The seasonal variation of the throughflow predicted by “Godfrey's island rule” (Godfrey, 1989) with the ERS wind stress is also shown in Figure 2 (dotted line). The island rule transport has a mean value of 10.8 Sv and the seasonal range of 7.6 Sv, which are similar to the results of IR case. However, since the island rule does not take into account the semiannual signal caused by the variations in the Indian Ocean, the local minimum in May is not predicted well in the island rule transport.
Figure 2: Seasonal variations of the throughflow transport simulated in the model for SR (dashed line) and for IR (solid line). The transport estimated with “Godfrey's island rule” is also shown (dotted line).
3.2. Interannual Variations
The simulated interannual variations and the interannual anomalies from the climatological mean seasonal cycle from July 1992 to June 1997 are shown in Figure 3. The large throughflow is observed during the period from the middle of 1993 through 1995, while the transport is almost zero in 1997 (Fig. 3a). The peak-to-peak amplitude exceeds 25 Sv with the maximum transport of 23 Sv in September 1995 and the minimum of 5 Sv to the Pacific Ocean in June 1997. The simulated large transport during 1994/95 period is consistent with the observational evidences (Wijffels et al. 1996)and other numerical simulations (e.g., Potenra et al., 1997).
