The throughflow within Ombai Strait

A current meter mooring was deployed for one year in December 1995 in Ombai Strait, one of the deep connections between the Pacific Ocean and the Indian Ocean. Depending on the horizontal extrapolation, the mean transport was estimated to be between 4 and 6 Sv towards the Savu Sea. Succession of intense events of one or two months duration nearly hides the expected annual variability with maximum in August–September. Although the mean currents in the upper 200 m were five times higher than that below, the deep and wide strait section leads to a significant deep transport. Analysis of the hydrological characteristics of the concerned water masses corroborates the circulation given by the current measurements. The east-north-east current in December in the upper layer is thought to be related to the arrival of a Kelvin wave originating in the equatorial Indian Ocean and trapped along the coasts of the Sunda Islands before entering the Savu Sea between Sumba and Flores Islands.