Atmosphere Composition of the atmosphere

Document Sample
Atmosphere Composition of the atmosphere Powered By Docstoc
					                                                                                  Our atmosphere serves two
                                                                            1. Protects life on Earth from the Sun’s
   Atmosphere                                                                  harmful rays.
                                                                            2. Maintains a balance between amounts of
                                                                               heat absorbed from the sun and the
                                                                               amount of heat that escapes back into
           A layer of air that forms a
         protective covering around the

Composition of the atmosphere:                                                  The atmosphere is composed of:
                                                                            •   Solids- dust, pollen, salt
                                                                            •   Liquids- water etc.
                                                                            •   Gases-
                                                                            •    Nitrogen (78%) produced from
                                                                                – volcanic eruptions,
                                                                                – dead and decaying plants.
                                                                            • Oxygen (21%)
                                                                                – produced by plants (photosynthesis)

   Atmosphere is composed of 5 layers.
   These layers are based on pressure and temperature,
   which are affected by altitude.


Air Pressure                                        Temperature

-as altitude increases,                           - as altitude increases
 air pressure decreases                            temperature changes
                          Which are effected by


              As altitude increases,            As altitude changes, so does the
              air pressure decreases.                     temperature.

 Both air pressure and temperature             • Troposphere: 0 – 16
    are affected by the altitude               • Tropo=turning or
• As altitude increases, pressure decreases.
  The molecules at the bottom layer            • Weather takes place
  (Troposphere) have more pressure on
  them to force them together than those at    • 90% of the
                                                 atmosphere’s total
  the top layer (Thermosphere).                  mass
• Temperature differences result from the           0°c
                                               • - 6 at the top of the
  way solar energy is absorbed as it moves       troposphere
  down through the layers of the               • As altitude increases,
  atmosphere.                                    temperature

                                               • Mesosphere: 50 – 80 km
• Stratosphere: 16 – 50 km
                                               • Meso = middle
• Strato= layer or spreading out               • Temperature decreases
• Jet stream = contains broad,
                                                 as altitude increases.
  fast flowing “rivers of air” called          • Outer mesosphere is the
  jet streams. These jet streams                 coldest part of the
  can change weather patterns                    atmosphere. -93°c at the
  in the troposphere.                            top.
• Upper layer is warmer than                   • Protects Earth’s surface.
  lower due to ozone layer.                      This is where meteoroids
• Ozone layer= O3 (Ozone)                        burn up upon entry into
  absorbs sun’s ultraviolet rays,                the atmosphere:
  so temperature increases. IT                   “shooting stars”.
  is very thin, only 2.5-3.5 mm                • Scientists have recently
  thick. O2 (Oxygen) vs O3
                                                 discovered large
                                                 windstorms with winds
• -60°c to 0°c                                   speeds up to 320 km/h in
                                                 this layer.

                                • Ionosphere:
• Thermosphere: 80 – 550        • Lower layer of the
  km                              thermosphere composed
                                  primarily of oxygen.
• Thermo = heat
                                • Absorbs x-rays and gamma
• Largest layer, .001             rays, which contribute to the
  percent as dense as the         high temperature and cause
                                  the gas molecules to become
  air at sea level.               electronically charged (ions).
• Temperature increases         • Aurora Borealis/Australis: The
  as altitude increases.          northern and southern lights.
                                  Particles from the sun enter
  Temperatures reach              and strike oxygen and nitrogen
  1700°c.                         particles, causing them to
• Very hot because energy
                                • The ionosphere can reflect
  coming from the sun             many types of radio waves,
  strikes this layer first.       allowing them to bounce
                                  around the world.
• Energy = heat

• Exosphere: Above 550
  km                                          5 Layers Revisited
• No true end of
  atmosphere. Gas
  molecules simply break
  free of Earth’s gravity and
• Space shuttles, ISS
  (International Space
  Station) and satellites
  orbit the earth in this
  layer. This is how long
  distance calls, satellite
  TV, internet, cell phones,
  etc., reach you.