2023 journal article

The Impact of the Madden-Julian Oscillation on the Formation of the Arabian Sea Monsoon Onset Vortex

GEOPHYSICAL RESEARCH LETTERS, 50(17).

By: S. Dhavale n & A. Aiyyer n

author keywords: monsoon onset vortex; Madden-Julian Oscillation; Indian summer monsoon; Arabian Sea; genesis potential index
UN Sustainable Development Goal Categories
13. Climate Action (Web of Science)
14. Life Below Water (OpenAlex)
Source: Web Of Science
Added: September 11, 2023

AbstractDuring certain years, a synoptic scale vortex called the monsoon onset vortex (MOV) forms within the northward advancing zone of precipitating convection over the Arabian Sea. The MOV does not form each year and the reason is unclear. Since the Madden‐Julian Oscillation (MJO) is known to modulate convection and tropical cyclones in the tropics, we examined its role in the formation of the MOV. While the convective and transition phases of the MJO do not always lead to MOV formation, the suppressed phase of the MJO hinders the formation of the MOV more consistently. This asymmetric relationship between the MJO and MOV can be partially explained by the modulation of the large‐scale environment, measured by a tropical cyclone genesis index. It also suggests that the Arabian Sea is generally near a critical state that is favorable for MOV formation during the monsoon onset period.