The moisture budget associated with the eastward-propagating Madden–Julian oscillation (MJO) was diagnosed using 1979–2001 40-yr ECMWF Re-Analysis (ERA-40) data. A marked zonal asymmetry of the moisture relative to the MJO convection appears in the planetary boundary layer (PBL, below 700 hPa), creating a potentially more unstable stratification to the east of the MJO convection and favoring th...

5 This work studies the significance of asymmetry in systems of organized convection asso6 ciated with the Madden-Julian oscillation (MJO). Satellite infrared brightness temperature 7 data for the period 1983–2006 were decomposed into subsets symmetric and antisymmetric 8 about the equator. Using a recent nonlinear objective method called nonlinear Laplacian 9 spectral analysis, modes of variab...

The barrier layer, the layer between the bottom of the density-defined mixed layer and the isothermal layer in the upper ocean, may play a role in air-sea dynamics. In the present study, data from Argo profiling floats in the tropical Indian Ocean and a mooring at 90 E, 0 N are used to examine subseasonal variations in upper ocean salinity and barrier-layer thickness (BLT) during boreal winter....

Broadly speaking, the influence of the MJO on precipitation over the tropics occurs by eastward propagation of Rossby wave trains from the tropical Pacific Ocean (Muza et al. 2009). Previous observational and modeling studies generally indicated that MJO and ENSO has a decadal variation and seasonal dependence (Tang and Yu, 2008; Hendon et al. 2007), however, them has not been well identified d...

A kinetic energy budget for the Madden–Julian oscillation (MJO) is established in a three-scale framework. The three scales are the zonal mean, the MJO scale with wavenumbers 1–4, and the small scale with wavenumbers larger than 4. In the composite budget, the dominant balance at the MJO scale is between conversion from potential energy and work done by the pressure gradient force (PGF). This b...

Low-level barotropic dynamics may help to explain the modulation of eastern and western North Pacific tropical cyclones by the Madden–Julian oscillation (MJO) during Northern Hemisphere summer. The MJO is characterized by alternating periods of westerly and easterly 850-mb zonal wind anomalies across the tropical Pacific Ocean. When MJO 850-mb wind anomalies are westerly, small-scale, slow-movi...

[1] Variability of the cloud population in the central equatorial Indian Ocean was observed in the context of the Madden-Julian Oscillation (MJO) during the Dynamics of the MaddenJulian Oscillation (DYNAMO) and Atmospheric Radiation Measurement Madden-Julian Investigation Experiment (AMIE) field campaigns. Radar observations from the polarimetric S-band radar on Addu Atoll in theMaldives charac...

The Madden-Julian Oscillation (MJO) is a tropical atmospheric phenomenon, associated with periods of active convection in the eastern hemisphere tropics.The MJOs temporal scale (22-90 days) coincides with a gap between weather (synoptic forecasts out to 10 days) and climate (seasonal and longer forecasts).Analysis of 35 years of daily rainfall data shows significant modulation of tropical and e...

The large-scale vertical moist thermodynamic structure of the Madden–Julian oscillation (MJO) was documented using the first 2.5 yr (2002–05) of version 4 atmospheric specific humidity and temperature profiles from the Atmospheric Infrared Sounder (AIRS). In this study, this issue is further examined using currently available 7-yr version 5 AIRS data (2002–09) to test its dependence on the AIRS...

The Madden–Julian oscillation (MJO) is the dominant mode of tropical intraseasonal variability, characterized by an eastward-propagating envelope of convective anomalies with a 30–70-day time scale. Here, the authors report changes in MJO activity across coupled simulations with a superparameterized version of the NCARCommunity Earth SystemModel. They find that intraseasonal OLR variance nearly...