What causes
ocean currents?
Ocean currents are created when
ocean water is driven by the winds,
by the earth's rotation, and by
differences in temperature and
salinity. Most currents in the top
layers of the ocean are created by
the wind pushing the surface of the
water.
Materials: shallow baking pan,
pepper, straws, a friend
- Fill the baking pan with an
inch of water.
- Sprinkle some black pepper
in one corner of the pan.
- You and your friend stand on
opposite sides of the pan.
- Each of you aim your straw
along the side of the pan to
your left.
- Gently blow through the
straws across the top of the
water and observe the motion of
the pepper. This clockwise
motion of the pepper is the same
basic motion of ocean currents
in the Northern Hemisphere.
These roughly circular current
flows are called gyres.
