This research was supported by the National Science Foundation through Grant ATM-9416701. Comments by Dr. Steven Feldstein, Prof. Peter Bannon, and Prof. John Clark on the early version of this manuscript are greatly appreciated. Thanks are also due to Dr. Gareth Williams for suggesting the use of better terminologies and for pointing out his GCM calculations (Williams 1988) that hint at the existence of the interjet disturbances. Comments by an anonymous reviewer are also appreciated.
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