The Air Around You

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The Air Around You

• Chapter 1- Atmosphere

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Section1- Earths Atmosphere

• Importance
• Thin layer of air that forms a protective layer
  around the Earth
• Without it, extremely warm days and cold nights
• Allows a balance of heat from the sun to be
  absorbed and given off
• Protection from harmful rays

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Make-up of Atmosphere

• Mix of gases, solids, and liquids
• Gases
• 78 Nitrogen N
• 21 Oxygen O
• Up to 4 Water Vapor
• Rest Argon, Carbon Dioxide, Neon, Hydrogen,
  Helium, Ozone, etc
• Liquids and solids
• Dust, salt, pollen
• Liquid droplets

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Atmosphere Layers

• 5 layers
• Lowest- Troposphere
• Closest to Earth, where we live
• Has 99 of atmosphere water vapor and 75 of the
  gases
• Up to 10 km
• Next- Stratosphere
• 10km-50km up
• Portion contains ozone O3

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Upper Layers

• Mesosphere
• Top of stratosphere at 50km to 85km
• Thermosphere
• High temperatures
• 85km-500km
• Within thermosphere have ionosphere that is a
  layer of charged particles- carries radio waves
• Exosphere
• Outermost layer
• Space shuttle orbits here
• Few molecules

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Atmospheric Pressure

• Pressure is force exerted upon an area
• Decreases as you go up
• Gravity pulls gases to surface, more at surface
  then higher up (more dense)

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Temperature in Layers

• Suns energy passes through
• Troposphere- warmer at lower elevation due to
  Earths warmth
• Stratosphere- Ozone traps heat so it increases as
  you go up
• Mesosphere- cooler as you go up
• Thermosphere and Exosphere higher temperature as
  increase altitude

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Ozone Layer

• O3 3 oxygen attached together
• Shields us from suns harmful UV (Ultraviolet)
  rays
• CFCs- chlorofluorocarbons- air pollutants from
  aerosol cans, air conditioners, refrigerators
  that have made hole in ozone
• Increase in UV rays- skin cancer

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Section 2- Energy Transfer in Atmosphere

• Heat- reaches surface and heats objects
• Radiation- transfer in form of waves or rays
• Conduction- transfer when molecules bump into
  each other- warmer to cooler
• Convection- transfer by flow of material
• Cooler air denser, sinks

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Water Cycle

• Hydrosphere- all water on Earths Surface
• Water moves between hydrosphere and atmosphere
• Condensation- vapor to droplets
• Evaporation- liquid to vapor
• Precipitation- water from clouds-rain,snow,sleet

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Section 3- Air Movement

• Coriolis Effect- rotation of Earth causes air and
  water to appear to turn right North of Equator
  and left South of it

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Winds

• Trade winds- steady winds in tropical regions-
  0-300 latitude-good for sailors
• Prevailing Westerlies- 30-60o latitude- opposite
  from trade winds, movement of weather across
  North America
• Prevailing Easterlies- near poles- NE?SW at North
  Pole, SE?NW in South
• Doldrums- no wind at
• equator

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Winds in Troposphere

• Jet Stream- narrow belts of strong winds
• Used by jet pilots

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Sea Breeze

• Convection currents over areas where land meets
  sea
• Sea breeze-Created during day when solar
  radiation warms sand more than water
• By conduction
• Less dense and lower
• pressure
• Cooler denser air over
• water has higher
• pressure and flows
• toward land

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Land Breeze

• Opposite
• At night, land cools faster than water
• Become more dense, pushes warmer, denser air over
  ocean
• Breeze from land to water

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Clouds Assignment p.128-133
Date________________
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And that is the end