Changes in MJO Propagation Characteristics and Regional Variations under a Changing Climate

The Madden-Julian Oscillation (MJO) is a crucial atmospheric phenomenon characterized by large-scale, eastward-propagating disturbances in the tropical atmosphere. It profoundly influences global climate and weather patterns and serves as a key source of predictability for subseasonal forecasts. In particular, the propagation characteristics of the MJO are critical parameters that impacts the timing and intensity of its effects. Variability in these characteristics can alter the MJO’s interaction with other climate components, thereby affecting weather patterns. Therefore, it is essential to investigate the variability of MJO propagation characteristics.

In this study, we aim to examine the changes in propagation characteristics of the MJO, such as propagation speed, across three primary regions: Indian Ocean, Maritime Continent, western Pacific. These changes will be compared between two distinct period (P1: 1979-1998, P2: 2003-2022). Furthermore, we will investigate the mechanisms driving variations in MJO propagation speed within each tropical region and assess potential future changes using reanalysis data and model outputs. By addressing these questions, this study can contribute to improve the predictability and accuracy of climate models in representing the MJO.