摘要：In situ buoy observation data spanning four years (2008–2011) were used to demonstrate the year-to-year variations of the monsoon onset processes in the Bay of Bengal (BoB). A significant early (late) mon-soon onset event in 2009 (2010) was analyzed in detail. It is found that the year-to-year variations of monsoon onset can be attributed to either the interannual variability in the BoB SST or the irregular activities of the intra-seasonal oscillation (ISO). This finding raises concern over the potential difficulties in simulating or predicting the mon-soon onset in the BoB region. This uncertainty largely comes from the unsatisfactory model behavior at the intra-seasonal time scale.
关键词：monsoon onset; interannual variations; Bay of Bengal; SST
