13.1 Teacher Notes Ocean Currents

Waves are on the surface of water Currents are below the surface What is the difference between a current and a wave? Waves are on the surface of water (i.e. - ocean waves at a beach) Currents are below the surface (i.e. – EAC – East Australian Current)

surface currents – currents near the surface of the ocean (warm and/or cold currents) 3 things can change the direction of surface currents: continental deflections – currents change direction because they hit a continent global winds – global winds can blow a current a different direction Coriolis effect – the Earth rotating changes the direction of winds and currents (they do not go straight because the Earth is turning in circles) (i.e. – throwing a ball onto a spinning merry-go-round)

deep currents – currents far below the surface of the ocean (all cold currents) Deep currents travel along the ocean floor convection currents – heat rises, cool sinks (cool sinks because it is denser – heavier) Surface currents and deep currents are linked in the ocean, they switch places due to a difference in temperature The surface currents are warm because of heat from the sun The deep currents are cold because they are so far away from the sun