The upwelling evolution as displayed in Figs. 1 and 2 corre - sponds very well to the SE monsoon cycle. In the SE monsoon easterly alongshore wind (Fig. 3) in the southeastern tropical Indian Ocean starts to intensify. In June, alongshore wind is further intensified causing an upwelling and shoaling of the thermocline off the east Java coast. Current meter data [Fig. 2, Sprintall et al., 1999] from the Cilacap mooring (in south central Java) showed an eastward flow associated with semiannual coastally trapped Kelvin wave in May 1997 and a westward flow due to SE monsoon wind