The Onset of the Monsoon over the Bay of Bengal:The Observed Common Features for 2008-2011
The Onset of the Monsoon over the Bay of Bengal: The Observed Common Features for 2008–2011

In situ buoy observation data spanning four years(2008-2011) were collected and used to perform a composite analysis of the monsoon onset process in the Bay of Bengal(BoB).The sea surface temperature(SST) in the central BoB increases dramatically during the monsoon transition period and reaches its annual maximum just before the onset of the monsoon.This process is illustrated by the northward-propagating deep convection phase of the intraseasonal oscillation and the establishment of a steady southwest wind.It is argued that the SST peak plays a potential role in triggering the onset of the monsoon in the BoB and its vicinity.The general picture of the BoB monsoon onset summarized here reveals the possibility of regional land-ocean-atmosphere interaction.This possibility deserves further examination.