William E. Johns

Steve Murray

/ LSU

The comprehensive Bab el Mandeb experiment at the southern end of the Red Sea during 1995-1996 involving moored ADCPs and T-S sensors (Fig. 1) revealed the annual cycle of the exchange in a detail that had not been available before (Fig. 2). The inflow and outflow transports of the exchange flows were well resolved and showed a very repeatable transition between the winter two-layer regime and summer three layer regime over the 17 months of continuous observation (Fig. 3). The changing inflow/outflow conditions were clearly reflected in the salinity variations in the strait, which documented for the first time the extent and timing of the summertime intrusion of fresh Gulf of Aden thermocline water into the Red Sea. The annual mean outflow of Red Sea deep water through the strait was estimated to be 0.37 Sv, with maximum exchange reaching 0.7 Sv in February and average summer outflow of ~0.05 Sv.

Publications:

Murray, S. P., and W. Johns, 1997, Direct observations of seasonal exchange through the Bab el Mandeb strait, Geophys. Res. Let., 24, 2557-2560.

Pratt, L.J., W. Johns, S.P. Murray and K. Katsumata, 1999, Hydraulic interpretation of direct velocity measurements in the Bab al Mandab. J. Phys. Oceanogr. (in press).

Pratt, L.J., H. Deese, S.P. Murray and W. Johns, 1999, Continuous dynamical modes of the Bab al Mandab and their hydraulic interpretation. J. Phys. Oceanogr. (submitted).

For further information, please contact:
Bill Johns (305) 361-4054