Increase in Intraseasonal Rainfall Driven by the Arabian Sea Warming in Recent Decades

Intraseasonal oscillation (ISO) is the dominant variability during Indian summer monsoon (ISM). In this study, it found that ISOs accompanying intraseasonal rainfall are substantially enhanced over northeastern Arabian Sea (AS) in past three decades. The rise agrees with variation moisture loading. strengthening of wind convergence planetary boundary layer (PBL) triggers changes vertical velocity, intensifying advection background by which contributes most to intensified supply AS. addition, faster warming AS and increasing cyclonic vorticity associated poleward movement mean low-level jet responsible for trend PBL convergence. This recent has contributed extremes central-western parts subcontinent.