When Whirls Collide 10/30/2015 Record your observations in your science journal. Procedure: 1.Fill a large tub with water 5 cm deep. 2.Add 10 drops of red food coloring to the water at one end of the tub 3.Add 10 drops of blue food coloring to the water at the other end of the tub. 4.Using a pencil, quickly stir the water at one end of the tub in a clockwise direction while your partner stirs the water at the other end in a counterclockwise direction. Stir both ends for 5 s. 5.Draw what you see happening in the tub immediately after you stop stirring. Procedure: 1.Fill a large tub with water 5 cm deep. 2.Add 10 drops of red food coloring to the water at one end of the tub 3.Add 10 drops of blue food coloring to the water at the other end of the tub. 4.Using a pencil, quickly stir the water at one end of the tub in a clockwise direction while your partner stirs the water at the other end in a counterclockwise direction. Stir both ends for 5 s. 5.Draw what you see happening in the tub immediately after you stop stirring.

Think like a Scientist  Ask a question: How will stirring in water in opposite directions affect the water movement.  Conduct Research: water movement, temperature, food coloring, etc.  Form a Hypothesis: If I stir the water in opposite directions, then a whirlpool will form  Test the Hypothesis with a controlled experiment: Independent Variable- The direction of stir Dependent Variable-The movement of the water Constants: speed of stirring, amount of food coloring, etc…  Ask a question: How will stirring in water in opposite directions affect the water movement.  Conduct Research: water movement, temperature, food coloring, etc.  Form a Hypothesis: If I stir the water in opposite directions, then a whirlpool will form  Test the Hypothesis with a controlled experiment: Independent Variable- The direction of stir Dependent Variable-The movement of the water Constants: speed of stirring, amount of food coloring, etc…

Think like a Scientist Continued…  Gather Data-The drawing you created is the data you would use.  Analyze Results-Stirring the water did not cause a whirlpool to form in the center of the tub.  Draw Conclusions-Based on the data I collected, my hypothesis is incorrect.  Communicate Results-I communicated me results by sharing with my classmates.  Gather Data-The drawing you created is the data you would use.  Analyze Results-Stirring the water did not cause a whirlpool to form in the center of the tub.  Draw Conclusions-Based on the data I collected, my hypothesis is incorrect.  Communicate Results-I communicated me results by sharing with my classmates.

Think about it.  Draw what you see happening in the tub immediately after I stop stirring.  How did stirring cause the blue water and the red water interact?  Explain how this activity might relate to how ocean currents interact  Draw what you see happening in the tub immediately after I stop stirring.  How did stirring cause the blue water and the red water interact?  Explain how this activity might relate to how ocean currents interact

Ocean Currents Chapter 5.1 Objective: I CAN.. Investigate the relationship between currents and oceanic temperature differences.

Major Ocean Currents  An Ocean Current is a movement of ocean water that follows a regular pattern  Wind-driven currents are called surface currents  Surface currents carry warm or cold water horizontally across the ocean’s surface  An Ocean Current is a movement of ocean water that follows a regular pattern  Wind-driven currents are called surface currents  Surface currents carry warm or cold water horizontally across the ocean’s surface Currents are influenced by weather, the Earth’s rotation, and the position of the continents.

Major Ocean Currents  Surface currents extend to about 400 m below the surface (less than ¼ mile), and they move as fast as 100 km/day (60 miles)  Earth’s major wind belts, called prevailing winds, influence the formation of ocean currents and the direction they move.  The Gulf Stream is one of the longest surface currents – it transports 25 times more water than all the rivers of the world.  Surface currents extend to about 400 m below the surface (less than ¼ mile), and they move as fast as 100 km/day (60 miles)  Earth’s major wind belts, called prevailing winds, influence the formation of ocean currents and the direction they move.  The Gulf Stream is one of the longest surface currents – it transports 25 times more water than all the rivers of the world.

Surface Currents  Stream-like movements of water that occur at or near the surface of the ocean.  Surface currents are controlled by 3 factors:  Global Winds, the Coriolis effect and Continental Deflections.  Stream-like movements of water that occur at or near the surface of the ocean.  Surface currents are controlled by 3 factors:  Global Winds, the Coriolis effect and Continental Deflections.

Global Winds Have you ever blown gently on a cup of hot chocolate? …Ripples move across the surface caused by a tiny surface current created by your breath. In much the same way that you create ripples, winds that blow across the Earth’s surface create SURFACE CURRENTS in the ocean.

Global Winds o Different winds cause currents to flow in different directions. o Near equator – winds blow ocean east to west o Closer to poles – winds blow ocean west to east o Merchant ships often use these currents to travel more quickly back and forth across the oceans.

Surface Currents

The Coriolis Effect  The Earth’s rotation causes wind and surface currents to move in curved paths rather than in straight lines.

Coriolis Effect  The Coriolis effect also cases fluids to curve to the left in the southern hemisphere, in a counterclockwise direction. The Coriolis Effect is the apparent curving of moving objects from a straight path due to the Earth’s rotation. The Coriolis Effect causes surface currents in the Northern Hemisphere to turn clockwise, and surface currents in the Southern Hemisphere to turn counter- clockwise.

What causes currents to move in curved paths instead of straight lines?

the Coriolis Effect m/channel/none-of-the- above/videos/coriolis- effect/?source=searchvideo (Ball on merry-go-round experiment 2:57)

Continental Deflections  If the Earth’s surface were covered only with water, surface currents would travel freely across the globe in a uniform pattern.  The shapes of continents and other land masses affect the flow and speed of currents.  Currents form small or large loops and move at different speeds, depending on the land masses they contact.  If the Earth’s surface were covered only with water, surface currents would travel freely across the globe in a uniform pattern.  The shapes of continents and other land masses affect the flow and speed of currents.  Currents form small or large loops and move at different speeds, depending on the land masses they contact.

Continental Deflections  Continents rise above sea level over roughly one-third of the Earth’s surface.  When surface currents meet continents, the current deflect, or change direction.  Continents rise above sea level over roughly one-third of the Earth’s surface.  When surface currents meet continents, the current deflect, or change direction.

Taking Temperatures  Currents are also affected by the temperature of the water in which they form.  Warm-water currents begin near the equator and carry warm water to other parts of the ocean.  Cold-water currents begin closer to the poles and carry cool water to other parts of the ocean.  Currents are also affected by the temperature of the water in which they form.  Warm-water currents begin near the equator and carry warm water to other parts of the ocean.  Cold-water currents begin closer to the poles and carry cool water to other parts of the ocean.

Rip Currents  A rip current is a narrow, powerful surface current which flows away from the shore.  It is caused by pressure building up from uneven buildup of water from waves.  They can flow very quickly and can be difficult to detect until you are in one.  A rip current is a narrow, powerful surface current which flows away from the shore.  It is caused by pressure building up from uneven buildup of water from waves.  They can flow very quickly and can be difficult to detect until you are in one.

Surface currents are controlled by what 3 factors?  Global winds  The Coriolis Effect  Continental Deflections  Global winds  The Coriolis Effect  Continental Deflections All three factors work together to form a pattern of surface currents on Earth.

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

Deep Currents Deep currents are not controlled by the wind. WHY? Deep currents form in parts of the ocean where density increases. Density is the amount of matter in a given space, or volume. Density of ocean water is affected by temperature and salinity-- --a measure of the amount of dissolved salts or solids in a liquid.  Both decreasing the temperature of ocean water and increasing the water’s salinity increase the water’s density. Deep currents are not controlled by the wind. WHY? Deep currents form in parts of the ocean where density increases. Density is the amount of matter in a given space, or volume. Density of ocean water is affected by temperature and salinity-- --a measure of the amount of dissolved salts or solids in a liquid.  Both decreasing the temperature of ocean water and increasing the water’s salinity increase the water’s density.

Deep Currents How Deep Currents Form (page 128) Decreasing temperature Increasing salinity through freezing Increasing salinity through evaporation Deep currents form where the density of ocean water increases Water density depends on temperature and salinity.

rthsystem/oceancurrents/ Brainpop: Ocean Currents

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  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

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

om/education/media/ocean-currents- and-climate/?ar_a=1 Great Ocean Conveyor Belt Compares Ocean Conveyor to a roller coaster (2:33)

Upwelling  Upwelling is the vertical movement of water toward the ocean’s surface.  Upwelling occurs when wind blows across the ocean’s surface and pushes water away from an area. Deeper colder water then rises to replace it.  Upwelling is the vertical movement of water toward the ocean’s surface.  Upwelling occurs when wind blows across the ocean’s surface and pushes water away from an area. Deeper colder water then rises to replace it.  Upwelling often occurs along coastlines.  Upwelling brings cold, nutrient-rich water from deep in the ocean to the ocean’s surface.

Video time

Putting it together (1)List the three factors that cause surface currents. (2)List the three factors that cause deep currents. (3)How are surface currents and deep currents different? (1)List the three factors that cause surface currents. (2)List the three factors that cause deep currents. (3)How are surface currents and deep currents different?

3 factors that cause Surface Currents (1) Global winds (2) The Coriolis Effect (3) Continental deflections  These three factors keep surface currents flowing in distinct patterns around the Earth. (1) Global winds (2) The Coriolis Effect (3) Continental deflections  These three factors keep surface currents flowing in distinct patterns around the Earth.

3 factors that cause Deep Currents (1) Decreasing temperature (2) Increasing salinity through freezing (3) Increasing salinity through evaporation (1) Decreasing temperature (2) Increasing salinity through freezing (3) Increasing salinity through evaporation