If we now concentrate on the region between stations A and B we see that the two processes (Ekman pumping and westward Rossby wave movement) oppose each other. The long term mean position of the permanent thermocline is achieved through an exact balance in which the upward movement of the thermocline produced by its westward translation is equal in magnitude to the downward vertical velocity produced by Ekman pumping:

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This balance is known as the Sverdrup balance or Sverdrup relationship. It allows us to predict, without recourse to observations, the general shape of the permanent thermocline. See whether you can come to the correct conclusion:

The thermocline is deeper in the west than in the east.

The thermocline is deeper in the east than in the west.

The thermocline can slope down to the west or to the east, but it cannot be horizontal.