Comparison of Indonesian Throughflow transport observations, Makassar Strait to eastern Indian Ocean

The Pacific to Indian Ocean transport within the passageways of the Indonesian seas (ITF) varies on interannual and longer time scales associated with ENSO, the Asian monsoons and interannual climate variability of the Indian Ocean. Although direct current measurements of the ITF are of limited duration, none long enough to properly describe greater than annual variability of the ITF, observations indicate that the bulk of the ITF passes through Makassar Strait. The repeat expendable bathythermograph (XBT) IX1 section begun in 1983 provides the longest time series of the full ITF introduced into the Indian Ocean between northwest Australia and Java. We find that the surface to 600 dbar Makassar Strait transport, as measured by current meter moorings from December 1996 to July 1998, correlates at r = 0.77 +/- 0.14 with the geostrophic transport constructed from IX1 XBT data for that time interval, with a 98 day lag.