1. https://Changing the Oceans - Mr. Parr
Currents

2. Surface currents Frictional drag due to winds
Follow global wind patterns
Circulate between 10s-100s of years
Continents affect surface current patterns
Other factors:
Gravity
Friction
Coriolis Effect

3. Deep/Density Currents
90% of world ocean
“Global Conveyor Belt”
Below pycnocline
Large volumes of seawater
Extremely slow speed – takes 1000s of years
Each ocean basin is similar in deep-ocean circulation

4. The Coriolis Force
1. The deflection of air/water on the surface due to the earth’s rotation
2. Deflection is 45o to the direction of wind
3. Landmasses play a role too

5. Northern Hemisphere Rotation:
Clockwise

6. Southern Hemisphere Rotation
Counterclockwise

7. Eddies Packets of water moving with a circular motion.
Usually small offshoots of currents

8. Gyres Circular flow of water in an ocean.
Usually made of 2-4 currents.

9. Ocean Layers and Vertical Mixing
3 Factors Affecting Ocean Layers
** Pycnocline: where density changes rapidly with depth
** Thermocline: where temperature changes rapidly with depth (cold water is denser)
** Halocline: where salinity changes rapidly with depth

11. Measuring Currents
Current Meter – measures speed and direction of current; must be anchored in place
Drift Bottles – good indicator of start and recovery pts. But not path of travel.
Satellites – best tool for the job overall.

13. Divergence
Divergence (Upwellings) Zones are areas where surface currents are moving away from each other, deep water rises (full of nutrients) so biological productivity is high
Paste it:

14. Convergence
Convergence (Downwellings) Zones are areas where surface currents are moving towards each other, meet and go down taking nutrients away and biological productivity is low.
Paste it:

15. Global Wind Belts