LIFE ON EARTH

How is it possible?

ATOMOSPHERE

a thin layer of air that forms a protective

covering around the planet

Contains mixture of gases(O2 ), solids (dust,

pollen, salt), and liquids (water vapor)

circulated by winds

What would happen if there was no atmosphere?

Cold nights

Hot days

IMPORTANCE OF THE ATMOSPHERE

1-Balances the amount of heat absorbed and

the amount of heat escaping back to space

This heat comes from the Sun

2-Protects life forms from Sun’s harmful rays

How was it created?

Pictionary: Steps to develop atmosphere

MAKE-UP OF ATMOSPHERE

Time line:

Volcanoes producing water vapor, nitrogen, and

carbon dioxide

MAKE-UP OF THE ATMOSPHERE

Time line:

Volcanoes producing nitrogen and carbon

dioxide

Cyanobacteria living in ocean photosynthesized

to release oxygen into atmosphere

MAKE-UP OF THE ATMOSPHERE

Time line:

Volcanoes producing nitrogen and carbon

dioxide

Cyanobacteria living in ocean photosynthesized

to release oxygen into atmosphere

Ozone came about from oxygen in atmosphere

MAKE-UP OF THE ATMOSPHERE

Time line:

Volcanoes producing nitrogen and carbon

dioxide

Cyanobacteria living in ocean photosynthesized

to release oxygen into atmosphere

Ozone came about from oxygen in atmosphere

Plants were then protected from Sun and

produced oxygen for respirating organisms

MAKE-UP OF THE ATMOSPHERE

Time line:

Volcanoes producing nitrogen and carbon

dioxide

Cyanobacteria living in ocean photosynthesized

to release oxygen into atmosphere

Ozone came about from oxygen in atmosphere

Plants were then protected from Sun

GASES IN THE ATMOSPHERE

78% - Nitrogen (N)

21% - Oxygen (O2)

1% - trace gases

HOW WE CHANGE THE ATMOSPHERE

Car emissions adds CO2 to the atmosphere

Dangerous b/c CO2 is #1 greenhouse gas

Producing CFCs - chlorofluorocarbons

LAYERS OF THE ATMOSPHERE

characterized by abrupt temperature changes

Temp. changes due to difference in solar

energy absorption

LAYERS OF THE ATMOSPHERE

Troposphere

The inner most layer

Weather, clouds, we are here

Temperature decreases as you go up

Climbing a mountain

Tropopause

Boundary between the troposphere and the stratosphere

Temperature stabilizes

Limits mixing between the two layers

Stratosphere

Ozone layer – global sunscreen

absorbs energy from the sun heating the air

Aircraft flight in lower level

LAYERS OF THE ATMOSPHERE

Stratopause

Boundary between the stratosphere and

mesosphere

LAYERS OF THE ATMOSPHERE

Mesosphere

Meteoroids start to burn

Ionosphere exists here

Noctilucent clouds

LAYERS OF THE ATMOSPHERE

Mesopause

Boundary between mesosphere and thermosphere

Ionosphere – a layer of electrically charged particles located between the mesosphere and the thermosphere

It allows radio waves to travel across the country to other cities

Thermosphere

Auroras – reaction

between solar wind and

magnetic field where e-

are excited emitting

photons of light

International Space

Station

Exosphere

Region where atoms and molecules can escape

gravity and exit into space

Exosphere is the outer layer

of the atmosphere in which

the space shuttle flies.

Brain Pop Video on Atmosphere

OZONE

Ozone layer – a layer made of oxygen in the

stratosphere that absorbs most of the

ultraviolet radiation from the sun

3 types of suns rays – UVA, UVB, UVC sunglasses block A

and B ozone blocks C

Ultraviolet radiation – one type of energy that

comes to the Earth from the Sun

Causes skin damage and cancer

CFCs

Chlorofluorocarbons – an air pollutant that

destroys the ozone layer composed of Chlorine,

Fluorine, and carbon,

Used in some refrigerators, air conditioners (Freon),

aerosol cans (propellants), foam packaging

Good because non-flammable, odorless, cheap,

nontoxic, non-corrosive

Page 432

THE OZONE HOLE

Ultraviolet radiation breaks down CFCs causing

the depletion of ozone molecules leaving holes

in the ozone layer

THE OZONE HOLE

Sun breaks down CFC creating a free Chlorine atom

That chlorine atom breaks up O3 (ozone) when the

chlorine atom joins with 1 oxygen atom leaving 2

oxygen atoms together

The chlorine and oxygen molecule break up when

come in contact with another free oxygen atom and

the oxygen atoms hook-up

Now that free chlorine atom will find another ozone

molecule to break apart

SECTION 2

Energy Transfer in the Atmosphere

Air pressure

The weight of the

air/atmosphere above

you causes air pressure.

ATMOSPHERIC PRESSURE

ATMOSPHERIC PRESSURE

Air density (# of air

molecules in a given space)

is greatest at the surface

and decreases as you go up

Altitude and Air pressure

Air pressure decreases as altitude increases.

Altitude and Density

Measuring Air Pressure Tool used to measure air pressure is a

barometer.

Air pressure pushes down on the surface of the

mercury in the dish, causing the mercury in the

tube to rise. The air pressure is greater on the

barometer on the right, so the mercury is higher

in the tube.

ENERGY TRANSFER IN THE ATOMOSPHERE

What happens to the heat from the sun?

Absorbed by earth

Reflected by the earth’s surface

Absorbed by atmosphere

Reflected by atmosphere

ENERGY TRANSFER IN THE ATMOSPHERE

Heat flows from high temperatures to low

temperatures

Sun heats earth, earth heats atmosphere

Heat transfers through the atmosphere

in three ways: radiation, conduction,

and convection

RADIATION

energy transferred in the form of rays or waves.

Ex: holding your hand over a stove burner

CONDUCTION

the transfer of energy that occurs when

molecules bump into one another.

Ex: burner warming pot

CONVECTION

the transfer of heat by the flow of material.

Circulation of boiling water

RADIATION, CONDUCTION, OR CONVECTION?

Popping popcorn on the stove

Popping popcorn in electric popper

Microwave popcorn

What are the molecules doing?

Why does heat rise?

When air is warmed, the molecules move apart and

the air becomes less dense.

Air density decreases because there are fewer

molecules in one space.

What are the air molecules doing?

Why does cold air sink?

cold air molecules move close together becoming

more dense

https://www.youtube.com/watch?v=yUEPGMnRqGs

SO………

This creates convection currents which is how

heat is distributed throughout the atmosphere

HYDROLOGIC CYCLE

HYDROLOGIC (WATER) CYCLE

Hydrosphere – a term that describes all the

water on earth’s surface

Evaporation/transpiration – sun’s energy causes water

to change from a liquid to a gas

Precipitation – rain, sleet, snow, hail

Condensation – when the water vapor

cools it changes back into a liquid

SECTION 3

Air Movement

How is wind created?

Uneven heating of the Earth’s surface causes

winds

AIR MOVEMENT

Radiation from sun is received on Earth in different amounts because its curved

The equator gets more radiation than the poles because the rays are more direct

Warmer less dense air rises and the cooler air falls creating convection currents

Convection currents

CORIOLIS EFFECT

Coriolis effect – causes

moving air to turn left in

the S. Hemisphere and

turn right in the N.

Hemisphere due to

Earth’s rotation

Picture pg. 440, 441

Coriolis Effect Simulation

CONVECTION CURRENTS Trade winds – blow to the west as the cooled air flows

back to the equator between 0˚ and 30˚N and S

latitude

Called the trade winds because early sailors used the

patterns to navigate the oceans.

Westerlies – between 30˚N and S latitude and

60˚N and S latitude blow from the west

Polar Easterlies – between 60˚N and S latitude

to the N and S poles blow from the east away

from poles

WINDS IN THE UPPER TROPOSPHERE

Jet Stream – narrow

belts of strong winds

that blow near the

troposphere

LOCAL WIND SYSTEMS

Sea breezes- created during

the day because land is

warmed faster than water.

Land breezes – created

during the night because

water cools slower than land

LAND/SEA BREEZES