This study investigates: (i) how the local meridional (Hadley) and zonal (Walker) circulations change in each phase of Madden-Julian Oscillation (MJO); (ii) effect enhanced suppressed MJO-related convection on poleward extent Hadley and, thus, strengths positions subtropical jets. We examine these effects ERA-Interim reanalysis by decomposing vertical mass flux into components. show for first t...

Numerical experiments with a 2.5-layer and a 2-level model are conducted to examine the mechanism for the planetary scale selection of the Madden–Julian oscillation (MJO). The strategy here is to examine the evolution of an initial perturbation that has a form of the equatorial Kelvin wave at zonal wavenumbers of 1 to 15. In the presence of a frictional boundary layer, the most unstable mode pr...

1 Lamont-Doherty Earth Observatory, Earth Institute at Columbia University, 61 Rte. 9W, Palisades, NY 10964, USA. 2 Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York, USA. 3 Department of Earth and Environmental Sciences, Columbia University, New York, New York, USA. 4 School of Earth and Environmental Sciences, Seoul National University, San 56-1, S...