Schneider, N., S. Venzke, A. J. Miller, D. W. Pierce, T. P. Barnett,
C. Deser and M. Latif, 1999:
Pacific thermocline bridge revisited
Geophysical Research Letters, 26, 1329-1332.
Abstract.
The coupling on decadal time scales of the midlatitude and tropical Pacific via an oceanic 'bridge' in the thermocline
is investigated using ocean general circulation model hindcasts and a coupled ocean atmosphere model. Results
indicate that in the tropics decadal anomalies of isopycnal depth are forced by Ekman pumping and are largely
independent of the arrival of subducted anomalies in the thermocline that originate in the mid-latitudes of either
hemisphere. In the coupled model, temperature anomalies on isopycnals show little coupling from the tropics to the
northern hemisphere, but are lag correlated between southern hemisphere mid- and low-latitudes. However, anomaly
magnitudes on the equator are small. These results suggest that the oceanic 'bridge' to the northern hemisphere
explains only a small part of the observed decadal variance in the equatorial Pacific. Coupling to the southern
mid-latitudes via temperature anomalies on isopycnals remains an intriguing possibility.
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