1. The question of what "drives" the ocean has led to some confusion and disagreement in the scientific literature, in part because the term "drive" means different things in different contexts. A car is driven (i.e., controlled) by a driver, usually human, but the car wheels are driven (i.e., powered) by the engine. Unfortunately, in science, too, the word is sometimes used to mean powered by, and sometimes controlled. To avoid the word completely would be tilting at windmills, but we try to use it only in contexts in which its meaning is unambiguous.
2. The torques that we refer to in this section are local effects, enabling a parcel to spin like a propellor, albeit thousands of times slower. Technically, they are the curls of (i.e, V X) the forces—"force-curls"—rather than the force times the distance from a fulcrum. The pressure gradient force does not provide a torque; its curl is zero: V X Vp = 0.
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