Reproducing the Madden-Julian Oscillation (MJO) remains a challenge in many climate models. This study compares MJO simulation skills 17 pairs of Coupled Model Intercomparison Project Phase 5 (CMIP5) and 6 (CMIP6) simulations. Generally, characteristics are better reproduced CMIP6, their inter-model spreads obviously reduced CMIP6. However, most CMIP6 models still underestimate frequency initia...

Abstract This study investigates the intraseasonal change in diurnal cycle of rainfall over Sumatra terms Madden Julian oscillation (MJO) phases. Change peak time mean accumulation (PA), frequency (PF), and intensity (PI) precipitation from Integrated Multi-Satellite Retrievals GPM (IMERG) final run product version 06 data during 2016-2019 was investigated. Data were classified into active (2,3...

The Madden–Julian Oscillation (MJO) is the dominant form of the atmospheric intra-seasonal oscillation, manifested by slow eastward movement (about 5 m s−1) of tropical deep convection. This study investigates the MJO’s impact on equatorial tropospheric ozone (10 N–10 S) in satellite observations and chemical transport model (CTM) simulations. For the satellite observations, we analyze the Trop...

Abstract Recent observations have indicated significant modulation of the Madden Julian Oscillation (MJO) by phase stratospheric Quasi-Biennial (QBO) during boreal winter. Composites MJO show that upper tropospheric ice cloud fraction and water vapor anomalies are generally collocated, an eastward tilt with height in exists. Through radiative transfer calculations, it is shown clouds a stronger...

Prior work has suggested that Rossby wave accumulation in the lower troposphere may be an important mechanism for the development of synoptic-scale disturbances in the western north Pacific in northern summer. This work examines the intraseasonal and interannual variability of wave accumulation by computing the barotropic wave activity flux divergence at 850 hPa for different phases of the Madd...

The Madden–Julian oscillation (MJO) involves pronounced variations in convection and large-scale circulation throughout the tropical troposphere. In addition, the MJO is also related to dynamic and thermodynamic variability near the surface and the upper ocean. This study uses observational data to characterize the changes in surface heat fluxes and sea surface temperature (SST) during the life...

The Madden–Julian oscillation (MJO) is an equatorial planetary-scale circulation system coupled with a multiscale convective complex, and it moves eastward slowly (about 5 m s) with a horizontal quadrupole vortex and vertical rearward-tilted structure. The nature and role of scale interaction (SI) is one of the elusive aspects of the MJO dynamics. Here a prototype theoretical model is formulate...

The multiscale tropical deep convective variability over the Pacific Ocean is examined with the 4-month highresolution deep convection index ( ) derived from satellite imagery. With a systemic view, the complex ITBB phenomenon is described with succinct parameters known as generalized dimensions associated with the correlation structures embedded in the observed time series, with higher-order d...