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

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 http://www.asc-csa.gc.ca/images/recherche/photo.aspx?id=967&format=0&search=earth&page=1

Layers of the Atmosphere The Exosphere Above 690 km Auroras occur here Outer Space The Thermosphere 85-690 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.

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. http://www.asc-csa.gc.ca/eng/educators/resources/scisat/grade6-atmosphere-what.asp

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

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.

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.

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).

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.

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 http://www1.fccj.cc.fl.us/pacrews/atmosphere1.htm

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

Biosphere Plants and animals vary gases in the atmosphere.