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A significant component of the Indonesian throughflow, apparently about 25%, passes through the Lombok Strait. Direct observations in 1985 reported a ~2 Sv annual average, with an annual cycle of amplitude ~2 Sv. There are also significant fluctuations in this Wansport in the 0.01-0.1 cl• frequency band. Shallow pressure gauge data (sea level) inside the strait during the current meter observations were of limited use in explaining the large fluctuations in currents. Sea level data at Cilacap, 720 km west (upcoas0, however, overlap the current observations for 5 months and correlate exceedingly well (r = 0.87) with the observations inside the slrait at these frequencies. These sea level oscillations in the Indian Ocean force fluctuations in the Lombok throughflow that reach 50-70 cm/s, equivalent to 2-3 $v. Lagged regression analysis indicates Cilacap sea level leads Lombok currents by 1-2 days, suggesting a low-frequency, progressive wave. Simultaneous data in 1989 from four stations extending from the near-equatorial station at Padang at løS to Benoa in the Lombok Strait (2000 km downcoas0 clearly show the persistent propagation of low-frequency waves of 20-to 40-cm range along this coast. Lagged correlation on station pairs indicates a phase speed consistant with coastally trapped internal Kelvin waves. We speculate that farther eastward progression of these waves to the Timor Passage of Ombai Strait will further modulate the throughflow. The forcing of these waves is not yet identified, but it appears likely that intmseasonal oscillations in the equatorial Indian • winds, as demonstrated by Enfield [1987] for the Pacific, are a probable mechanism. Improved wind data quality in 1991 due to the assimilation of satellite data (special sensor microwave/imager) will allow investigation of remote forcing on more recent data sets. Recent modeling studies also agree on a significant (10-20 Sv) Pacific-to-Indian transport. The multilayer global model of Semtner and Chervin [1988] indicated a mean 1T of 15-18 Sv; the global Sverdrup model of Godfrey [1989] predicted 16+4 Sv; and the reduced gravity global model of Kindle eta/. [1989] exhibited a mean for 1980-1987 of about 5 Sv, with a seasonal signal of amplitude 4 Sv. A recent basin-scale model study [lnoue and Welsh, 1993] forced by monthly mean climatological winds predicted a total IT ranging from 0.5 Sv toward the Pacific up to 18.1 Sv toward the Indian Ocean in July-October, with a yearly mean of ~10 Sv. This model indicates that the Lombok Strait (Figure 1) carries nearly 40% of the total IT, with the balance passing through the major passages bracketing Timor. While the importance of Lombok Strait is probably overestimated in this model, it is clear that it is a significant conduit for the IT. These modeling studies are generally consistent with results from the observational front. Drifters [Lukas eta/., 1991], hydrographic properties [Ffield and Gordon, 1992], and modeling results [Kindle eta/., 1989; Inoue and Welsh, 1993] identify the Makassar Strait as th...

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