Sun’s Energy/Ocean Currents &

Wind

8.108.10

The student knows that climactic interactions exist The student knows that climactic interactions exist among Earth, ocean, and weather systems. The among Earth, ocean, and weather systems. The student is expected to:student is expected to:

(A) recognize that the Sun provides the energy that (A) recognize that the Sun provides the energy that drives convection within the atmosphere and the drives convection within the atmosphere and the oceans, producing winds and ocean currents.oceans, producing winds and ocean currents.

Radiant Energy

The SunThe Sun’’s energy is called radiant energy.s energy is called radiant energy.

The SunThe Sun’’s energy is responsible for the movement s energy is responsible for the movement of air in the atmosphere (wind) and the oceans of air in the atmosphere (wind) and the oceans (currents).(currents).

HOW? Through a process called CONVECTION.HOW? Through a process called CONVECTION.

Radiant Energy

Radiant energy drives CONVECTION within the Radiant energy drives CONVECTION within the atmosphere and the oceans.atmosphere and the oceans.

CONVECTION is the process of heat transfer in CONVECTION is the process of heat transfer in liquids (in the ocean) and air (in the atmosphere).liquids (in the ocean) and air (in the atmosphere).

Energy is transported and redistributed all over Energy is transported and redistributed all over the Earth. the Earth.

Exploring Convection Part 1Exploring Convection Part 1

Exploring Convection Part 2Exploring Convection Part 2

Convection Demos

Convection Everyday

Wind• Differences in density/air pressure cause Differences in density/air pressure cause

movement of air, which is wind.movement of air, which is wind.

• Winds are caused by the uneven heating of the Winds are caused by the uneven heating of the EarthEarth’’s surface (Equator vs. Poles)s surface (Equator vs. Poles)

• Warmer air is less dense (has less pressure) than Warmer air is less dense (has less pressure) than cooler air. cooler air.

• High pressure/more dense (cooler) air pushes low High pressure/more dense (cooler) air pushes low pressure/less dense (warm) air.pressure/less dense (warm) air.

• The greater the difference in pressure, the faster The greater the difference in pressure, the faster the wind blows.the wind blows.

• There are 2 types of winds: There are 2 types of winds: Global and LocalGlobal and Local

• Convection currents on a large Convection currents on a large scale produce global winds.scale produce global winds.

Types of Winds

Atmospheric Atmospheric

circulation circulation

and the and the

Coriolis Effect Coriolis Effect

create create

global wind global wind

patterns. patterns.

Global Winds

EarthEarth’’s curved surface s curved surface causes some parts of Earth causes some parts of Earth to receive the Sunto receive the Sun’’s rays s rays more directly than other more directly than other parts. parts.

As the warmer air over the As the warmer air over the equator rises, colder air equator rises, colder air from the poles rushes from the poles rushes toward the equator to take toward the equator to take its place. its place.

This steady exchange of This steady exchange of warm and cold air that warm and cold air that occurs between the occurs between the equator and the poles equator and the poles produces global wind belts. produces global wind belts.

Atmospheric Circulation

• The Earth rotates on its The Earth rotates on its axis, so circulating air is axis, so circulating air is deflected or turns. deflected or turns.

• This means that air This means that air

deflects in a clockwise deflects in a clockwise motion in the Northern motion in the Northern Hemisphere and Hemisphere and counterclockwise in the counterclockwise in the Southern Hemisphere, Southern Hemisphere, resulting in curved resulting in curved paths.paths.

• This deflection is known This deflection is known as the Coriolis Effect.as the Coriolis Effect.

The Coriolis Effect

Merry Go Round SimulationMerry Go Round Simulation

Coriolis Effect AnimationCoriolis Effect Animation

The Coriolis Effect: Click below!

Local Winds

Convection currents Convection currents on a small scale on a small scale produce local winds.produce local winds.

Local Winds•Small-scale convection currents cause local winds on the coast and in the mountains. •Blow over a much smaller area and change direction and speed over a shorter period of time than global winds.•There are 2 types of local winds: sea breezes and land breezes.

Sea Breeze (Daytime)

Sea Breeze

Land Breeze (Nighttime)

Land Breeze

How the Oceans Transport Energy

• The ocean transports energy from the The ocean transports energy from the Sun around the globe. HOW?Sun around the globe. HOW?

• To understand this, you have to learn To understand this, you have to learn more about ocean currents and wind.more about ocean currents and wind.

• There are 2 types of ocean currents: There are 2 types of ocean currents: surfacesurface currents and currents and deepdeep currents.currents.

Surface Ocean Currents• Surface ocean currents transport Surface ocean currents transport

thermal energy from the tropics thermal energy from the tropics (Equator) to the poles. (Equator) to the poles.

• Surface ocean currents are caused by Surface ocean currents are caused by winds. winds.

• The wind blows…it moves the water!!The wind blows…it moves the water!!

Deep Ocean Currents

• Deep ocean currents are caused by two Deep ocean currents are caused by two things: differences in things: differences in temperaturetemperature of of the water and the water and salinitysalinity of the water (how of the water (how salty it is).salty it is).

• These differences set convection in These differences set convection in motion, causing energy to be moved motion, causing energy to be moved deep within the ocean all over the deep within the ocean all over the globe.globe.

Density Currents

More dense water sinks and pushes up less dense More dense water sinks and pushes up less dense water. water.

This moves water around globe.This moves water around globe.