Climate and Ocean Currents

2. Major Ocean Currents
 An Ocean Current is a
large volume of water
flowing through the
ocean.
 Types of Currents:
Surface Currents Caused by Wind Warmer Currents
Deep Currents
Caused by Density
Differences
Colder Currents

4. Surface Currents
 Surface currents extend to
about 400 m below the
surface, and they move as fast
as 100 km/day.
 Earth’s major wind belts
influence the formation of
ocean currents and the
direction they move.
 Surface Current Patterns
 East Coast – warm current
 West Coast – cold current

5. Surface Currents Animation
 http://www.classzone.com/books/earth_science/terc/
content/visualizations/es2401/es2401page01.cfm

7. Coriolis Effect
• Earth’s rotation
makes the wind
curve, as a result,
the ocean’s surface
currents curve.
Coriolis
Effect
Curve to the LEFT in
the SOUTHERN
HEMISPHERE.
Curve to the RIGHT
in the NORTHERN
HEMISPHERE.
 Currents form small or
large loops and move
at different speeds,
depending on the land
masses they contact.

9. Effects on Climate
 Warm-water currents
and cold-water currents
affect weather and
climate in different
ways
 Regions near warm-
water currents are often
warmer and wetter than
regions near cold-water
currents

10. Effects on Climate
 The Gulf Stream is a warm-water current that affects
coastal areas of the southwestern United States by
transferring lots of thermal energy and moisture to the
surrounding air.
 The cold California
Current affects
coastal areas of the
southwestern United
States.

11. Effects on Climate
 https://www.youtube.com/
watch?v=zAGr4Mfbg-E

12. Effects on Climate
 Examine the link and animation below:
 http://www.classzone.com/books/earth_science/terc/
content/investigations/es2403/es2403page01.cfm?cha
pter_no=investigation

17. Upwelling
Upwelling is movement of
cold water upward from the
deep ocean often occurring
along coastlines.
1. Wind blows across the ocean’s surface
2. Water is pushed water away from an area.
3. Deeper colder water then rises to replace it,
bringing cold, nutrient-rich water from
deep in the ocean to the ocean’s surface.

19. Upwelling animation
 http://www.classzone.com/books/earth_science/terc/
content/visualizations/es2405/es2405page01.cfm?chap
ter_no=visualization
 Examples of Upwelling – El Nino/La Nina:
http://www.classzone.com/books/earth_science/terc/
content/visualizations/es2405/es2405page01.cfm?chap
ter_no=visualization

21. Deep Density-Salinity Currents
 Density Currents are a type of vertical current that
carries water from the surface to deeper parts of the
ocean.
 Density Currents are
caused by changes in
density rather than
wind (SALINITY)
 Density currents
circulate thermal
energy, nutrients and
gases throughout the
world.

22. Deep Water Density Currents

23. Great Ocean Conveyor Belt
 The Great Ocean conveyor Belt is the name for a model of
the large system of ocean currents that affects weather and
climate by circulating thermal energy around Earth.
 In this model, high salinity water cools and sinks in the
North Atlantic, and deep water returns to the surface in the
Indian and Pacific Oceans through upwelling

25. Great Ocean Conveyor Belt
 Scientists estimate that the Great Ocean Conveyor Belt
model takes about 1,000 years to complete a cycle.