3. Why do we need to understand how the Ocean Moves?
weather
climate
natural disasters:
***we LOVE Earth***
hurricanes, tsunamis, tornadoes, earthquakes,
volcanoes, sinkholes, droughts, heat, waves,
wildfires, floods, blizzards, avalanches
4. Ocean Circulation
- Stratification
- Rotation of the Earth
- Wind
- Continental Boundaries
These factors cause
-Small Scale Ocean Phenomena
-Medium Scale Ocean Phenomena
-Large Scale Ocean Phenomena
8. Global Winds
∗ Coriolis Force
∗ Gulf Stream
Westerlies:
∗ Lie between the Northern
and Southern Hemisphere
∗ Blows from west to east
along the equator
∗ Highly variable and
unsteady winds
∗ Part of hurricanes,
tsunamis, monsoons, etc.
Frequent changes to the
weather:
∗ Mid-latitude storms
∗ Wintertime changes
Trade:
∗Travels from east to west
∗ Lie on both sides of the
equator which:
∗ Gives out steady wind flow
∗ Ocean waves are very
steady around these areas
∗ Sail and fishing boats
depend on the airflow to get
to nearby coastal areas
safely
9. Thermohaline
Circulation
-Large Scale Ocean Phenomena
-Deep and shallow currents create the well known "Great
Ocean Conveyor Belt"
-Regulates our climate
-The movement of large quantities of water allow for the
transportation of nutrients and heat
-It is the overall circulation of the ocean, if it shuts down
everything would collapse
10. The Experiment
-Lab simulation of the differences in water temperature
-The lab was conducted by placing ice packs on one end of
the dish and placing a lamp on the on the other end.
-The water had to stand for 20-30 minutes and then colored
dye was added.
-The warm water(red/equator) rose above the colder
water(blue/North Pole)
11. Western Boundary Currents
Causes
1. Wind
2. Rotation of the earth
3. Continental boundaries
Hypothesis
The Western Boundaries Currents (WBCs) need all the three factors to develop
the circulation pattern observed by satellites.
Methods
-Set up laboratory scale experiment that mimic Western Boundary Currents
-Set up computational experiments that mimic Western Boundary Currents
12. Lab Experiment
Materials
-Big plastic tank
(continental
boundaries)
- Water (ocean)
- Slope (spherical
rotation)
- Two little pillars
- Fans (winds)
- Red and blue dye
- Turntable (rotation of
earth)
- Camera
Procedure
-Set up the two little pillars
-Put in the slope
-Fill the tank with water
-Adjust the fans (North and South side of
the box) SP=West ;NP=East (to mimic
the winds)
-Set up the camera
-Begin the counterclockwise rotation of
the tank, like the Earth
-Let it spin for 20-30 minutes
-When ready, add the red & blue dyes
(red = southwest & blue = northeast )
Trials
Trial A - All factors
Trial B - No wind (no fans)
Trial C - No spherical
rotation (no slope)
Trial D - No rotation of Earth
(no rotation of tank)
14. Computational Experiment :MATLAB
The 5 Factors
1. Local Changes
2. Convection
3. Coriolis
4. Wind
5. Diffusion/ smoothing/ disappearing effect
Trials
Case 1 = All Terms
Case 2 = No Convection
Case 3 = No Coriolis
Case 4 = No Wind
Case 5 = No Diffusion
Experiment
- Using a coding program MATLAB we were able to view different
simulations on the computer
- Equations used in mechanical engineering are long and complex
that they can easily be solved using a software such as MATLAB
- The equation we plugged in was the Barotropic Vorticity Equation
- Vorticity: a measure of how much the fluid spins
- We were able to make videos of how the western boundary
currents look from satellites
Look at video
15. Why do we care?
-Melting of ice caps slows thermohaline
circulation causing extreme climate change
-The ocean’s temperature increase and
sea level rise will cause severe hurricanes
