Ocean currents in the northern and southern hemispheres turn in opposite directions. This is due to the Coriolis effect.

Here's how it works:

* The Coriolis effect: The Earth's rotation causes moving objects (like water in ocean currents) to be deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.

* Northern Hemisphere: Currents in the Northern Hemisphere are deflected to the right, causing them to turn clockwise.

* Southern Hemisphere: Currents in the Southern Hemisphere are deflected to the left, causing them to turn counterclockwise.

This pattern of rotation is crucial for understanding global ocean circulation and its impact on weather patterns, climate, and the distribution of marine life.