LAUSR

AbstractThe skeleton model is one of the theoretical models for understanding the essence of the Madden–Julian oscillation (MJO). The heating parameterization scheme in the skeleton model assumes that precipitation tendency is in phase and proportional to the low-level moisture anomaly. The authors show that the observed MJO precipitation tendency is not in phase with the low-level moisture anomaly. The consequence of the wave activity envelope (WAE) scheme is reexamined by using a general MJO theoretical framework in which trio-interaction among convective heating, moisture, and wave–boundary layer (BL) dynamics are included and various simplified convective schemes can be accommodated. Without the BL dynamics, the general model framework can be reduced to the original skeleton model. The authors show that the original skeleton model yields a neutral mode that exhibits a “quadrupole” horizontal structure and a quadrature relationship between precipitation and low-level moisture; both are inconsistent wit...