Movement of Ocean Water Part 1:Currents Part 2: Waves Part 3: Tides

Imagine… You are stranded on a desert island. You stuff a distress message into a bottle and throw it into the ocean. Is there any way to predict where your bottle may land? Actually, there is a way to predict where the bottle will end up. Ocean water contains stream like movements of water called OCEAN CURRENTS.

Movement of Ocean Water Part 1: Currents

Activating Strategy: Watch the video below then answer the questions. The E.A.C. Where is this event happening? What causes the condition shown in the video? What do you think is the importance of the condition shown? Instructional Approach(s): The teacher should show the video clip while the students answer the two questions. The teacher may want to do this as a Think, Pair, Share. The students would “think” and answer the two questions on their own while watching the video. Then the teacher should spend no more than 2-3 minutes doing “Pair and Share”

What do currents and climate have to do with each other? the ocean is the heated blanket of the earth. Ocean currents carry the heat to different locations around the Earth. The heat is released into the atmosphere creating wind, through convection currents (Hot air rises, cold air falls). This creates different climates in different parts of the Earth.

Ocean currents Ocean Currents: a movement of ocean water that follows a regular pattern Surface currents Deep Currents Crash Course: Currents

Surface Currents and Deep currents Surface currents: a horizontal movement of ocean water that is caused by wind and that occurs at or near the ocean's surface Through global winds, water in the ocean flows in different directions. Near the equator, the winds blow ocean water east to west, but closer to the poles, ocean water is blown west to east. Deep currents: a stream like movement of ocean water far below the surface Not caused by winds Caused by density (the amount of matter in a given space, or volume Decrease in temperature and increase in salinity affects the density of ocean water

Ocean Currents: Surface Currents Surface winds and surface currents are affected by the rotation of the Earth (the Coriolis Effect) Coriolis Effect Demonstration Because Earth rotates toward the east, winds appear to curve to the right in the northern hemisphere and to the left in the southern hemisphere So, currents north of the equator turn to the right and currents south of the equator turn to the left Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes.

Causes of Currents: Coriolis Effect The Coriolis Effect: the apparent curving of the path of a moving object from an otherwise straight path due to the Earth’s rotation Coriolis Effect

Ocean Currents: Surface Currents Surface currents move water horizontally – parallel to Earth’s surface Surface currents are powered by wind The wind forces the ocean to move in huge, circular patterns There are warm surface currents and cold surface currents Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes.

Ocean Currents: Surface Currents Instructional Approach(s): The teacher should use the diagram to illustrate surface currents.

Surface Currents Review The ocean absorbs, stores, and moves the sun’s heat (energy) Surface currents transport this energy all over the world Surface currents move warmer water into cooler regions and return cooler water to the warmer regions (tropics) Currents can have a cooling effect on an area’s climate or a warming effect on an area’s climate As warm water flows from the equator, heat is released into the atmosphere and the air is warmed. Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes.

Causes of Currents: Continental Deflection Continental Deflection: when water currents meet the continents, the current is deflected (change direction) Gulf Stream Demonstration Video

Temperature and Salinity Affect the Density of Ocean Water. The video reminded us that the masses of water are moved by wind, but what did they say was the primary cause of ocean currents? Different densities are responsible for ocean currents. What factors did we learn influence ocean water’s density? Temperature and Salinity Affect the Density of Ocean Water. Instructional Approach(s): The teacher should present the information on the slide.

Temperature, Salinity and Density review Ocean depth increases Density increases Temperature increases Salinity increases Salinity increases Density increases Temperature decreases Density decreases Instructional Approach(s): The teacher should review the information on the slide while the students record the important information on their notes. Temperature decreases because cold water is more dense and sinks

Deep Current What causes deep currents to move if the wind doesn’t have an effect on it? Water density moves the water. Cold water is more dense and it sinks and moves. Warm water is less dense and it rises. Note: surface currents travel much faster than deep ocean currents.

Density & Currents Deep in the ocean, waters circulate not because of wind but because of density differences. A density current forms when a mass of seawater becomes more dense than the surrounding water. More dense seawater sinks beneath less dense seawater. Density currents circulate ocean water slowly. Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes.

Density Currents Instructional Approach(s): The teacher should present the information on the slide while the students record the important information on their notes.

Density Currents Instructional Approach(s): The teacher should use the diagram to illustrate density currents.

Density Currents Instructional Approach(s): The teacher should use the diagram to illustrate surface currents and density currents.

Temperature Currents Explained Warm-water currents and climate: warmer climates in coastal areas that would otherwise be much cooler Gulf stream carries warm water from the Tropics to the North Atlantic Ocean Cold-water currents and climate: colder climates in areas that would otherwise be much warmer. California Current carries cold water from the North Pacific Ocean southward to Mexico

Upwelling Upwelling: the movement of deep, cold, and nutrient-rich water to the surface Nutrients brought to the surface of the ocean support the growth of phytoplankton and zooplankton, that in turn supports other organisms such as fish and seabirds

El Nino/la Nina El Nino: a change in the water temperature in the Pacific Ocean that produces a warm current La Nina: a change in the eastern Pacific Ocean in which the surface water temperature becomes unusually cool El Nino/La Nina Video

Ocean Currents Song https://www.youtube.com/watch?v=NsdH_NRM-CU Instructional Approach(s): The teacher should show the ocean current song video to reinforce the concept of ocean currents

Movement of Ocean Water Part 2: Waves

Waves & Currents Video Study Jams Video Instructional Approach(s): The teacher should show the video to reinforce the concept of waves and currents

Waves Have you ever seen a surfer riding waves? Did you ever wonder where the waves come from? And why are some waves big, while others are small? We all know what waves look like, but do you know how they are formed? Wind Earthquakes Landslides Weather surges

Waves are made up of two main parts: Anatomy of a Wave Waves are made up of two main parts: Crests Troughs

Anatomy of a Wave Crests: the highest part of a wave Trough: the lowest point of a wave

Anatomy of a Wave Wavelength: the distance between two adjacent wave crests or wave troughs Wave height: the vertical distance between the crest and trough of a wave Wave period: the time between the passage of two wave crests at a fixed point

Wave Movement The ocean has an optical illusion… As you sit and watch ocean waves, it appears the water is moving in and out. However, waves form as wind blows across the water’s surface and transfers energy to the water. As energy moves through the water, so do the waves. The water itself stays behind, rising and falling in circular movements. Wave Movement Demonstration

To calculate wave speed, scientist use wavelength and wave period. Wave Movement Waves not only come in different sizes but also travel at different speeds. To calculate wave speed, scientist use wavelength and wave period. Wavelength (m) Wave period (s) = wave speed (m/s)

Waves can be formed by other mechanisms besides wind. Types of Waves Waves can be formed by other mechanisms besides wind. Deep water waves: waves that move in water deeper than one-half their wavelength. When waves reach water that is shallower than their wavelength, they begin to interact with the ocean floor. These waves become shallow water waves. As the waves move from deep water, the water particles slow down and build up. This change forces more water between wave crests and increases wave height. Gravity causes the wave crest down, which causes them to crash into the ocean floor (breakers). The are where the waves begin to break is called the breaker zone. Waves continue to break as they move from the breaker zone to the shore. The area between the breaker zone and the shore is called the surf.

Swells: rolling waves that move steadily across the ocean Open-Ocean Waves Whitecaps: white, foaming waves with very steep crests that break in the open ocean before the waves get close to the shore Form during stormy weather Usually short lived Swells: rolling waves that move steadily across the ocean Have longer wavelengths that whitecaps Can travel for thousands of kilometers

Open-Ocean Waves

Tsunami Tsunami: waves that form when a large volume of ocean water is suddenly moved up or down Earthquake Volcanic eruptions Landslides Underwater explosions Meteorite or comet impact

https://www.youtube.com/watch?v=bBa 9bVYKLP0 Storm Surges Storm surge: a local rise in sea level near the shore that is caused by strong winds from a storm, such as those from a hurricane https://www.youtube.com/watch?v=bBa 9bVYKLP0

Movement of Ocean Water Part 3: Tides

Tides are daily changes in the level of the ocean water Both the Sun and the Moon influence the level of tides

Why Tides Happen The moon’s Gravity pulls on every particle on Earth. However, the Moon’s gravity doesn’t pull on every particle with the same strength. The part of Earth that faces the moon is pulled toward the moon with greatest force. The water on the side of the Earth that faces the moon bulges toward the moon. * The difference in the moon’s pull is more noticeable in liquids than in solids because liquids can move more easily.

High Tides/low tides The bulges that form in the oceans because of the moon’s pull are called High Tides. The water in-between high tides are called Low tides. The Earth Rotates on its axis, so high tides happen in different places on Earth at different times of day. Because Earth’s rotation is so predictable, the tides are predictable. Many places experience two high tides and two low tides per day. Brief Tidal Overview

Spring Tide Tides that have the largest daily tidal range The sun, the Earth, and the Moon are aligned New Moon and Full Moon Phases (every 14 days)

Neap Tide Tides that have the smallest daily tidal range The sun, Earth, and the Moon form a 900 angle During first-quarter and third-quarter phases of the moon

Tides Crash Couse in Tides