Ch.14.1 Ocean 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.

Oceans, What are they? Stream-like movements in the water!

Surface Currents Stream-like movement of water at or near the surface of the ocean Ex. Gulf Stream

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

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

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 http://www.nasa.gov/audience/forstudents/brainbites/nonflash/bb_home_corioliseffect.html

Currents and Temperature

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 to poles

?Deep Currents? Stream-like movements of ocean water far below the surface. 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)  

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

Upwelling Cold, nutrient-rich water from the deep ocean rises to the surface, replacing warm surface water. Caused by wind Extremely important for organisms