1. Components of the Earth’s Climate System
Atmosphere
Hydrosphere
Lithosphere
Biosphere

2. The Atmosphere 600 km high Composition at Earth’s Surface:
78% Nitrogen
21% Oxygen
1% argon, carbon dioxide, helium, hydrogen, ozone
Some water vapour and dust
Traps solar Energy
Shields the planet from UV radiation

3. Layers of the Atmosphere
The Exosphere
Above 690 km
Auroras occur here
Outer Space
The Thermosphere km
Location of The Space Shuttle and International Space Station
Temperature rises as you go up
The Mesosphere
50-85 km
Meteors burn up = “shooting stars”
Temperature drops as low as -100oC as you go up.

4. Layers of the Atmosphere
The Stratosphere
20-50km
Location of the Ozone Layer – absorbs UV rays
CFC’s (chlorofuorocarbons)
React with ozone and deplete the ozone layer.
Formerly found in spray cans, refrigerators and air conditioners.
1987 -the Montreal Protocol banning the use of CFC’s was signed.
The ozone layer is recovering, will return to previous thickness in about 50 years
Location of airplanes and weather balloons
Temperature increases as you go up, to a maximum of 0oC.
The Troposphere
6-20km
Weather happens here
UV radiation + car exhaust produces ozone here = SMOG
Temperature decreases as you go up, to as low as -59oC.

5. The Hydrosphere Liquid water, water vapour, ice The Water Cycle
Evaporation from oceans, rivers, lakes
Energy is absorbed, COOLS the air
Condensation – formation of clouds
Energy is released, WARMS the air

6. On-Shore Breeze (daytime)
Some of the air travels out
Over the lake.
The lake cools the air.
Denser, cold air falls.
Convection current
The sun heats the land. Land has a low heat capacity and heats up fast. Land warms the air.
Warm air rises.
Air travels to the low
pressure area over the land.

7. Off-shore Breeze (night)
Some of the air moves
over the land. It cools and falls.
The lake stays warm
longer than land at
night. Warm lake water
warms the air above.
Warm air rises.
Air moves off-shore, to the low
pressure zone over the lake.

8. What’s the overall effect?
On-shore breezes cool the land on a warm day.
Off-shore breezes warm the air at night.
Overall effect: the climate next to a lake or river is more TEMPERATE than an inland area (temperate means cooler in summer and warmer in winter).

9. Ice and the Hydrosphere
Ice reflects solar rays, resulting in a cooler temperature than there normally would be.
Types of ice:
Sea Ice (pack ice)– in the Arctic
Land Ice (ice sheets) – in the Antarctic, Greenland
Glaciers – ice fields in mountains
Icebergs – broken sections of glaciers that are floating in the ocean.

10. The Lithosphere Earth’s Crust
Absorbs higher energy radiation, converts it to thermal energy, emits it back.
Orographic effect
Mountains – windward side is rainy and wet. Leeward side is dry

11. The Lithosphere and Altitude
High Altitude has less pressure – air from lower altitudes rises
As air rises, it expands and cools
Air is cooler at high altitudes

12. Biosphere
Plants and animals vary gases in the atmosphere.