Which among the following is the coldest of the atmospheric layers? 

The correct answer is Mesosphere.

Key Points

• Mesosphere
  • It lies above the stratosphere, which extends up to a height of 80 km.
  • In this layer, once again, the temperature starts decreasing with the increase in altitude and reaches up to minus 100°C at a height of 80 km.
  • The upper limit of the mesosphere is known as mesopause​

Additional Information

• Stratosphere
  • It is found above the tropopause and extends up to a height of 50 km.
  • One important feature of the stratosphere is that it contains the ozone layer.
  • This layer absorbs ultra-violet radiation and shields life on the earth from an intense, harmful form of energy.
  • The stratopause caps the top of the stratosphere.
• Thermosphere ​
  • It is located between 80 and 400 km above the mesopause.
  • It contains electrically charged particles known as ions, and hence, it is also known as the ionosphere.
  • Radio waves transmitted from the earth are reflected back to the earth by this layer.
  • The temperature here starts increasing with height.
• Troposphere
  • Its average height is 13 km.
  • Troposphere is the densest layer of all.
  • The air we breathe exists here.
  • Almost all the weather phenomena like rainfall, fog, and hailstorm occur in this layer.