Earth's Atmosphere Composition and Layers

Composition

• The sky is made up of different layers of gases, including:
  • Nitrogen (78%)
  • Oxygen (21%)
  • Argon (1%)
  • Carbon dioxide (0.03%)
  • Water vapor (variable)
  • Other gases (trace amounts)

Atmospheric Layers

• The sky is divided into several atmospheric layers, including:
  1. Troposphere: extends up to 12 km, where weather occurs
  2. Stratosphere: extends from 12 km to 50 km, where ozone layer is located
  3. Mesosphere: extends from 50 km to 80 km, where meteors burn up
  4. Thermosphere: extends from 80 km to 600 km, where aurorae occur
  5. Exosphere: extends from 600 km to outer space, where atmospheric gases escape

Colors and Light

• The sky appears blue due to:
  • Scattering of sunlight by atmospheric gases (Rayleigh scattering)
  • Reflection of light by atmospheric particles (Mie scattering)
• During sunrise and sunset, the sky appears:
  • Reddish due to scattering of longer wavelengths of light
  • Orange and yellow due to scattering of intermediate wavelengths

Phenomena

• The sky is home to various natural phenomena, including:
  • Clouds: formed by condensation of water vapor
  • Rainbows: formed by refraction and dispersion of light through water droplets
  • Halos: formed by refraction of light through ice crystals
  • Aurorae: formed by interaction of solar winds with atmospheric gases
  • Meteor showers: formed by burning of meteoroids in the atmosphere

Composition

• The atmosphere is composed of 78% nitrogen, 21% oxygen, and 1% argon, with trace amounts of other gases.
• Carbon dioxide makes up a small percentage of the atmosphere, at approximately 0.03%.
• Water vapor is present in varying amounts, depending on atmospheric conditions.

Atmospheric Layers

• The troposphere is the lowest layer of the atmosphere, extending up to 12 km, where weather occurs.
• The stratosphere extends from 12 km to 50 km, and is home to the ozone layer.
• The mesosphere extends from 50 km to 80 km, and is where meteors burn up upon entry.
• The thermosphere extends from 80 km to 600 km, and is where aurorae occur.
• The exosphere is the outermost layer, extending from 600 km to outer space, where atmospheric gases escape.

Colors and Light

• The sky appears blue due to the scattering of sunlight by atmospheric gases, a process known as Rayleigh scattering.
• Mie scattering, or the reflection of light by atmospheric particles, also contributes to the blue color of the sky.
• During sunrise and sunset, the sky appears reddish due to the scattering of longer wavelengths of light.
• The scattering of intermediate wavelengths of light produces orange and yellow hues during these times.

Phenomena

• Clouds form when water vapor condenses in the atmosphere.
• Rainbows are created by the refraction and dispersion of light through water droplets.
• Halos are formed by the refraction of light through ice crystals.
• Aurorae occur when solar winds interact with atmospheric gases.
• Meteor showers occur when meteoroids burn up in the atmosphere, producing bright streaks of light.