The Atmosphere

For the man sound in body and serene of mind there is no such thing as bad weather; every sky has its beauty, and storms which whip the blood do but make it pulse more vigorously.

George Gissing

• Definition: The layer of gases surrounding Earth; the blanket of air around the Earth
• Composed mainly of nitrogen and oxygen
• Divided into layers based on temperature
• Troposphere
• Layer closest to the surface of the Earth
• T decreases as altitude increases (it gets colder the higher you go)
• Where weather occurs
  • Boundary between troposphere & stratosphere is tropopause
• Stratosphere
• T increases as altitude increases (it gets warmer the higher you go)
• Airplanes travel here
• Contains the ozone layer
• Protects us from ultraviolet radiation by absorbing it before it reaches the surface
• Prevents heat loss
• Boundary between stratosphere and mesosphere is stratospause
• Mesosphere
• T decreases with altitude
• Boundary between mesosphere and thermosphere is mesopause
• Thermosphere
• T increases with altitude
• Contains ionosphere
• Where Northern (and Southern) Lights occur
• Boundary between thermosphere and exosphere is thermopause
• Exosphere
• Gases can escape into outer space