CLIMATE CHANGE!

DroughtsWind speedTropical zoneAir pressureSunshineTornado

WEATHER or CLIMATE?Can you tell the difference?

Put these words in to two lists under the headings ‘Weather words’ and ‘Climate words’

Cold wintersCloud coverWet summersTemperatureWind directiondewpoint

CW

CW

WW

C

W

C

W

W

W

Weather vs. Climate? (8.1)

What is weather?› Atmospheric conditions in a

particular location over a short period of time

What is climate?› The average weather in a region

over a long period of time› The Earth’s climate has

changed dramatically over the Earth’s history

Who is Affected by Weather and Climate?

EVERYONE!!

Climate (8.2)

Climate Zone: areas on Earth with similar climates

What are some areas on Earth that have similar climate?

What factors influence climate?

Can you think of some factors that cause different climates in different areas???

Climate is caused by:› 1. Latitude (distance from the equator)› 2. the presence of large bodies of water› 3. The presence of ocean or air currents› 4. Land formations› 5. Altitude (height above see level)

Earth’s Climate System

Climate System: the complex set of components that interact with each other to produce Earth’s climate

What do you think these components are?› Air, Land, Liquid Water, Ice, Living things

What powers this system? The Sun!

The interaction of these components and the sun produce climate zones!

The Sun! (8.3)

Almost all energy on Earth comes from the sun, in the form of UV radiation, visible light and infrared radiation 30% of sun’s energy is reflected 70% of it is absorbed (by surface,

clouds or atmosphere)

The Sun’s Energy If Earth’s absorbs 70% of the sun’s energy how

come it isn’t just getting hotter and hotter?? The sun’s energy can be converted from one

form to another Earth absorbs different wavelengths from the

sun, heats up and gains thermal energy It then emits this as infrared radiation which

returns to the atmosphere and back into space

energy absorbed = energy radiated

so Earth’s global temperature stays constant

Latitude and Climate Zones How does latitude affect Climate? Climate is warmer closer to the equator Why?

› More direct sunlight (less spread out)› Less atmosphere to pass through (because

less spread out)

The Atmosphere (8.4)

Atmosphere: the layers of gases surrounding the earth

78% nitrogen 21% oxygen 1% argon, CO2, helium, hydrogen, ozone Reflects, absorbs and radiates, or transmits

energy Acts as a blanket – conserving thermal

energy to keep Earth warm Also shields earth from dangerous radiation

Ozone (O3) in the stratosphere

In the stratosphere (50km up), ozone absorbs dangerous UV radiation protects us!

Human made chlorofluorocarbons (CFCs) thins the ozone (less protection!)

CFCs were in spray cans, refrigerators and AC and were banned in 1987

The ozone has slowly been recovering

Ozone in the Troposphere

Ozone in the troposphere (6-20km) is toxic and corrosive

Created from car exhausts reacting in UV radiation

Produces smog – harmful to human health, damages buildings and affects plans and animals

Drive clean introduced to help reduce it

Hydrosphere

Liquid water, water vapour and ice Reflect, absorb and emit, or tramsits

energy from the sun Water Cycle

› Energy is absorbed when water evaporates cools surroundings

› Energy is given off when water vapour condenses into clouds warms surroundings

Large Bodies of water

How do these affect climate? Water absorbs and stores more thermal

energy than land Water heats up and cools down more

slowly than land Regions near oceans or a large lake are

cooler during the summer and warmer during the winter

Regions downwind from large bodies of water have more snow

Ice

How does Ice Affect Climate? 2% of Earth’s water is frozen Most ice is located at the two poles Sea ice: thin and floats on the ocean Ice sheets: enormous areas of

permanent ice stretching over land Surfaces covered in ice and snow reflect

more radiant energy than land (another reason why the poles are so cold)

Litosphere Litosphere: Earth’s Crust Absorbs high energy radiation from the

sun, converts it to thermal energy, and emits it as low energy infrared radiation

How do you think mountains affect climate? › Clouds lose moisture as rain on one side of

the mountain and the other side is dry!

Litosphere What about the climate on at higher

altitudes?› Higher up there’s less pressure which

causes air to expand and cool so it’s cold!

Living Things Organisms change the amount of gas in the

atmosphere through photosynthesis and cellular respiration

Some animals (cows, sheep, termites and bacteria) produce methane gas

Carbon dioxide and methane absorb infrared radiation

A change in the amount of these gases affects how much radiation is absorbed

https://www.youtube.com/watch?v=lrPS2HiYVp8

https://www.youtube.com/watch?v=ZouWWVyz9v8

HOMEWORK!

Read pg.319-335 Questions: Pg. 321 #1, 4, 5 Pg. 329 # 1-6 Pg. 335 #1, 3-5