND LARGE-SCALE MOTION ASSOCIATED WITH THE MADDEN-JULIAN OSCILLATION (MJO) OBSERVED DURING TOGA-COARE IOP

Wen-wen Tung, UCLA, Los Angeles, CA; and M. Yanai

Coupling between convection and large-scale motion associated with two MJO events observed during the TOGA-COARE IOP is investigated. Super cloud clusters associated with the MJOs induce positive temperature anomalies in the upper troposphere when propagating from the Indian Ocean to the western Pacific. The apparent heat source, Q1, and the moisture sink, Q2, are calculated from ECMWF reanalysis refined by TOGA-COARE high resolution upper-air sounding. By applying the Rotated Principal Component Analysis (RPCA) to the vertical Q1 and Q2 profiles, a dominant mode of deep convection is found. Over the western Pacific Ocean, this mode displays strong correlation with the convective phase of MJO. However, this correlation is not clear over the Indian Ocean. The comparisons will be made between the convection regimes obtained from TOGA-COARE and GATE Phase III datasets. Finally, A schematic model is constructed to illustrate the convective phase of MJO across the tropical Indian Ocean-western Pacific sector

The 23rd Conference on Hurricanes and Tropical Meteorology