The Movement of Ocean Water Chapter 14 The Movement of Ocean Water Chap 14, Sect 1 (Currents) Objectives: Describe surface ocean currents. List four factors that control surface ocean currents. Describe deep ocean currents. List three factors that form deep ocean currents.

Ocean Currents……what are they? Stream-like movements in water NASA Ocean Salinity Affecting Currents

Surface Currents……what are they and what controls them? Stream-like movements that occur at or near the surface of the ocean (ex. Gulf Stream off coast of U.S.) The Gulf Stream

Surface currents are controlled by: Four Things: 1. Global winds- winds that blow across the surface, creating ripples

High temp water comes from lower latitudes - 0° Low temp water comes from higher latitudes - 60°+

Surface currents are controlled by: 2. The Coriolis Effect – caused by the Earth’s rotation on its axis, making surface ocean currents, move in curved paths from the poles to the equator and back again Coriolis Effect

3. Continental Deflections – when the land causes the surface ocean currents to change direction due to the lands height above sea-level.

4. Water temperature- cold water from poles displaces rising warm water at equator Warm water from equator is pushed back towards the poles.

Cold Water Currents Cool land near coastal areas that would otherwise be warmer

Currents and Temperature

?Deep Currents? Stream-like movements that occur far below the surface of the ocean. Overall, caused by differences in DENSITY. Density in ocean water is affected by: temperature and salinity differences

3 Factors creating Deep Ocean Currents… 1.  DECREASING TEMPERATURES in water near North and South Poles (cold water is denser thus will sink to the ocean bottom) 2. INCREASING SALINITY thru FREEZING (as water freezes, dissolved solids are squeezed out, increasing the salinity thus water will be denser and will sink to the ocean bottom)

3. INCREASING SALINITY thru EVAPORATION (more common in warmer climates where evaporation leaves dissolved solids behind, increasing salinity creating denser water which will sink to the ocean bottom)  Deep Currents Video

Formation of Deep Ocean Currents

In Summary: Part A The Gulf Stream (a surface current) carries warm water from the Gulf to the North Atlantic Part B Now, the air above this warm surface current is allowed to gain thermal energy by conduction

As a Result, Part C There is a mild climate in England

Currents and Temperature