The Oceans

Pacific Ocean Pacific Ocean: The Pacific Ocean is the biggest ocean of the world and covers more than 30% of the Earth's surface. The ring of fire is located in the Pacific Ocean.

Atlantic Ocean Atlantic Ocean: The Atlantic is the second biggest ocean in the world and is between the continents of America and Europe and Africa. The Atlantic Ocean is about half the size of the Pacific Ocean and covers roughly 20% of the Earth's surface. However it is growing in size as it is spreading along the Mid-Atlantic Coasts. The Mid-Atlantic Ridge is the longest mountain range on Earth. It spreads from Iceland to Antarctica beneath the Atlantic.

Indian Ocean Indian Ocean: The Indian Ocean is located between Africa, Australia and Asia. The waters of the Indian Ocean provide the largest breeding grounds of the world for humpback whales.

Arctic Ocean Arctic Ocean: The Arctic Ocean is located around the North Pole across the Arctic Circle. There are many polar bears living on the Arctic ice.

Southern Ocean Southern Ocean: The Southern Ocean is located around the South Pole across the Antarctic Circle in the Southern Hemisphere off Antarctica.

TIDES

Tides Tides are the daily rise (high tide) and fall (low tide) of water along coastlines.

Gravity and Tides: Tides are caused by the gravitational interaction between the Earth, the moon and, the sun. Gravity is the force where one object pulls on another object. The pull of the moon on Earth’s waters causes a tidal bulge on the side of the Earth facing moon. The opposite side has the least amount of force pulling on its water, so there is a bulge there as well.

The Daily Tidal Cycle: The rotation of the Earth through these bulges causes most coastlines to experience two high tides and two low tides each day. The difference in water level between high tides and low tides varies from place to place.

The Monthly Tidal Cycle: The position of the sun, moon, and Earth in relation to one another affects tidal levels on a monthly basis.

Spring tides occur during full and new moons, when the sun, moon, and Earth are arranged in a straight line. Spring tides have the largest difference between high and low tides.

Neap tides occur during first and third quarter moons, when the sun, Earth, and moon are arranged in a ninety degree angle to one another. Neap tides have the smallest difference between high and low tides.

Regular Tide Description: Pull of the moon on Earth’s waters causes a bulge on the side of the Earth facing the moon and the opposite side. As long as it is not lined up with the sun or at a ninety degree angle it is a regular tide.

Write a description for each tide and draw the positions of the moon for a Spring Tide, Neap Tide and a Regular Tide. Spring Tide Description: occur during full and new moons, when the sun, moon, and Earth are arranged in a straight line. Neap Tide Description: occur during first and third quarter moons, when the sun, Earth, and moon are arranged in a ninety degree angle to one another. Regular Tide Description: pull of the moon on Earth’s waters causes a bulge on the side of the Earth facing the moon and the opposite side. As long as it is not lined up with the sun or at a ninety degree angle it is regular. Earth Earth Earth Earth Earth Earth

Write a description for each tide and draw the positions of the moon for a Spring Tide, Neap Tide and a Regular Tide. Spring Tide Description: occur during full and new moons, when the sun, moon, and Earth are arranged in a straight line. Neap Tide Description: occur during first and third quarter moons, when the sun, Earth, and moon are arranged in a ninety degree angle to one another. Regular Tide Description: pull of the moon on Earth’s waters causes a bulge on the side of the Earth facing the moon and the opposite side. As long as it is not lined up with the sun or at a ninety degree angle it is regular. Earth Earth Earth Earth Earth Earth

Write a description for each tide and draw the positions of the moon for a Spring Tide, Neap Tide and a Regular Tide. Spring Tide Description: occur during full and new moons, when the sun, moon, and Earth are arranged in a straight line. Neap Tide Description: occur during first and third quarter moons, when the sun, Earth, and moon are arranged in a ninety degree angle to one another. Regular Tide Description: pull of the moon on Earth’s waters causes a bulge on the side of the Earth facing the moon and the opposite side. As long as it is not lined up with the sun or at a ninety degree angle it is regular. Earth Earth Earth Earth Earth Earth

Write a description for each tide and draw the positions of the moon for a Spring Tide, Neap Tide and a Regular Tide. Spring Tide Description: occur during full and new moons, when the sun, moon, and Earth are arranged in a straight line. Neap Tide Description: occur during first and third quarter moons, when the sun, Earth, and moon are arranged in a ninety degree angle to one another. Regular Tide Description: pull of the moon on Earth’s waters causes a bulge on the side of the Earth facing the moon and the opposite side. As long as it is not lined up with the sun or at a ninety degree angle it is regular. L L H H Earth H H Earth L L H H L L Earth L L Earth H H H L L H Earth Earth H L L H

The driving energy source for heating of Earth and circulation in Earth’s atmosphere comes from the Sun and is known as solar energy. There are three ways thermal energy can be transferred, radiation, conduction and convection.

Radiation Radiation is the solar energy from the sun warms the surface of the earth, however different materials heat at different rates, which causes the earth’s surface to heat unevenly. Uneven heating causes air to move.

Conduction As the surface of the earth is heated, it in turn heats the air which is touching the earth’s surface. This type of heat transfer is called conduction. Conduction is heat transfer through direct contact.

Convection The warm air that touches the surface becomes warmer, less dense and rises. This is the third type of heat transfer known as convection. Convection is the type of heat transfer that occurs with the movement of liquids and gases through convection currents. Solar radiation warms Earth's surface. The ground warms the air that touches it through conduction. Energy moves upward through convection as warm air is pushed upward by cooler, denser air.

Winds

Local Winds: Small-scale convection currents arise from uneven heating on a small scale. This kind of heating occurs along a coast and in the mountains. Local winds blow over a small area and change direction and speed over a shorter period of time than global winds.

On a hot summer day at the beach, the land heats up faster than the water. The warmer air over land becomes less dense (low pressure) and rises; while the cooler denser (high pressure) air over the ocean rushes in to take its place. This wind is called a sea, or onshore, breeze.

After sunset, the land cools down faster than the water and becomes denser (high pressure). The warmer air, less dense (low pressure) over the ocean rises, while the cooler denser (high pressure) air over land rushes in to take its place. This wind is called a land, or offshore, breeze.

Global Winds: travel over long distances from a specific direction. Global winds are caused by the unequal heating of Earth’s surface. Air over the equator is heated at a direct angle from the Sun. This causes the air at the equator to heat up, become less dense and have lower pressure than the Polar Regions.

Global Convection Currents: At the equator, warm air becomes less dense (has lower pressure) due to heating and rises. At the poles, cold air is denser (has a higher pressure) and sinks. This causes huge convection currents. Winds at the surface tend to blow from the poles to the equator, while higher in the atmosphere; the winds tend to blow from the equator to the poles.

Global Wind Belts Doldrums: This is an area of little wind at the equator, because of warm temperatures.

Trade Winds: These winds travel from about 30o latitude to the equator.

Prevailing Westerlies: These winds travel from about 30o latitude to 60o latitude in the Northern and Southern Hemispheres. Prevailing westerlies play an important role in our weather.

Polar Easterlies: These winds travel from the poles to 60o latitude. The mixing of cold and warm air at this latitude has a big impact on our weather

The Coriolis effect The Coriolis effect Is a result of Earth’s rotation Causes moving objects to follow curved paths: In Northern Hemisphere, curvature is to right In Southern Hemisphere, curvature is to left Changes with latitude: No Coriolis effect at Equator Maximum Coriolis effect at poles

A merry-go-round as an example of the Coriolis effect To an observer above the merry-go-round, objects travel straight To an observer on the merry-go-round, objects follow curved paths Internet video of balls being rolled across a moving merry-go-round Figure 6-8

The Coriolis effect on Earth As Earth rotates, different latitudes travel at different speeds The change in speed with latitude causes the Coriolis effect Figure 6-9a

Missile paths demonstrate the Coriolis effect Two missiles are fired toward a target in the Northern Hemisphere Both missiles curve to the right Figure 6-9b

Ocean Currents An Ocean Current is a large volume of water flowing in a certain direction.

Surface Currents Wind-driven currents are called surface currents. Surface currents carry warm or cold water horizontally across the ocean’s surface. Surface currents extend to about 400 m below the surface, and they move as fast as 100 km/day.

Prevailing winds Earth’s major wind belts, called prevailing winds, influence the formation of ocean currents and the direction they move.

Density Currents: Density current is 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. Density currents circulate thermal energy, nutrients and gases.

Climates 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.

Examples The Gulf Stream is a warm-water current that affects coastal areas of the southeastern United States by transferring lots of thermal energy and moisture to the surrounding air. The greatest impact the Gulf Stream has on climate is found in Europe. It helps keep places like Ireland and England much warmer than they would otherwise be at such high latitude.

Examples The cold California Current affects coastal areas of the southwestern United States.

Waves A wave is a way in which energy travels from one place to another. There are many kinds of waves, such as water waves, sound waves, light waves, radio waves, microwaves and earthquake waves.

Waves The highest point the wave reaches is called the crest. The lowest point is called the trough. The distance from one crest to the next is the wave length. The number of waves that pass a given point in one second is the wave's frequency.

When wind blows over the ocean's surface, it creates waves When wind blows over the ocean's surface, it creates waves. Their size depends on how far, how fast and how long the wind blows. A brief, gentle breeze forms patches of tiny ripples on the surface; strong, steady winds over long distances create large waves. But even when you feel no wind at all, you may encounter large swells created by distant storms.

In the open sea, waves make floating boats bob up and down instead of pushing them along. This is because the waves travel through water; they do not take the water with them. As a wave arrives it lifts water particles. These travel forward, then down and back so that each particle completes a circle. Circling movements of particles near the surface set off smaller circling movements below them.

Fill in the LHA on Waves page 141 1. 5. 4. 3. 2.

1. Crest 2. Trough 5. Wave Height 4. Wave Length 3. Rest Position or Still water level 2. Trough