Layers of Atmosphere of the Earth

 

Layers of Atmosphere of the Earth

  • The atmosphere is composed of gases, water vapor, and dust particles.
  • Mixer of dust particles and water vapor is called aerosol.
  • It receives Incoming solar energy from the sun giving rise to climate.
  • We actually live at the bottom of this indefinite layer of the atmosphere.
  • One estimate puts this limit at about 600 miles (950 km) above sea level.
  • 99%  of the total mass of the atmosphere is confined to a height of 32 km from the earth’s surface.

 

Composition of Atmosphere of the Earth

 


Composition of Atmosphere of the Earth

  • The proportion of Gases changes in the higher layers of the atmosphere.
  • Oxygen will be almost in negligible quantity at the height of 120 km.
  • Similarly, carbon dioxide and water vapor are found only up to 90 km from the surface of the earth.

 

Water Vapor

  • It is constituting 2% to 4% of the total volume.
  • 90% of moisture content in the atmosphere exists within 6 km of the surface of the earth.
  • Water vapor plays a significant role in the insulating action, of the atmosphere.
  • It absorbs long-wave terrestrial radiation and part of the incoming solar radiation.
  • Water vapor is the source of precipitation and clouds.

 

Dust Particles

  • It consists of sand particles, pollen grains, small organisms, soot, and ocean salts.
  • These solid particles perform the function of absorbing, reflecting, and scattering radiation.
  • It is responsible for the orange and red colors at sunset and sunrise.
  • The blue color of the sky is due to selective scattering by dust particles.
  • Dust particles are an important factor in forming clouds, fog, and hailstones.

Layers of Atmosphere of the Earth

Layers of Atmosphere of the earth

 

Layers of Atmosphere of the Earth

  • The atmosphere consists of different layers with varying densities and temperatures.
  • Density is the highest near the surface of the earth and decreases with increasing altitude.
  • The column of the atmosphere is divided into 5 different layers depending upon the temperature condition.

 

Troposphere

  • The troposphere is the lowermost layer of the atmosphere.
  • Its average height is 13 km.
  • It extends roughly to a height of 8 km near the poles and about 18 km at the equator.
  • The thickness is greater at the equator because heat is transported to great heights by strong convectional currents.
  • The temperature in this layer, as one goes upwards, falls at the rate of 5°C / km
  • It reaches -45 °C at the poles and -80 °C at the equator.
  • The fall in temperature is called ‘lapse rate’.
  • The troposphere is marked by temperature inversion, turbulence, and eddies.
  • Almost all activities like rainfall, fog, and hailstorm, etc. happen in this layer.

 


Tropopause

  • It acts as a boundary between the troposphere and stratosphere.
  • This layer has a constant temperature.

Layers of Atmosphere of the Earth

Layers of Atmosphere

 

Stratosphere

  • The stratosphere extends up to an altitude of 50 km from the earth’s surface.
  • The temperature rises to reach a level of 0°C at 50 km altitude.
  • This rise is due to the presence of the ozonosphere.
  • The stratosphere layer is ideal for flying airplanes.
  • Sometimes, cirrus clouds are present at lower levels in this layer.

 

Ozonosphere

  • The ozonosphere lies at an altitude between 30 and 60 km from the earth’s surface.
  • It is a part of Stratosphere.
  • This layer absorbs ultraviolet radiation.
  • The ozonosphere is also called the chemosphere.

 

Mesosphere

  • This layer continues up to an altitude of 80 km from the earth’s surface.
  • The temperature gradually falls to -100°C at 80 km altitude.
  • Meteorites burn up in this layer on entering from space.

 

Thermosphere

  • In the thermosphere, the temperature rises very rapidly with increasing height.
  • The ionosphere is a part of this layer.
  • It’s an electrically charged layer.
  • It extends between 80-400 km.
  • The ionosphere helps in radio transmission.
  • The thermosphere is also known as the exosphere.
  • A person would not feel warm because of the thermosphere’s extremely low pressure.
  • The International Space Station and satellites orbit in this layer.
  • Auroras are observed in the lower parts of this layer.
  • Light gases like helium and hydrogen float into space from here.

 


en English

You cannot copy content of this page

Home
Explore
Prelim
Main
Mock Tests
Chat