The initiation of the Madden–Julian Oscillation

The mechanics of initiation of the Madden-Julian Oscillation (MJO) remains an open question to the atmospheric community. A modified version of the fifth generation Pennsylvania State University (PSU)-National Center for Atmospheric Research (NCAR) Mesoscale Model (MM5), in the form of a tropical channel is used to study the initiation and organization of convection associated with the MJO. Unlike the general circulation models, this model can be utilised to diagnose the effect of different forcing in the MJO by controlling the boundaries. The other advantage of this modeling approach is the flexibility in choosing the model physics and resolution. The initiaiton of the MJO in the model is not sensitive to the initial time, or the sea surface temperature. Use of constant boundary conditions show large deviation from the control simulation, which indicates that the extratropical forcing may be important in the MJO initiation.