THE EFFECTS OF WINDS OVER A BAROTROPIC RETROGRADE SLOPE CURRENT

A barotropic, retrograde slope jet, with its cyclonic flank up-slope, is subjected to persistent head winds or tail winds, or variable winds associated with the passage of swiftly moving cyclones. A head wind p ushes the current jet up-slope and increases its speed against the win d. Likewise, a tail wind reduces its speed. Cyclones leave a trail of inertial oscillations over a deep, quiescent ocean, but when they pass over a retrograde slope current, the inertial oscillations are disper sed, and they excite topographic Rossby waves which propagate upstream . Using an example from the Barents Sea, it is shown numerically that a head wind can intensify the slope current more than 30% and a typica l Polar low can excite significant topographic Rossby waves with a per iod of 36 hours. (C) 1998 Elsevier Science Ltd. All rights reserved.